diff --git a/README.md b/README.md
index 867c66e7..5a9cf91f 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,7 @@ At the moment, it provides the groups:
   introduced (to the best of knowledge) in this [paper][barrau15].
   NOTE: The implementation here differs slightly from
   the developments in the [paper][barrau15].
+- SGal(3): The Special Galilean group (rotation, translation, velocity and time) in 3D space, described in these papers [[1][fourmy19]] & [[2][kelly24]].
 - Bundle<>: allows manipulating a manifold bundle as a single Lie group.
   Referred to as a *composite manifold* in Section IV of the
   [reference paper](http://arxiv.org/abs/1812.01537).
@@ -170,6 +171,8 @@ Want to contribute? Great! Check out our [contribution guidelines](CONTRIBUTING.
 [jsola18]: http://arxiv.org/abs/1812.01537
 [jsola18v]: http://arxiv.org/abs/1812.01537v4
 [barrau15]: https://arxiv.org/pdf/1410.1465.pdf
+[fourmy19]: https://hal.science/hal-02183498/document
+[kelly24]: https://arxiv.org/abs/2312.07555
 [deray20]: https://joss.theoj.org/papers/10.21105/joss.01371
 
 [jsola-iri-lecture]: https://www.youtube.com/watch?v=nHOcoIyJj2o
diff --git a/include/manif/SGal3.h b/include/manif/SGal3.h
new file mode 100644
index 00000000..895e29ea
--- /dev/null
+++ b/include/manif/SGal3.h
@@ -0,0 +1,16 @@
+#ifndef _MANIF_SGAL3_H_
+#define _MANIF_SGAL3_H_
+
+#include "manif/impl/macro.h"
+#include "manif/impl/lie_group_base.h"
+#include "manif/impl/tangent_base.h"
+
+#include "manif/impl/sgal3/SGal3_properties.h"
+#include "manif/impl/sgal3/SGal3_base.h"
+#include "manif/impl/sgal3/SGal3Tangent_base.h"
+#include "manif/impl/sgal3/SGal3.h"
+#include "manif/impl/sgal3/SGal3Tangent.h"
+#include "manif/impl/sgal3/SGal3_map.h"
+#include "manif/impl/sgal3/SGal3Tangent_map.h"
+
+#endif // _MANIF_SGAL3_H_
diff --git a/include/manif/impl/sgal3/SGal3.h b/include/manif/impl/sgal3/SGal3.h
new file mode 100644
index 00000000..66312d08
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3.h
@@ -0,0 +1,254 @@
+#ifndef _MANIF_MANIF_SGAL3_H_
+#define _MANIF_MANIF_SGAL3_H_
+
+#include "manif/impl/sgal3/SGal3_base.h"
+
+namespace manif {
+
+// Forward declare for type traits specialization
+template <typename _Scalar> struct SGal3;
+template <typename _Scalar> struct SGal3Tangent;
+
+namespace internal {
+
+//! Traits specialization
+template <typename _Scalar>
+struct traits<SGal3<_Scalar>> {
+  using Scalar = _Scalar;
+
+  using LieGroup = SGal3<_Scalar>;
+  using Tangent  = SGal3Tangent<_Scalar>;
+
+  using Base = SGal3Base<SGal3<_Scalar>>;
+
+  static constexpr int Dim = LieGroupProperties<Base>::Dim;
+  static constexpr int DoF = LieGroupProperties<Base>::DoF;
+  static constexpr int RepSize = 11;
+
+  /// @todo would be nice to concat vec3 + quaternion + vec3 + t
+  using DataType = Eigen::Matrix<Scalar, RepSize, 1>;
+
+  using Jacobian       = Eigen::Matrix<Scalar, DoF, DoF>;
+  using Rotation       = Eigen::Matrix<Scalar, 3, 3>;
+  using Translation    = Eigen::Matrix<Scalar, 3, 1>;
+  using LinearVelocity = Eigen::Matrix<Scalar, 3, 1>;
+  using Vector         = Eigen::Matrix<Scalar, 3, 1>;
+};
+
+} // namespace internal
+} // namespace manif
+
+namespace manif {
+
+//
+// LieGroup
+//
+
+/**
+ * @brief Represent an element of SGal3.
+ */
+template <typename _Scalar>
+struct SGal3 : SGal3Base<SGal3<_Scalar>> {
+private:
+
+  using Base = SGal3Base<SGal3<_Scalar>>;
+  using Type = SGal3<_Scalar>;
+
+protected:
+
+  using Base::derived;
+
+public:
+
+  MANIF_MAKE_ALIGNED_OPERATOR_NEW_COND
+
+  MANIF_COMPLETE_GROUP_TYPEDEF
+  using Translation = typename Base::Translation;
+  using Quaternion  = Eigen::Quaternion<Scalar>;
+  using LinearVelocity = typename Base::LinearVelocity;
+
+  MANIF_INHERIT_GROUP_API
+  using Base::rotation;
+  using Base::normalize;
+
+  SGal3()  = default;
+  ~SGal3() = default;
+
+  MANIF_COPY_CONSTRUCTOR(SGal3)
+  MANIF_MOVE_CONSTRUCTOR(SGal3)
+
+  template <typename _DerivedOther>
+  SGal3(const LieGroupBase<_DerivedOther>& o);
+
+  MANIF_GROUP_ASSIGN_OP(SGal3)
+
+  /**
+   * @brief Constructor given a translation, a unit quaternion and a linear velocity.
+   * @param[in] t A translation vector.
+   * @param[in] q A unit quaternion.
+   * @param[in] v A linear velocity vector.
+   * @param[in] time A time.
+   * @throws manif::invalid_argument on un-normalized complex number.
+   */
+  SGal3(
+    const Translation& t,
+    const Eigen::Quaternion<Scalar>& q,
+    const LinearVelocity& v,
+    const Scalar time
+  );
+
+  /**
+   * @brief Constructor given a translation, an angle axis and a linear velocity.
+   * @param[in] t A translation vector.
+   * @param[in] angle_axis An angle-axis.
+   * @param[in] v A linear velocity vector.
+   * @param[in] time A time.
+   */
+  SGal3(
+    const Translation& t,
+    const Eigen::AngleAxis<Scalar>& angle_axis,
+    const LinearVelocity& v,
+    const Scalar time
+  );
+
+  /**
+   * @brief Constructor given a translation, SO3 element and a linear velocity.
+   * @param[in] t A translation vector.
+   * @param[in] SO3 An element of SO3.
+   * @param[in] v A linear velocity vector.
+   * @param[in] time A time.
+   */
+  SGal3(
+    const Translation& t,
+    const SO3<Scalar>& SO3,
+    const LinearVelocity& v,
+    const Scalar time
+  );
+
+  /**
+   * @brief Constructor given translation components,
+   * roll-pitch-yaw angles and linear velocity components
+   * @param[in] x The x component of the translation.
+   * @param[in] y The y component of the translation.
+   * @param[in] z The z component of the translation.
+   * @param[in] roll The roll angle.
+   * @param[in] pitch The pitch angle.
+   * @param[in] yaw The yaw angle.
+   * @param[in] vx The x component of the linear velocity.
+   * @param[in] vy The y component of the linear velocity.
+   * @param[in] vz The z component of the linear velocity.
+   * @param[in] t time.
+   */
+  SGal3(
+    const Scalar x, const Scalar y, const Scalar z,
+    const Scalar roll, const Scalar pitch, const Scalar yaw,
+    const Scalar vx, const Scalar vy, const Scalar vz,
+    const Scalar t
+  );
+
+  /**
+   * @brief Constructor from a 3D Eigen::Isometry<Scalar> relevant to SE(3) and a linear velocity
+   * @param[in] h a isometry object from Eigen defined for SE(3)
+   * @param[in] v a linear velocity vector.
+   * @note overall, this should be a double direct spatial isometry,
+   */
+  SGal3(
+    const Eigen::Transform<_Scalar,3,Eigen::Isometry>& h,
+    const LinearVelocity& v,
+    const Scalar t
+  );
+
+  // LieGroup common API
+
+  DataType& coeffs();
+  const DataType& coeffs() const;
+
+  // SGal3 specific API
+
+protected:
+
+  DataType data_;
+};
+
+MANIF_EXTRA_GROUP_TYPEDEF(SGal3)
+
+template <typename _Scalar>
+template <typename _DerivedOther>
+SGal3<_Scalar>::SGal3(const LieGroupBase<_DerivedOther>& o) : SGal3(o.coeffs()) {
+  //
+}
+
+template <typename _Scalar>
+SGal3<_Scalar>::SGal3(
+  const Translation& t,
+  const Eigen::Quaternion<Scalar>& q,
+  const LinearVelocity& v,
+  const Scalar time
+) : SGal3((DataType() << t, q.coeffs(), v, time).finished()) {
+  //
+}
+
+template <typename _Scalar>
+SGal3<_Scalar>::SGal3(
+  const Translation& t,
+  const Eigen::AngleAxis<Scalar>& a,
+  const LinearVelocity& v,
+  const Scalar time
+) : SGal3(t, Quaternion(a), v, time) {
+  //
+}
+
+template <typename _Scalar>
+SGal3<_Scalar>::SGal3(
+  const Scalar x, const Scalar y, const Scalar z,
+  const Scalar roll, const Scalar pitch, const Scalar yaw,
+  const Scalar vx, const Scalar vy, const Scalar vz,
+  const Scalar t
+) : SGal3(
+  Translation(x,y,z),
+  Eigen::Quaternion<Scalar>(
+    Eigen::AngleAxis<Scalar>(yaw,   Eigen::Matrix<Scalar, 3, 1>::UnitZ()) *
+    Eigen::AngleAxis<Scalar>(pitch, Eigen::Matrix<Scalar, 3, 1>::UnitY()) *
+    Eigen::AngleAxis<Scalar>(roll,  Eigen::Matrix<Scalar, 3, 1>::UnitX())
+  ),
+  LinearVelocity(vx, vy, vz),
+  t
+) {
+  //
+}
+
+template <typename _Scalar>
+SGal3<_Scalar>::SGal3(
+  const Translation& t,
+  const SO3<Scalar>& so3,
+  const LinearVelocity& v,
+  const Scalar time
+) : SGal3(t, so3.quat(), v, time) {
+  //
+}
+
+template <typename _Scalar>
+SGal3<_Scalar>::SGal3(
+  const Eigen::Transform<_Scalar, 3, Eigen::Isometry>& h,
+  const LinearVelocity& v,
+  const Scalar t
+) : SGal3(h.translation(), Eigen::Quaternion<_Scalar>(h.rotation()), v, t) {
+  //
+}
+
+
+template <typename _Scalar>
+typename SGal3<_Scalar>::DataType&
+SGal3<_Scalar>::coeffs() {
+  return data_;
+}
+
+template <typename _Scalar>
+const typename SGal3<_Scalar>::DataType&
+SGal3<_Scalar>::coeffs() const {
+  return data_;
+}
+
+} // namespace manif
+
+#endif // _MANIF_MANIF_SGAL3_H_
diff --git a/include/manif/impl/sgal3/SGal3Tangent.h b/include/manif/impl/sgal3/SGal3Tangent.h
new file mode 100644
index 00000000..97692f18
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3Tangent.h
@@ -0,0 +1,106 @@
+#ifndef _MANIF_MANIF_SGAL3TANGENT_H_
+#define _MANIF_MANIF_SGAL3TANGENT_H_
+
+#include "manif/impl/sgal3/SGal3Tangent_base.h"
+
+namespace manif {
+namespace internal {
+
+//! Traits specialization
+template <typename _Scalar>
+struct traits<SGal3Tangent<_Scalar>> {
+  using Scalar = _Scalar;
+
+  using LieGroup = SGal3<_Scalar>;
+  using Tangent  = SGal3Tangent<_Scalar>;
+
+  using Base = SGal3TangentBase<Tangent>;
+
+  static constexpr int Dim     = LieGroupProperties<Base>::Dim;
+  static constexpr int DoF     = LieGroupProperties<Base>::DoF;
+  static constexpr int RepSize = DoF;
+
+  using DataType = Eigen::Matrix<Scalar, RepSize, 1>;
+
+  using Jacobian = Eigen::Matrix<Scalar, DoF, DoF>;
+  using LieAlg   = Eigen::Matrix<Scalar, 5, 5>;
+};
+
+} // namespace internal
+} // namespace manif
+
+namespace manif {
+
+//
+// Tangent
+//
+
+/**
+ * @brief Represents an element of tangent space of SGal3.
+ */
+template <typename _Scalar>
+struct SGal3Tangent : SGal3TangentBase<SGal3Tangent<_Scalar>> {
+private:
+
+  using Base = SGal3TangentBase<SGal3Tangent<_Scalar>>;
+  using Type = SGal3Tangent<_Scalar>;
+
+protected:
+
+    using Base::derived;
+
+public:
+
+  MANIF_MAKE_ALIGNED_OPERATOR_NEW_COND
+
+  MANIF_TANGENT_TYPEDEF
+  MANIF_INHERIT_TANGENT_API
+  MANIF_INHERIT_TANGENT_OPERATOR
+
+  SGal3Tangent()  = default;
+  ~SGal3Tangent() = default;
+
+  MANIF_COPY_CONSTRUCTOR(SGal3Tangent)
+  MANIF_MOVE_CONSTRUCTOR(SGal3Tangent)
+
+  template <typename _DerivedOther>
+  SGal3Tangent(const TangentBase<_DerivedOther>& o);
+
+  MANIF_TANGENT_ASSIGN_OP(SGal3Tangent)
+
+  // Tangent common API
+
+  DataType& coeffs();
+  const DataType& coeffs() const;
+
+  // SGal3Tangent specific API
+
+protected:
+
+  DataType data_;
+};
+
+MANIF_EXTRA_TANGENT_TYPEDEF(SGal3Tangent);
+
+template <typename _Scalar>
+template <typename _DerivedOther>
+SGal3Tangent<_Scalar>::SGal3Tangent(const TangentBase<_DerivedOther>& o)
+  : data_(o.coeffs()) {
+  //
+}
+
+template <typename _Scalar>
+typename SGal3Tangent<_Scalar>::DataType&
+SGal3Tangent<_Scalar>::coeffs() {
+  return data_;
+}
+
+template <typename _Scalar>
+const typename SGal3Tangent<_Scalar>::DataType&
+SGal3Tangent<_Scalar>::coeffs() const {
+  return data_;
+}
+
+} // namespace manif
+
+#endif // _MANIF_MANIF_SGAL3TANGENT_H_
diff --git a/include/manif/impl/sgal3/SGal3Tangent_base.h b/include/manif/impl/sgal3/SGal3Tangent_base.h
new file mode 100644
index 00000000..ad705827
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3Tangent_base.h
@@ -0,0 +1,623 @@
+#ifndef _MANIF_MANIF_SGAL3TANGENT_BASE_H_
+#define _MANIF_MANIF_SGAL3TANGENT_BASE_H_
+
+#include "manif/impl/sgal3/SGal3_properties.h"
+#include "manif/impl/tangent_base.h"
+#include "manif/impl/so3/SO3Tangent_map.h"
+#include "manif/impl/se3/SE3Tangent.h"
+
+namespace manif {
+
+//
+// Tangent
+//
+
+/**
+ * @brief The base class of the SGal3 tangent.
+ */
+template <typename _Derived>
+struct SGal3TangentBase : TangentBase<_Derived> {
+private:
+
+  using Base = TangentBase<_Derived>;
+  using Type = SGal3TangentBase<_Derived>;
+
+public:
+
+  MANIF_TANGENT_TYPEDEF
+  MANIF_INHERIT_TANGENT_API
+  MANIF_INHERIT_TANGENT_OPERATOR
+
+  using LinBlock = typename DataType::template FixedSegmentReturnType<3>::Type;
+  using AngBlock = typename DataType::template FixedSegmentReturnType<3>::Type;
+  using ConstLinBlock = typename DataType::template ConstFixedSegmentReturnType<3>::Type;
+  using ConstAngBlock = typename DataType::template ConstFixedSegmentReturnType<3>::Type;
+
+  using Base::data;
+  using Base::coeffs;
+
+protected:
+
+  using Base::derived;
+
+  MANIF_DEFAULT_CONSTRUCTOR(SGal3TangentBase)
+
+public:
+
+  MANIF_TANGENT_ML_ASSIGN_OP(SGal3TangentBase)
+
+  // Tangent common API
+
+  /**
+   * @brief Hat operator of SGal3.
+   * @return An element of the Lie algebra se_2_3.
+   * @note See Eq. (169).
+   */
+  LieAlg hat() const;
+
+  /**
+   * @brief Get the SGal3 element.
+   * @param[out] -optional- J_m_t Jacobian of the SGal3 element wrt this.
+   * @return The SGal3 element.
+   * @note This is the exp() map with the argument in vector form.
+   */
+  LieGroup exp(OptJacobianRef J_m_t = {}) const;
+
+  /**
+   * @brief This function is deprecated.
+   * Please considere using
+   * @ref exp instead.
+   */
+  MANIF_DEPRECATED
+  LieGroup retract(OptJacobianRef J_m_t = {}) const;
+
+  /**
+   * @brief Get the right Jacobian of SGal3.
+   */
+  Jacobian rjac() const;
+
+  /**
+   * @brief Get the left Jacobian of SGal3.
+   */
+  Jacobian ljac() const;
+
+  /**
+   * @brief Get the small adjoint matrix ad() of SGal3
+   * that maps isomorphic tangent vectors of SGal3
+   * @return
+   */
+  Jacobian smallAdj() const;
+
+  // SGal3Tangent specific API
+
+  //! @brief Get the linear translation part.
+  LinBlock lin();
+  const ConstLinBlock lin() const;
+
+  //! @brief Get the angular part.
+  AngBlock ang();
+  const ConstAngBlock ang() const;
+
+  //! @brief Get the linear velocity part
+  LinBlock lin2();
+  const ConstLinBlock lin2() const;
+
+  Scalar t() const;
+
+public: /// @todo make protected
+
+  const Eigen::Map<const SO3Tangent<Scalar>> asSO3() const {
+    return Eigen::Map<const SO3Tangent<Scalar>>(coeffs().data()+6);
+  }
+
+  Eigen::Map<SO3Tangent<Scalar>> asSO3() {
+    return Eigen::Map<SO3Tangent<Scalar>>(coeffs().data()+6);
+  }
+
+  static void fillE(
+    Eigen::Ref<Eigen::Matrix<Scalar, 3, 3>> E,
+    const Eigen::Map<const SO3Tangent<Scalar>>& so3
+  );
+};
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::LieGroup
+SGal3TangentBase<_Derived>::exp(OptJacobianRef J_m_t) const {
+  if (J_m_t) {
+    *J_m_t = rjac();
+  }
+
+  const Eigen::Map<const SO3Tangent<Scalar>> so3 = asSO3();
+  const typename SO3<Scalar>::Jacobian so3_ljac = so3.ljac();
+
+  Eigen::Matrix<Scalar, 3, 3> E;
+  fillE(E, so3);
+
+  return LieGroup(
+    so3_ljac * lin() + (E * (t() * lin2())),
+    so3.exp(),
+    so3_ljac * lin2(),
+    t()
+  );
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::LieGroup
+SGal3TangentBase<_Derived>::retract(OptJacobianRef J_m_t) const {
+  return exp(J_m_t);
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::LieAlg
+SGal3TangentBase<_Derived>::hat() const {
+  LieAlg sgal3;
+
+  sgal3.template topLeftCorner<3, 3>() = skew(ang());
+  sgal3.template block<3, 1>(0, 3) = lin2();
+  sgal3.template topRightCorner<3, 1>() = lin();
+  sgal3(3, 4) = t();
+
+  sgal3.template bottomLeftCorner<2, 4>().setZero();
+  sgal3(4, 4) = Scalar(0);
+
+  return sgal3;
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::Jacobian
+SGal3TangentBase<_Derived>::rjac() const {
+
+  return (-*this).ljac();
+
+  // Those were verified against auto diff
+
+  // Jacobian Jr = Jacobian::Zero();
+  // Jr.template topLeftCorner<3, 3>() = asSO3().rjac();
+  // // Jr.template block<3, 3>(0, 3) = ??;
+  // // Jr.template block<3, 3>(0, 6) = ??;
+
+  // // Jr.template block<3, 1>(0, 9) = ??;
+
+  // Jr.template block<3, 3>(3, 3) = Jr.template topLeftCorner<3,3>();
+  // SE3Tangent<Scalar>::fillQ(
+  //   Jr.template block<3, 3>(3, 6), -coeffs().template segment<6>(3)
+  // );
+
+  // Jr.template block<3, 3>(6, 6) = Jr.template topLeftCorner<3,3>();
+
+  // Jr(9, 9) = Scalar(1);
+
+  // Jr.template bottomLeftCorner<7, 3>().setZero();
+  // Jr.template block<4, 3>(6, 3).setZero();
+  // Jr.template block<1, 3>(9, 6).setZero();
+  // Jr.template block<6, 1>(3, 9).setZero();
+
+  // return Jr;
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::Jacobian
+SGal3TangentBase<_Derived>::ljac() const {
+  using ConstRef33 = const Eigen::Ref<const Eigen::Matrix<Scalar, 3, 3>>;
+  using ConstRef61 = const Eigen::Ref<const Eigen::Matrix<Scalar, 6, 1>>;
+
+  using Diag = typename Eigen::DiagonalMatrix<Scalar, 3>;
+  auto I33 = [](const Scalar d){ return Diag(d, d, d).toDenseMatrix(); };
+
+  using std::sqrt;
+  using std::cos;
+  using std::sin;
+
+  /** Structure of the left Jacobian according to J. Kelly
+   *
+   * Jl = [ D -L*t  N   E*nu
+   *        0   D   M   0
+   *        0   0   D   0
+   *        0   0   0   1 ]
+   *
+   * with N = N1 - N2.
+   *
+   * Tangent space is tau = [rho ; nu ; theta ; t] in R^10
+   *
+   * Matrix blocks D, E, L, M, N, N1, N2 are referred to in the comments and
+   * correspond to eqs. in Kelly's paper:
+   *
+   *    D:  (18) = Jl_SO3(theta)
+   *    E:  (19)
+   *    L:  (32)
+   *    M:  (33) = Q(nu,theta)
+   *    N:  (34) = N1 - N2
+   *    N1: (35) = Q(rho,theta)
+   *    N2: (36)
+   *
+   * Note that we use the following temporary blocks for computation
+   *
+   * Jl = [ .  .  E   .
+   *        V  .  .  rho
+   *        W W^2 . theta
+   *        .  .  .   .   ]
+   *
+   */
+
+  Jacobian Jl;
+
+  // theta vector
+  const Eigen::Map<const SO3Tangent<Scalar>> so3 = asSO3();
+
+  // Skew matrix W = theta^
+  Jl.template block<3, 3>(3, 0) = so3.hat();
+  ConstRef33 W = Jl.template block<3, 3>(3, 0);
+
+  // Skew matrix W^2
+  Jl.template block<3, 3>(6, 3) = W * W;
+  ConstRef33 WW = Jl.template block<3, 3>(6, 3);
+
+  // Skew matrix V = nu^
+  Jl.template block<3, 3>(6, 0) = skew(lin2());
+  ConstRef33 V = Jl.template block<3, 3>(6, 0);
+
+  // Angles and trigonometry
+  const Scalar theta_sq = so3.coeffs().squaredNorm();
+  // rotation angle
+  const Scalar theta = sqrt(theta_sq);
+  const Scalar theta_cu = theta * theta_sq;
+
+  const Scalar sin_t = sin(theta);
+  const Scalar cos_t = cos(theta);
+
+  // Blocks D
+  Jl.template topLeftCorner<3, 3>() = so3.ljac();
+  Jl.template block<3, 3>(3, 3) = Jl.template topLeftCorner<3, 3>();
+  Jl.template block<3, 3>(6, 6) = Jl.template topLeftCorner<3, 3>();
+
+  // Block E
+  // Note - we use here a temporary block to hold E
+  Jl.template block<3, 3>(0, 6) = I33(Scalar(0.5));
+  if (theta_sq > Constants<Scalar>::eps) {
+    const Scalar A = (theta - sin_t) / theta_sq / theta;
+    const Scalar B = (
+      theta_sq + Scalar(2) * cos_t - Scalar(2)
+    ) / (Scalar(2) * theta_sq * theta_sq);
+
+    Jl.template block<3, 3>(0, 6).noalias() += A * W + B * WW;
+  }
+
+  // Block E * nu
+  Jl.template block<3, 1>(0, 9) = Jl.template block<3, 3>(0, 6) * lin2();
+
+  // Block L
+  Scalar cA, cB;
+  // small angle approx.
+  if (theta_cu > Constants<Scalar>::eps) {
+    cA = (sin_t - theta * cos_t) / theta_cu;
+    cB = (
+      theta_sq + Scalar(2) * (Scalar(1) - theta * sin_t - cos_t)
+    ) / (Scalar(2) * theta_sq * theta_sq);
+  } else {
+    cA = Scalar(1./3.)  - Scalar(1./30.) * theta_sq;
+    cB = Scalar(1./8.);
+  }
+
+  // Block - L * t
+  Jl.template block<3, 3>(0, 3).noalias() = -t() * (
+    // Block L
+    I33(Scalar(0.5)) + cA * W + cB * WW
+  );
+
+  // Block M = Q(nu, theta)
+  SE3Tangent<Scalar>::fillQ(
+    Jl.template block<3, 3>(3, 6), coeffs().template segment<6>(3)
+  );
+
+  // Block N1, part of N. N1 = Q(rho, theta)
+  Jl.template block<6, 1>(3, 9) << lin(), ang();
+  ConstRef61 rho_theta = Jl.template block<6, 1>(3, 9);
+  // block N1 = Q(rho,theta)
+  SE3Tangent<Scalar>::fillQ(Jl.template block<3, 3>(0, 6), rho_theta);
+
+  // Block N2, part of N
+  Scalar cC, cD, cE, cF;
+  if (theta_cu > Constants<Scalar>::eps) {
+    cA = (Scalar(2) - theta * sin_t - Scalar(2) * cos_t) / theta_cu / theta;
+    cB = (
+      theta_cu + Scalar(6) * theta + Scalar(6) * theta * cos_t - Scalar(12) * sin_t
+    ) / (Scalar(6) * theta_cu * theta_sq);
+    cC = (
+      Scalar(12) * sin_t - theta_cu - Scalar(3) * theta_sq * sin_t - Scalar(12) * theta * cos_t
+    ) / (Scalar(6) * theta_cu * theta_sq);
+    cD = (
+      Scalar(4) + theta_sq * (Scalar(1) + cos_t) - Scalar(4) * (theta * sin_t + cos_t)
+    ) / (Scalar(2) * theta_cu * theta_cu);
+    cE = (theta_sq + Scalar(2) * (cos_t - Scalar(1))) / (Scalar(2) * theta_cu * theta);
+    cF = (theta_cu + Scalar(6) * (sin_t - theta)) / (Scalar(6) * theta_cu * theta_sq);
+  } else {
+    cA = Scalar(1. / 12.);
+    cB = Scalar(1. / 24.);
+    cC = Scalar(1. / 10.);
+    cD = Scalar(1. / 240.);
+    cE = Scalar(1. / 24.);
+    cF = Scalar(1. / 120.);
+  }
+
+  // Block N = N1 - N2
+  Jl.template block<3, 3>(0, 6) -= (
+    // Block N2
+    t() / Scalar(6) * V
+    + (cA * W + cB * WW) * (t() * V)
+    + cC * (W * V * (t() * W))
+    + cD * (WW * V * (t() * W))
+    + t() * V * (cE * W + cF * WW)
+  );
+
+  // Block 1
+  Jl(9, 9) = Scalar(1);
+
+  // Blocks of zeros
+  Jl.template bottomLeftCorner<7, 3>().setZero();
+  Jl.template block<4, 3>(6, 3).setZero();
+  Jl.template block<1, 3>(9, 6).setZero();
+  Jl.template block<6, 1>(3, 9).setZero();
+
+  return Jl;
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::Jacobian
+SGal3TangentBase<_Derived>::smallAdj() const {
+  Jacobian smallAdj;
+
+  smallAdj.template topLeftCorner<3,3>() = skew(ang());
+  smallAdj.template block<3, 3>(0, 3) = -t() * Eigen::Matrix3d::Identity();
+  smallAdj.template block<3, 3>(0, 6) = skew(lin());
+  smallAdj.template block<3, 1>(0, 9) = lin2();
+
+  smallAdj.template block<3, 3>(3, 3) = smallAdj.template topLeftCorner<3,3>();
+  smallAdj.template block<3, 3>(3, 6) = skew(lin2());
+
+  smallAdj.template block<3, 3>(6, 6) = smallAdj.template topLeftCorner<3,3>();
+
+  smallAdj.template block<7, 3>(3, 0).setZero();
+  smallAdj.template block<4, 3>(6, 3).setZero();
+
+  smallAdj.template block<1, 3>(9, 6).setZero();
+  smallAdj.template block<7, 1>(3, 9).setZero();
+
+  return smallAdj;
+}
+
+// SGal3Tangent specific API
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::LinBlock
+SGal3TangentBase<_Derived>::lin() {
+  return coeffs().template head<3>();
+}
+
+template <typename _Derived>
+const typename SGal3TangentBase<_Derived>::ConstLinBlock
+SGal3TangentBase<_Derived>::lin() const {
+  return coeffs().template head<3>();
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::LinBlock
+SGal3TangentBase<_Derived>::lin2() {
+  return coeffs().template segment<3>(3);
+}
+
+template <typename _Derived>
+const typename SGal3TangentBase<_Derived>::ConstLinBlock
+SGal3TangentBase<_Derived>::lin2() const {
+  return coeffs().template segment<3>(3);
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::AngBlock
+SGal3TangentBase<_Derived>::ang() {
+  return coeffs().template segment<3>(6);
+}
+
+template <typename _Derived>
+const typename SGal3TangentBase<_Derived>::ConstAngBlock
+SGal3TangentBase<_Derived>::ang() const {
+  return coeffs().template segment<3>(6);
+}
+
+template <typename _Derived>
+typename SGal3TangentBase<_Derived>::Scalar
+SGal3TangentBase<_Derived>::t() const {
+  return coeffs()(9);
+}
+
+template <typename _Derived>
+void SGal3TangentBase<_Derived>::fillE(
+  Eigen::Ref<Eigen::Matrix<Scalar, 3, 3>> E,
+  const Eigen::Map<const SO3Tangent<Scalar>>& so3
+) {
+  using I = typename Eigen::DiagonalMatrix<Scalar, 3>;
+
+  const Scalar theta_sq = so3.coeffs().squaredNorm();
+
+  E.noalias() = I(Scalar(0.5), Scalar(0.5), Scalar(0.5)).toDenseMatrix();
+
+  // small angle approx.
+  if (theta_sq < Constants<Scalar>::eps) {
+    return;
+  }
+
+  const Scalar theta = sqrt(theta_sq); // rotation angle
+
+  const Scalar A = (theta - sin(theta)) / theta_sq / theta;
+  const Scalar B = (theta_sq + Scalar(2) * cos(theta) - Scalar(2)) / (Scalar(2) * theta_sq * theta_sq);
+
+  const typename SO3Tangent<Scalar>::LieAlg W = so3.hat();
+
+  E.noalias() += A * W + B * W * W;
+}
+
+namespace internal {
+
+//! @brief Generator specialization for SGal3TangentBase objects.
+template <typename Derived>
+struct GeneratorEvaluator<SGal3TangentBase<Derived>> {
+  static typename SGal3TangentBase<Derived>::LieAlg
+  run(const unsigned int i) {
+    using LieAlg = typename SGal3TangentBase<Derived>::LieAlg;
+    using Scalar = typename SGal3TangentBase<Derived>::Scalar;
+
+    switch (i) {
+      case 0: {
+        static const LieAlg E0(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(1),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+
+          ).finished()
+        );
+        return E0;
+      }
+      case 1: {
+        static const LieAlg E1(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(1),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E1;
+      }
+      case 2: {
+        static const LieAlg E2(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(1),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E2;
+      }
+      case 3: {
+        static const LieAlg E3(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(1), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E3;
+      }
+      case 4: {
+        static const LieAlg E4(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(1), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E4;
+      }
+      case 5: {
+        static const LieAlg E5(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(1), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E5;
+      }
+      case 6: {
+        static const LieAlg E6(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar( 0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(-1), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(1), Scalar( 0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar( 0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar( 0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E6;
+      }
+      case 7: {
+        static const LieAlg E7(
+          (
+            LieAlg() <<
+              Scalar( 0), Scalar(0), Scalar(1), Scalar(0), Scalar(0),
+              Scalar( 0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(-1), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar( 0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar( 0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E7;
+      }
+      case 8: {
+        static const LieAlg E8(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(-1), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(1), Scalar( 0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar( 0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar( 0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar( 0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E8;
+      }
+      case 9: {
+        static const LieAlg E9(
+          (
+            LieAlg() <<
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(1),
+              Scalar(0), Scalar(0), Scalar(0), Scalar(0), Scalar(0)
+          ).finished()
+        );
+        return E9;
+      }
+      default:
+        MANIF_THROW("Index i must be in [0,9]!", invalid_argument);
+        break;
+    }
+
+    return LieAlg{};
+  }
+};
+
+//! @brief Random specialization for SGal3TangentBase objects.
+template <typename Derived>
+struct RandomEvaluatorImpl<SGal3TangentBase<Derived>> {
+  static void run(SGal3TangentBase<Derived>& m) {
+    // in [-1,1]
+    m.coeffs().setRandom();
+    // In ball of radius PI
+    m.coeffs().template segment<3>(6) = randPointInBall(MANIF_PI).template cast<typename Derived::Scalar>();
+  }
+};
+
+} // namespace internal
+} // namespace manif
+
+#endif // _MANIF_MANIF_SGAL3TANGENT_BASE_H_
diff --git a/include/manif/impl/sgal3/SGal3Tangent_map.h b/include/manif/impl/sgal3/SGal3Tangent_map.h
new file mode 100644
index 00000000..74fc04bd
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3Tangent_map.h
@@ -0,0 +1,85 @@
+#ifndef _MANIF_MANIF_SGAL3TANGENT_MAP_H_
+#define _MANIF_MANIF_SGAL3TANGENT_MAP_H_
+
+#include "manif/impl/sgal3/SGal3Tangent.h"
+
+namespace manif {
+namespace internal {
+
+//! @brief traits specialization for Eigen Map
+template <typename _Scalar>
+struct traits<Eigen::Map<SGal3Tangent<_Scalar>, 0> >
+  : public traits<SGal3Tangent<_Scalar>> {
+  using typename traits<SGal3Tangent<_Scalar>>::Scalar;
+  using traits<SGal3Tangent<_Scalar>>::DoF;
+  using DataType = Eigen::Map<Eigen::Matrix<Scalar, DoF, 1>, 0>;
+  using Base = SGal3TangentBase<Eigen::Map<SGal3Tangent<Scalar>, 0>>;
+};
+
+//! @brief traits specialization for Eigen Map
+template <typename _Scalar>
+struct traits<Eigen::Map<const SGal3Tangent<_Scalar>, 0> >
+  : public traits<const SGal3Tangent<_Scalar>> {
+  using typename traits<const SGal3Tangent<_Scalar>>::Scalar;
+  using traits<const SGal3Tangent<_Scalar>>::DoF;
+  using DataType = Eigen::Map<const Eigen::Matrix<Scalar, DoF, 1>, 0>;
+  using Base = SGal3TangentBase<Eigen::Map<const SGal3Tangent<Scalar>, 0>>;
+};
+
+} // namespace internal
+} // namespace manif
+
+namespace Eigen {
+
+/**
+ * @brief Specialization of Map for manif::SGal3
+ */
+template <class _Scalar>
+class Map<manif::SGal3Tangent<_Scalar>, 0>
+  : public manif::SGal3TangentBase<Map<manif::SGal3Tangent<_Scalar>, 0> > {
+  using Base = manif::SGal3TangentBase<Map<manif::SGal3Tangent<_Scalar>, 0> >;
+
+public:
+
+  MANIF_TANGENT_TYPEDEF
+  MANIF_INHERIT_TANGENT_API
+  MANIF_INHERIT_TANGENT_OPERATOR
+
+  Map(Scalar* coeffs) : data_(coeffs) { }
+
+  MANIF_TANGENT_MAP_ASSIGN_OP(SGal3Tangent)
+
+  DataType& coeffs() { return data_; }
+  const DataType& coeffs() const { return data_; }
+
+protected:
+
+  DataType data_;
+};
+
+/**
+ * @brief Specialization of Map for const manif::SGal3
+ */
+template <class _Scalar>
+class Map<const manif::SGal3Tangent<_Scalar>, 0>
+  : public manif::SGal3TangentBase<Map<const manif::SGal3Tangent<_Scalar>, 0> > {
+  using Base = manif::SGal3TangentBase<Map<const manif::SGal3Tangent<_Scalar>, 0> >;
+
+public:
+
+  MANIF_TANGENT_TYPEDEF
+  MANIF_INHERIT_TANGENT_API
+  MANIF_INHERIT_TANGENT_OPERATOR
+
+  Map(const Scalar* coeffs) : data_(coeffs) { }
+
+  const DataType& coeffs() const { return data_; }
+
+protected:
+
+  const DataType data_;
+};
+
+} // namespace Eigen
+
+#endif // _MANIF_MANIF_SGAL3TANGENT_MAP_H_
diff --git a/include/manif/impl/sgal3/SGal3_base.h b/include/manif/impl/sgal3/SGal3_base.h
new file mode 100644
index 00000000..07e7e044
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3_base.h
@@ -0,0 +1,484 @@
+#ifndef _MANIF_MANIF_SGAL3_BASE_H_
+#define _MANIF_MANIF_SGAL3_BASE_H_
+
+#include "manif/impl/sgal3/SGal3_properties.h"
+#include "manif/impl/lie_group_base.h"
+#include "manif/impl/so3/SO3_map.h"
+#include "manif/impl/se3/SE3_map.h"
+
+namespace manif {
+
+//
+// LieGroup
+//
+
+/**
+ * @brief The base class of the SGal3 group.
+ * @note See "All About the Galilean Group SGal(3)" J. Kelly.
+ * https://arxiv.org/abs/2312.07555
+ *
+ */
+template <typename _Derived>
+struct SGal3Base : LieGroupBase<_Derived> {
+private:
+
+  using Base = LieGroupBase<_Derived>;
+  using Type = SGal3Base<_Derived>;
+
+public:
+
+  MANIF_GROUP_TYPEDEF
+  MANIF_INHERIT_GROUP_AUTO_API
+  MANIF_INHERIT_GROUP_OPERATOR
+
+  using Base::coeffs;
+
+  using Rotation       = typename internal::traits<_Derived>::Rotation;
+  using Translation    = typename internal::traits<_Derived>::Translation;
+  using LinearVelocity = typename internal::traits<_Derived>::LinearVelocity;
+  using Time           = Scalar;
+  using Transformation = Eigen::Matrix<Scalar, 5, 5>;
+  using Isometry       = Eigen::Matrix<Scalar, 5, 5>; /**< Double direct spatial isometry*/
+  using QuaternionDataType = Eigen::Quaternion<Scalar>;
+
+  // LieGroup common API
+
+protected:
+
+  using Base::derived;
+
+  MANIF_DEFAULT_CONSTRUCTOR(SGal3Base)
+
+public:
+
+  MANIF_GROUP_ML_ASSIGN_OP(SGal3Base)
+
+  /**
+   * @brief Get the inverse.
+   * @param[out] -optional- J_minv_m Jacobian of the inverse wrt this.
+   */
+  LieGroup inverse(OptJacobianRef J_minv_m = {}) const;
+
+  /**
+   * @brief Get the SGal3 corresponding Lie algebra element in vector form.
+   * @param[out] -optional- J_t_m Jacobian of the tangent wrt to this.
+   * @return The SGal3 tangent of this.
+   * @note This is the log() map in vector form.
+   * @see SGal3Tangent.
+   */
+  Tangent log(OptJacobianRef J_t_m = {}) const;
+
+  /**
+   * @brief This function is deprecated.
+   * Please considere using
+   * @ref log instead.
+   */
+  MANIF_DEPRECATED
+  Tangent lift(OptJacobianRef J_t_m = {}) const;
+
+  /**
+   * @brief Composition of this and another SGal3 element.
+   * @param[in] m Another SGal3 element.
+   * @param[out] -optional- J_mc_ma Jacobian of the composition wrt this.
+   * @param[out] -optional- J_mc_mb Jacobian of the composition wrt m.
+   * @return The composition of 'this . m'.
+   */
+  template <typename _DerivedOther>
+  LieGroup compose(
+    const LieGroupBase<_DerivedOther>& m,
+    OptJacobianRef J_mc_ma = {},
+    OptJacobianRef J_mc_mb = {}
+  ) const;
+
+  /**
+   * @brief Get the action
+   * @param[in] p A 3D point.
+   * @param[out] -optional- J_pout_m The Jacobian of the new object wrt this.
+   * @param[out] -optional- J_pout_p The Jacobian of the new object wrt input object.
+   */
+  template <typename _EigenDerived>
+  Eigen::Matrix<Scalar, 3, 1>
+  act(
+    const Eigen::MatrixBase<_EigenDerived> &p,
+    tl::optional<Eigen::Ref<Eigen::Matrix<Scalar, 3, 10>>> J_pout_m = {},
+    tl::optional<Eigen::Ref<Eigen::Matrix<Scalar, 3, 3>>> J_pout_p = {}
+  ) const;
+
+  /**
+   * @brief Get the adjoint matrix of SGal3 at this.
+   */
+  Jacobian adj() const;
+
+  // SGal3 specific functions
+
+  /**
+   * Get the isometry object (double direct isometry).
+   * @note T = | R v t|
+   *           |   1 s|
+   *           |     1|
+   */
+  Transformation transform() const;
+
+  /**
+   * Get the isometry object (double direct isometry).
+   * @note T = | R v t|
+   *           |   1 s|
+   *           |     1|
+   */
+  Isometry isometry() const;
+
+  /**
+   * @brief Get the rotational part of this as a rotation matrix.
+   */
+  Rotation rotation() const;
+
+  /**
+   * @brief Get the rotational part of this as a quaternion.
+   */
+  QuaternionDataType quat() const;
+
+  /**
+   * @brief Get the translational part in vector form.
+   */
+  Translation translation() const;
+
+  /**
+   * @brief Get the x component of the translational part.
+   */
+  Scalar x() const;
+
+  /**
+   * @brief Get the y component of translational part.
+   */
+  Scalar y() const;
+
+  /**
+   * @brief Get the z component of translational part.
+   */
+  Scalar z() const;
+
+  /**
+   * @brief Get the linear velocity part in vector form.
+   */
+  LinearVelocity linearVelocity() const;
+
+  /**
+   * @brief Get the x component of the linear velocity part.
+   */
+  Scalar vx() const;
+
+  /**
+   * @brief Get the y component of linear velocity part.
+   */
+  Scalar vy() const;
+
+  /**
+   * @brief Get the z component of linear velocity part.
+   */
+  Scalar vz() const;
+
+  /**
+   * @brief Get the time.
+   */
+  Scalar t() const;
+
+  /**
+   * @brief Normalize the underlying quaternion.
+   */
+  void normalize();
+
+public: /// @todo make protected
+
+  Eigen::Map<const SO3<Scalar>> asSO3() const {
+    return Eigen::Map<const SO3<Scalar>>(coeffs().data()+3);
+  }
+
+  Eigen::Map<SO3<Scalar>> asSO3() {
+    return Eigen::Map<SO3<Scalar>>(coeffs().data()+3);
+  }
+};
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Transformation
+SGal3Base<_Derived>::transform() const {
+  Eigen::Matrix<Scalar, 5, 5> T;
+  T.template topLeftCorner<3, 3>() = rotation();
+  T.template block<3, 1>(0, 3) = linearVelocity();
+  T.template topRightCorner<3, 1>() = translation();
+  T.template bottomLeftCorner<2, 3>().setZero();
+  T.template bottomRightCorner<2, 2>().setIdentity();
+  T(3, 4) = t();
+  return T;
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Isometry
+SGal3Base<_Derived>::isometry() const {
+  return Isometry(transform());
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Rotation
+SGal3Base<_Derived>::rotation() const {
+  return asSO3().rotation();
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::QuaternionDataType
+SGal3Base<_Derived>::quat() const {
+  return asSO3().quat();
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Translation
+SGal3Base<_Derived>::translation() const {
+  return coeffs().template head<3>();
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::LinearVelocity
+SGal3Base<_Derived>::linearVelocity() const {
+  return coeffs().template segment<3>(7);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::LieGroup
+SGal3Base<_Derived>::inverse(OptJacobianRef J_minv_m) const {
+  if (J_minv_m) {
+    (*J_minv_m) = -adj();
+  }
+
+  const SO3<Scalar> so3inv = asSO3().inverse();
+
+  return LieGroup(
+    -so3inv.act((translation()-t()*linearVelocity())),
+     so3inv,
+    -so3inv.act(linearVelocity()),
+    -t()
+  );
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Tangent
+SGal3Base<_Derived>::log(OptJacobianRef J_t_m) const {
+  const SO3Tangent<Scalar> so3tan = asSO3().log();
+
+  Eigen::Matrix<Scalar, 3, 3> E;
+  Tangent::fillE(E, Eigen::Map<const SO3Tangent<Scalar>>(so3tan.data()));
+
+  const LinearVelocity nu = so3tan.ljacinv() * linearVelocity();
+
+  Tangent tan(
+    (
+      typename Tangent::DataType() <<
+        so3tan.ljacinv() * (translation() - E * (t() * nu)), nu, so3tan.coeffs(), t()
+    ).finished()
+  );
+
+  if (J_t_m) {
+    // Jr^-1
+    (*J_t_m) = tan.rjacinv();
+  }
+
+  return tan;
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Tangent
+SGal3Base<_Derived>::lift(OptJacobianRef J_t_m) const {
+  return log(J_t_m);
+}
+
+template <typename _Derived>
+template <typename _DerivedOther>
+typename SGal3Base<_Derived>::LieGroup
+SGal3Base<_Derived>::compose(
+  const LieGroupBase<_DerivedOther>& m,
+  OptJacobianRef J_mc_ma,
+  OptJacobianRef J_mc_mb
+) const {
+  static_assert(
+    std::is_base_of<SGal3Base<_DerivedOther>, _DerivedOther>::value,
+    "Argument does not inherit from SGal3Base !"
+  );
+
+  const auto& m_sgal3 = static_cast<const SGal3Base<_DerivedOther>&>(m);
+
+  if (J_mc_ma) {
+    (*J_mc_ma) = m.inverse().adj();
+  }
+
+  if (J_mc_mb) {
+    J_mc_mb->setIdentity();
+  }
+
+  return LieGroup(
+    rotation() * m_sgal3.translation() + m_sgal3.t() * linearVelocity() + translation(),
+    asSO3() * m_sgal3.asSO3(),
+    rotation() * m_sgal3.linearVelocity() + linearVelocity(),
+    t() + m_sgal3.t()
+  );
+}
+
+template <typename _Derived>
+template <typename _EigenDerived>
+Eigen::Matrix<typename SGal3Base<_Derived>::Scalar, 3, 1>
+SGal3Base<_Derived>::act(
+  const Eigen::MatrixBase<_EigenDerived> &p,
+  tl::optional<Eigen::Ref<Eigen::Matrix<Scalar, 3, 10>>> J_pout_m,
+  tl::optional<Eigen::Ref<Eigen::Matrix<Scalar, 3, 3>>> J_pout_p
+) const {
+  assert_vector_dim(p, 3);
+
+  const Rotation R(rotation());
+
+  if (J_pout_m) {
+    J_pout_m->template topLeftCorner<3, 3>() = R;
+    J_pout_m->template block<3, 3>(0, 3).setZero();
+    J_pout_m->template block<3, 3>(0, 6).noalias() = -R * skew(p);
+    J_pout_m->template topRightCorner<3, 1>() = linearVelocity();
+  }
+
+  if (J_pout_p) {
+    (*J_pout_p) = R;
+  }
+
+  return translation() + R * p;
+}
+
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Jacobian
+SGal3Base<_Derived>::adj() const {
+  ///
+  /// this is
+  ///       Ad(g) = | R -R.tau [(t-v.tau)]x.R v|
+  ///               | 0   R        [v]x.R     0|
+  ///               | 0   0          R        0|
+  ///               | 0   0          0        1|
+  ///
+  /// considering vee(log(g)) = (rho;v;w;iota)
+
+  Jacobian Adj;
+  Adj.template topLeftCorner<3, 3>() = rotation();
+  Adj.template block<3, 3>(0, 3).noalias() = -t() * Adj.template topLeftCorner<3, 3>();
+  Adj.template block<3, 3>(0, 6).noalias() =
+    skew(translation() - t() * linearVelocity()) * Adj.template topLeftCorner<3, 3>();
+  Adj.template topRightCorner<3, 1>() = linearVelocity();
+
+  Adj.template block<3, 3>(3, 3) = Adj.template topLeftCorner<3, 3>();
+  Adj.template block<3, 3>(3, 6).noalias() =
+    skew(linearVelocity()) * Adj.template topLeftCorner<3, 3>();
+
+  Adj.template block<3,  3>(6, 6) = Adj.template topLeftCorner<3, 3>();
+
+  Adj.template bottomLeftCorner<7, 3>().setZero();
+  Adj.template block<4, 3>(6, 3).setZero();
+  Adj.template block<1, 3>(9, 6).setZero();
+  Adj.template block<6, 1>(3, 9).setZero();
+
+  Adj(9, 9) = Scalar(1);
+
+  return Adj;
+}
+
+// SGal3 specific function
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::x() const {
+  return coeffs()(0);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::y() const {
+  return coeffs()(1);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::z() const {
+  return coeffs()(2);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::vx() const {
+  return coeffs()(7);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::vy() const {
+  return coeffs()(8);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::vz() const {
+  return coeffs()(9);
+}
+
+template <typename _Derived>
+typename SGal3Base<_Derived>::Scalar
+SGal3Base<_Derived>::t() const {
+  return coeffs()(10);
+}
+
+template <typename _Derived>
+void SGal3Base<_Derived>::normalize() {
+  coeffs().template segment<4>(3).normalize();
+}
+
+namespace internal {
+
+//! @brief Random specialization for SGal3Base objects.
+template <typename Derived>
+struct RandomEvaluatorImpl<SGal3Base<Derived>> {
+  template <typename T>
+  static void run(T& m) {
+    using Scalar = typename SGal3Base<Derived>::Scalar;
+    using LieGroup = typename SGal3Base<Derived>::LieGroup;
+
+    typename LieGroup::DataType data = LieGroup::DataType::Random();
+    data.template segment<4>(3) = randQuat<Scalar>().coeffs();
+
+    m = LieGroup(data);
+  }
+};
+
+//! @brief Assignment assert specialization for SGal3Base objects
+template <typename Derived>
+struct AssignmentEvaluatorImpl<SGal3Base<Derived>> {
+  template <typename T>
+  static void run_impl(const T& data) {
+    using std::abs;
+    MANIF_ASSERT(
+      abs(data.template segment<4>(3).norm()-typename SGal3Base<Derived>::Scalar(1)) <
+      Constants<typename SGal3Base<Derived>::Scalar>::eps,
+      "SGal3 assigned data not normalized !",
+      manif::invalid_argument
+    );
+    MANIF_UNUSED_VARIABLE(data);
+  }
+};
+
+//! @brief Cast specialization for SGal3Base objects.
+template <typename Derived, typename NewScalar>
+struct CastEvaluatorImpl<SGal3Base<Derived>, NewScalar> {
+  template <typename T>
+  static auto run(const T& o) -> typename Derived::template LieGroupTemplate<NewScalar> {
+    return typename Derived::template LieGroupTemplate<NewScalar>(
+      o.translation().template cast<NewScalar>(),
+      o.quat().template cast<NewScalar>().normalized(),
+      o.linearVelocity().template cast<NewScalar>(),
+      NewScalar(o.t())
+    );
+  }
+};
+
+} // namespace internal
+} // namespace manif
+
+#endif // _MANIF_MANIF_SGAL3_BASE_H_
diff --git a/include/manif/impl/sgal3/SGal3_map.h b/include/manif/impl/sgal3/SGal3_map.h
new file mode 100644
index 00000000..6f28b9b7
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3_map.h
@@ -0,0 +1,84 @@
+#ifndef _MANIF_MANIF_SGAL3_MAP_H_
+#define _MANIF_MANIF_SGAL3_MAP_H_
+
+#include "manif/impl/sgal3/SGal3.h"
+
+namespace manif {
+namespace internal {
+
+//! @brief traits specialization for Eigen Map
+template <typename _Scalar>
+struct traits<Eigen::Map<SGal3<_Scalar>, 0> > : public traits<SGal3<_Scalar>> {
+  using typename traits<SGal3<_Scalar>>::Scalar;
+  using traits<SGal3<Scalar>>::RepSize;
+  using Base = SGal3Base<Eigen::Map<SGal3<Scalar>, 0>>;
+  using DataType = Eigen::Map<Eigen::Matrix<Scalar, RepSize, 1>, 0>;
+};
+
+//! @brief traits specialization for Eigen Map const
+template <typename _Scalar>
+struct traits<Eigen::Map<const SGal3<_Scalar>,0> >
+  : public traits<const SGal3<_Scalar>> {
+  using typename traits<const SGal3<_Scalar>>::Scalar;
+  using traits<const SGal3<Scalar>>::RepSize;
+  using Base = SGal3Base<Eigen::Map<const SGal3<Scalar>, 0>>;
+  using DataType = Eigen::Map<const Eigen::Matrix<Scalar, RepSize, 1>, 0>;
+};
+
+} // namespace internal
+} // namespace manif
+
+namespace Eigen {
+
+/**
+ * @brief Specialization of Map for manif::SGal3
+ */
+template <class _Scalar>
+class Map<manif::SGal3<_Scalar>, 0>
+  : public manif::SGal3Base<Map<manif::SGal3<_Scalar>, 0> > {
+  using Base = manif::SGal3Base<Map<manif::SGal3<_Scalar>, 0> >;
+
+public:
+
+  MANIF_COMPLETE_GROUP_TYPEDEF
+  MANIF_INHERIT_GROUP_API
+  using Base::rotation;
+
+  Map(Scalar* coeffs) : data_(coeffs) { }
+
+  MANIF_GROUP_MAP_ASSIGN_OP(SGal3)
+
+  DataType& coeffs() { return data_; }
+  const DataType& coeffs() const { return data_; }
+
+protected:
+
+  DataType data_;
+};
+
+/**
+ * @brief Specialization of Map for const manif::SGal3
+ */
+template <class _Scalar>
+class Map<const manif::SGal3<_Scalar>, 0>
+  : public manif::SGal3Base<Map<const manif::SGal3<_Scalar>, 0> > {
+  using Base = manif::SGal3Base<Map<const manif::SGal3<_Scalar>, 0> >;
+
+public:
+
+  MANIF_COMPLETE_GROUP_TYPEDEF
+  MANIF_INHERIT_GROUP_API
+  // using Base::rotation;
+
+  Map(const Scalar* coeffs) : data_(coeffs) { }
+
+  const DataType& coeffs() const { return data_; }
+
+protected:
+
+  const DataType data_;
+};
+
+} // namespace Eigen
+
+#endif // _MANIF_MANIF_SGAL3_MAP_H_
diff --git a/include/manif/impl/sgal3/SGal3_properties.h b/include/manif/impl/sgal3/SGal3_properties.h
new file mode 100644
index 00000000..3b30035d
--- /dev/null
+++ b/include/manif/impl/sgal3/SGal3_properties.h
@@ -0,0 +1,31 @@
+#ifndef _MANIF_MANIF_SGAL3_PROPERTIES_H_
+#define _MANIF_MANIF_SGAL3_PROPERTIES_H_
+
+#include "manif/impl/traits.h"
+
+namespace manif {
+
+// Forward declaration
+template <typename _Derived> struct SGal3Base;
+template <typename _Derived> struct SGal3TangentBase;
+
+namespace internal {
+
+//! traits specialization
+template <typename _Derived>
+struct LieGroupProperties<SGal3Base<_Derived>> {
+  static constexpr int Dim = 3; /// @brief Space dimension
+  static constexpr int DoF = 10; /// @brief Degrees of freedom
+};
+
+//! traits specialization
+template <typename _Derived>
+struct LieGroupProperties<SGal3TangentBase<_Derived>> {
+  static constexpr int Dim = 3; /// @brief Space dimension
+  static constexpr int DoF = 10; /// @brief Degrees of freedom
+};
+
+} // namespace internal
+} // namespace manif
+
+#endif // _MANIF_MANIF_SGAL3_PROPERTIES_H_
diff --git a/include/manif/manif.h b/include/manif/manif.h
index 5e9f0148..74be91ed 100644
--- a/include/manif/manif.h
+++ b/include/manif/manif.h
@@ -10,6 +10,7 @@
 #include "manif/SE3.h"
 #include "manif/Rn.h"
 #include "manif/SE_2_3.h"
+#include "manif/SGal3.h"
 
 #include "manif/Bundle.h"
 
diff --git a/python/CMakeLists.txt b/python/CMakeLists.txt
index 046e5dae..c5d76452 100644
--- a/python/CMakeLists.txt
+++ b/python/CMakeLists.txt
@@ -5,6 +5,7 @@ pybind11_add_module(manifpy MODULE
   bindings_se2.cpp
   bindings_se3.cpp
   bindings_se_2_3.cpp
+  bindings_sgal3.cpp
   bindings_manif.cpp
 )
 target_link_libraries(manifpy PRIVATE ${PROJECT_NAME})
diff --git a/python/bindings_manif.cpp b/python/bindings_manif.cpp
index d1b16d56..fd075950 100644
--- a/python/bindings_manif.cpp
+++ b/python/bindings_manif.cpp
@@ -10,6 +10,8 @@ void wrap_SE3(pybind11::module &m);
 
 void wrap_SE_2_3(pybind11::module &m);
 
+void wrap_SGal3(pybind11::module &m);
+
 PYBIND11_MODULE(_bindings, m) {
   m.doc() = "Python bindings for the manif library, "
             "a small library for Lie theory.";
@@ -23,4 +25,6 @@ PYBIND11_MODULE(_bindings, m) {
   wrap_SE3(m);
 
   wrap_SE_2_3(m);
+
+  wrap_SGal3(m);
 }
diff --git a/python/bindings_sgal3.cpp b/python/bindings_sgal3.cpp
new file mode 100644
index 00000000..b42ae205
--- /dev/null
+++ b/python/bindings_sgal3.cpp
@@ -0,0 +1,73 @@
+#include <pybind11/pybind11.h>
+#include <pybind11/operators.h>
+#include <pybind11/eigen.h>
+#include <pybind11/stl.h>
+
+#include "manif/SGal3.h"
+
+#include "bindings_optional.h"
+#include "bindings_lie_group_base.h"
+#include "bindings_tangent_base.h"
+
+namespace py = pybind11;
+
+void wrap_SGal3(py::module &m) {
+  using Scalar = manif::SGal3d::Scalar;
+  using Translation = manif::SGal3d::Translation;
+  using Quaternion = Eigen::Quaternion<Scalar>;
+  using LinearVelocity = manif::SGal3d::LinearVelocity;
+
+  py::class_<
+    manif::LieGroupBase<manif::SGal3d>,
+    std::unique_ptr<manif::LieGroupBase<manif::SGal3d>, py::nodelete>
+  > SGal3_base(m, "_SGal3Base");
+  py::class_<
+    manif::TangentBase<manif::SGal3Tangentd>,
+    std::unique_ptr<manif::TangentBase<manif::SGal3Tangentd>, py::nodelete>
+  > SGal3_tan_base(m, "_SGal3TangentBase");
+
+  py::class_<manif::SGal3d, manif::LieGroupBase<manif::SGal3d>> SGal3(m, "SGal3");
+  py::class_<
+    manif::SGal3Tangentd, manif::TangentBase<manif::SGal3Tangentd>
+  > SGal3_tan(m, "SGal3Tangent");
+
+  //group
+
+  wrap_lie_group_base<manif::SGal3d, manif::LieGroupBase<manif::SGal3d>>(SGal3);
+
+  // SGal3.def(py::init<const Translation&, const Quaternion&, const LinearVelocity&>());
+  // SGal3.def(py::init<const Translation&, const Eigen::AngleAxis<Scalar>&, const LinearVelocity&>());
+  // SGal3.def(py::init<const Translation&, const manif::SO3<Scalar>&, const LinearVelocity&>());
+  SGal3.def(
+    py::init<
+      const Scalar, const Scalar, const Scalar,
+      const Scalar, const Scalar, const Scalar,
+      const Scalar, const Scalar, const Scalar,
+      const Scalar
+    >()
+  );
+  // SGal3.def(py::init<igen::Transform<Scalar, 3, Eigen::Isometry>&, const LinearVelocity&>());
+
+  // SGal3.def("isometry", &manif::SGal3d::isometry);
+  SGal3.def("rotation", &manif::SGal3d::rotation);
+  // SGal3.def("quat", &manif::SGal3d::quat);
+  SGal3.def("translation", &manif::SGal3d::translation);
+  SGal3.def("x", &manif::SGal3d::x);
+  SGal3.def("y", &manif::SGal3d::y);
+  SGal3.def("z", &manif::SGal3d::z);
+  SGal3.def("linearVelocity", &manif::SGal3d::linearVelocity);
+  SGal3.def("vx", &manif::SGal3d::vx);
+  SGal3.def("vy", &manif::SGal3d::vy);
+  SGal3.def("vz", &manif::SGal3d::vz);
+  SGal3.def("t", &manif::SGal3d::t);
+  SGal3.def("normalize", &manif::SGal3d::normalize);
+
+  // tangent
+  wrap_tangent_base<
+    manif::SGal3Tangentd, manif::TangentBase<manif::SGal3Tangentd>
+  >(SGal3_tan);
+
+  // SGal3_tan.def("v", &manif::SE3Tangentd::v);
+  // SGal3_tan.def("w", &manif::SE3Tangentd::w);
+  // SGal3_tan.def("a", &manif::SE3Tangentd::a);
+}
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index a6901922..f0840653 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -77,6 +77,9 @@ add_subdirectory(se3)
 # # SE_2_3 tests
 add_subdirectory(se_2_3)
 
+# # SGal3 tests
+add_subdirectory(sgal3)
+
 if(NOT MSVC)
   # Bundle tests
   add_subdirectory(bundle)
diff --git a/test/autodiff/gtest_common_tester_autodiff.h b/test/autodiff/gtest_common_tester_autodiff.h
index 3165f3a6..af2b749c 100644
--- a/test/autodiff/gtest_common_tester_autodiff.h
+++ b/test/autodiff/gtest_common_tester_autodiff.h
@@ -93,7 +93,8 @@ namespace manif{
   __MANIF_MAKE_TEST_AUTODIFF_ALL_TYPES(SO3)     \
   __MANIF_MAKE_TEST_AUTODIFF_ALL_TYPES(SE2)     \
   __MANIF_MAKE_TEST_AUTODIFF_ALL_TYPES(SE3)     \
-  __MANIF_MAKE_TEST_AUTODIFF_ALL_TYPES(SE_2_3)
+  __MANIF_MAKE_TEST_AUTODIFF_ALL_TYPES(SE_2_3)  \
+  __MANIF_MAKE_TEST_AUTODIFF_ALL_TYPES(SGal3)
 
 namespace manif {
 
diff --git a/test/ceres/CMakeLists.txt b/test/ceres/CMakeLists.txt
index 6e38fe58..3ef30b36 100644
--- a/test/ceres/CMakeLists.txt
+++ b/test/ceres/CMakeLists.txt
@@ -13,6 +13,8 @@ manif_add_gtest(gtest_se3_ceres gtest_se3_ceres.cpp)
 
 manif_add_gtest(gtest_se23_ceres gtest_se23_ceres.cpp)
 
+manif_add_gtest(gtest_sgal3_ceres gtest_sgal3_ceres.cpp)
+
 manif_add_gtest(gtest_bundle_ceres gtest_bundle_ceres.cpp)
 
 set(CXX_TEST_TARGETS_CERES
@@ -35,6 +37,9 @@ set(CXX_TEST_TARGETS_CERES
   # SE23
   gtest_se23_ceres
 
+  # SGal3
+  gtest_sgal3_ceres
+
   # Bundle
   gtest_bundle_ceres
 )
diff --git a/test/ceres/gtest_sgal3_ceres.cpp b/test/ceres/gtest_sgal3_ceres.cpp
new file mode 100644
index 00000000..15e66071
--- /dev/null
+++ b/test/ceres/gtest_sgal3_ceres.cpp
@@ -0,0 +1,10 @@
+#include "manif/SGal3.h"
+#include "ceres_test_utils.h"
+
+#include <ceres/ceres.h>
+
+using namespace manif;
+
+MANIF_TEST_JACOBIANS_CERES(SGal3d);
+
+MANIF_RUN_ALL_TEST;
diff --git a/test/python/test_manif.py b/test/python/test_manif.py
index 00844051..b02d5dbf 100644
--- a/test/python/test_manif.py
+++ b/test/python/test_manif.py
@@ -1,22 +1,37 @@
-from manifpy import \
-    R1, R1Tangent, \
-    R2, R2Tangent, \
-    R3, R3Tangent, \
-    R4, R4Tangent, \
-    R5, R5Tangent, \
-    R6, R6Tangent, \
-    R7, R7Tangent, \
-    R8, R8Tangent, \
-    R9, R9Tangent, \
-    SE2, SE2Tangent, \
-    SE3, SE3Tangent, \
-    SE_2_3, SE_2_3Tangent, \
-    SO2, SO2Tangent, \
-    SO3, SO3Tangent
-
 import numpy as np
-
 import pytest
+from manifpy import (
+    R1,
+    R2,
+    R3,
+    R4,
+    R5,
+    R6,
+    R7,
+    R8,
+    R9,
+    SE2,
+    SE3,
+    SE_2_3,
+    SO2,
+    SO3,
+    R1Tangent,
+    R2Tangent,
+    R3Tangent,
+    R4Tangent,
+    R5Tangent,
+    R6Tangent,
+    R7Tangent,
+    R8Tangent,
+    R9Tangent,
+    SE2Tangent,
+    SE3Tangent,
+    SE_2_3Tangent,
+    SGal3,
+    SGal3Tangent,
+    SO2Tangent,
+    SO3Tangent,
+)
 
 
 @pytest.mark.parametrize(
@@ -36,6 +51,7 @@
      (SE_2_3, SE_2_3Tangent),
      (SO2, SO2Tangent),
      (SO3, SO3Tangent),
+     (SGal3, SGal3Tangent),
     ]
 )
 class TestCommon:
diff --git a/test/python/test_sgal3.py b/test/python/test_sgal3.py
new file mode 100644
index 00000000..3cf24e6d
--- /dev/null
+++ b/test/python/test_sgal3.py
@@ -0,0 +1,81 @@
+import numpy as np
+import pytest
+from manifpy import SGal3, SGal3Tangent
+
+
+def test_constructor():
+    state = SGal3(0,0,0, 0,0,0, 0,0,0, 0)
+    assert 0 == state.x()
+    assert 0 == state.y()
+    assert 0 == state.z()
+    # assert 0 == state.quat()
+    assert 0 == state.vx()
+    assert 0 == state.vy()
+    assert 0 == state.vz()
+
+    # state = SE_2_3(np.array([1,2,3]), Quaternion(1,0,0,0), np.array([4,5,6]))
+    # assert 1 == state.x()
+    # assert 2 == state.y()
+    # assert 3 == state.z()
+    # assert 1 == state.quat()
+    # assert 4 == state.vx()
+    # assert 5 == state.vy()
+    # assert 6 == state.vz()
+
+    # state = SE_2_3(np.array([1,2,3]), AngleAxis(0, UnitX()), np.array([4,5,6]))
+    # assert 1 == state.x()
+    # assert 2 == state.y()
+    # assert 3 == state.z()
+    # assert 1 == state.w()
+    # assert 4 == state.vx()
+    # assert 5 == state.vy()
+    # assert 6 == state.vz()
+
+    # delta = SE_2_3Tangent(1,2,3)
+    # assert 1 == delta.x()
+    # assert 2 == delta.y()
+    # assert 3 == delta.z()
+
+def test_accessors():
+    state = SGal3.Identity()
+    assert 0 == state.x()
+    assert 0 == state.y()
+    assert 0 == state.z()
+    # assert 0 == state.quat()
+    assert 0 == state.vx()
+    assert 0 == state.vy()
+    assert 0 == state.vz()
+
+    delta = SGal3Tangent.Zero()
+
+    # assert 0 == delta.x()
+    # assert 0 == delta.y()
+    # assert 0 == delta.z()
+
+# def test_isometry():
+#     state = SE_2_3.Identity()
+#     isometry = state.isometry()
+#
+#     assert (4, 4) == isometry.shape
+#     assert (np.identity(4) == isometry).all()
+
+def test_rotation():
+    state = SGal3.Identity()
+    rotation = state.rotation()
+
+    assert (3, 3) == rotation.shape
+    assert (np.identity(3) == rotation).all()
+
+# def test_quaternion():
+#     state = SO3.Identity()
+#     quaternion = state.quaternion()
+#
+#     assert (4,) == quaternion.shape
+#     assert (np.zeros(4,) == quaternion).all()
+
+def test_translation():
+    state = SGal3.Identity()
+    translation = state.translation()
+
+    assert (3,) == translation.shape
+    assert (np.zeros(3,) == translation).all()
diff --git a/test/sgal3/CMakeLists.txt b/test/sgal3/CMakeLists.txt
new file mode 100644
index 00000000..9c9f7d92
--- /dev/null
+++ b/test/sgal3/CMakeLists.txt
@@ -0,0 +1,13 @@
+# SGal3 tests
+
+manif_add_gtest(gtest_sgal3 gtest_sgal3.cpp)
+
+set(CXX_TEST_TARGETS
+
+  ${CXX_TEST_TARGETS}
+
+  # SGal3
+  gtest_sgal3
+
+  PARENT_SCOPE
+)
diff --git a/test/sgal3/gtest_sgal3.cpp b/test/sgal3/gtest_sgal3.cpp
new file mode 100644
index 00000000..a37374bc
--- /dev/null
+++ b/test/sgal3/gtest_sgal3.cpp
@@ -0,0 +1,362 @@
+#include <gtest/gtest.h>
+
+#include "manif/SGal3.h"
+#include "../common_tester.h"
+
+#include <Eigen/Geometry>
+#include <iostream>
+using namespace manif;
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_DATATYPE) {
+  SGal3d::DataType values; values << 0,0,0, 0,0,0,1, 0,0,0, 0;
+  SGal3d sgal3(values);
+
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(10));
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_T_Q_V) {
+  SGal3d sgal3(
+    SGal3d::Translation(1,2,3),
+    Eigen::Quaterniond::Identity(),
+    SGal3d::LinearVelocity(4, 5, 6),
+    1
+  );
+
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(4, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(5, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(6, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(10));
+
+  EXPECT_EIGEN_NEAR(Eigen::Vector3d(1, 2, 3), sgal3.translation());
+  EXPECT_EIGEN_NEAR(Eigen::Quaterniond::Identity().coeffs(), sgal3.quat().coeffs());
+  EXPECT_EIGEN_NEAR(Eigen::Vector3d(4, 5, 6), sgal3.linearVelocity());
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_T_AA_V) {
+  SGal3d sgal3(
+    SGal3d::Translation(1,2,3),
+    Eigen::AngleAxis<double>(Eigen::Quaterniond::Identity()),
+    SGal3d::LinearVelocity(1, 2, 3),
+    1
+  );
+
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(10));
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_ISOMETRY) {
+  Eigen::Isometry3d h = Eigen::Translation3d(1,2,3) * Eigen::Quaterniond::Identity();
+  SGal3d sgal3(h, Eigen::Vector3d(1, 2, 3), 1);
+
+  Eigen::Matrix<double, 5, 5> hse23 = Eigen::Matrix<double, 5, 5>::Identity();
+  hse23.topLeftCorner<4, 4>() = h.matrix();
+  hse23.topRightCorner<3, 1>() = Eigen::Vector3d(1, 2, 3);
+  hse23(3, 4) = 1;
+
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(10));
+  EXPECT_EIGEN_NEAR(hse23, sgal3.isometry());
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_COPY) {
+  SGal3d::DataType values; values << 3,2,1, 0,0,0,1, 1,2,3, 4;
+  SGal3d o(values);
+  SGal3d sgal3(o);
+
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(2, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(3, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(4, sgal3.coeffs()(10));
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_DATA) {
+  SGal3d::DataType values; values << 3,2,1, 0,0,0,1, 1,2,3, 4;
+  SGal3d sgal3(values);
+
+  double * data_ptr = sgal3.data();
+
+  ASSERT_NE(nullptr, data_ptr);
+
+  EXPECT_DOUBLE_EQ(3, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(2, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(1, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(0, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(0, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(0, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(1, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(1, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(2, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(3, *data_ptr);
+  ++data_ptr;
+  EXPECT_DOUBLE_EQ(4, *data_ptr);
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_CAST) {
+  SGal3d sgal3d(
+    SGal3d::Translation(1,2,3),
+    Eigen::Quaterniond::Identity(),
+    SGal3d::LinearVelocity(1,2,3),
+    1
+  );
+
+  EXPECT_DOUBLE_EQ(1, sgal3d.coeffs()(0));
+  EXPECT_DOUBLE_EQ(2, sgal3d.coeffs()(1));
+  EXPECT_DOUBLE_EQ(3, sgal3d.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3d.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3d.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3d.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3d.coeffs()(6));
+  EXPECT_DOUBLE_EQ(1, sgal3d.coeffs()(7));
+  EXPECT_DOUBLE_EQ(2, sgal3d.coeffs()(8));
+  EXPECT_DOUBLE_EQ(3, sgal3d.coeffs()(9));
+  EXPECT_DOUBLE_EQ(1, sgal3d.coeffs()(10));
+
+  SGal3f sgal3f = sgal3d.cast<float>();
+
+  EXPECT_DOUBLE_EQ(1, sgal3f.coeffs()(0));
+  EXPECT_DOUBLE_EQ(2, sgal3f.coeffs()(1));
+  EXPECT_DOUBLE_EQ(3, sgal3f.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3f.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3f.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3f.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3f.coeffs()(6));
+  EXPECT_DOUBLE_EQ(1, sgal3f.coeffs()(7));
+  EXPECT_DOUBLE_EQ(2, sgal3f.coeffs()(8));
+  EXPECT_DOUBLE_EQ(3, sgal3f.coeffs()(9));
+  EXPECT_DOUBLE_EQ(1, sgal3f.coeffs()(10));
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_IDENTITY) {
+  SGal3d sgal3;
+
+  sgal3.setIdentity();
+
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(10));
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_IDENTITY2) {
+  SGal3d sgal3 = SGal3d::Identity();
+
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(0));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(1));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3.coeffs()(6));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(7));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(8));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(9));
+  EXPECT_DOUBLE_EQ(0, sgal3.coeffs()(10));
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_RANDOM) {
+ SGal3d sgal3;
+
+ sgal3.setRandom();
+
+ const auto q_norm = sgal3.coeffs().segment<4>(3).norm();
+
+ EXPECT_DOUBLE_EQ(1, q_norm);
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_RANDOM2) {
+ const SGal3d sgal3 = SGal3d::Random();
+
+ const auto q_norm = sgal3.coeffs().segment<4>(3).norm();
+
+ EXPECT_DOUBLE_EQ(1, q_norm);
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_INVERSE) {
+  SGal3d sgal3 = SGal3d::Identity();
+
+  auto sgal3_inv = sgal3.inverse();
+
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(0));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(1));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3_inv.coeffs()(6));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(7));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(8));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(9));
+  EXPECT_DOUBLE_EQ(0, sgal3_inv.coeffs()(10));
+
+  sgal3 = SGal3d::Random();
+
+  EXPECT_MANIF_NEAR(SGal3d::Identity(), sgal3.inverse()*sgal3);
+  EXPECT_MANIF_NEAR(SGal3d::Identity(), sgal3*sgal3.inverse());
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_COMPOSE_IDENTITY) {
+  SGal3d sgal3a = SGal3d::Identity();
+  SGal3d sgal3b = SGal3d::Identity();
+
+  auto sgal3c = sgal3a.compose(sgal3b);
+
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(0));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(1));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(2));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(3));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(4));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(5));
+  EXPECT_DOUBLE_EQ(1, sgal3c.coeffs()(6));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(7));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(8));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(9));
+  EXPECT_DOUBLE_EQ(0, sgal3c.coeffs()(10));
+
+  sgal3a = SGal3d::Random();
+  sgal3c = sgal3a.compose(sgal3b);
+
+  EXPECT_MANIF_NEAR(sgal3a, sgal3c);
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_LOG_EXP) {
+  SGal3d sgal3 = SGal3d::Random();
+
+  EXPECT_MANIF_NEAR(sgal3, sgal3.log().exp());
+}
+
+// TEST(TEST_SGAL3, TEST_SGAL3_ACT)
+// {
+//   SGal3d sgal3 = SGal3d::Identity();
+
+//   auto transformed_point = sgal3.act(Eigen::Vector3d(1,1,1));
+
+//   EXPECT_NEAR(+1, transformed_point.x(), 1e-15);
+//   EXPECT_NEAR(+1, transformed_point.y(), 1e-15);
+//   EXPECT_NEAR(+1, transformed_point.z(), 1e-15);
+
+//   sgal3 = SGal3d(1,1,1,MANIF_PI,MANIF_PI_2,MANIF_PI/4.,0,0,0);
+
+//   transformed_point = sgal3.act(Eigen::Vector3d(1,1,1));
+
+//   EXPECT_NEAR( 1, transformed_point.x(), 1e-15);
+//   EXPECT_NEAR(-0.414213562373, transformed_point.y(), 1e-12);
+//   EXPECT_NEAR( 0, transformed_point.z(), 1e-15);
+
+//   // to demonstrate that the velocity terms do not affect the rigid motion action
+//   sgal3 = SGal3d(-1,-1,-1,MANIF_PI/4,-MANIF_PI_2,-MANIF_PI,0,0,1);
+
+//   transformed_point = sgal3.act(Eigen::Vector3d(1,1,1));
+
+//   EXPECT_NEAR( 0.414213562373, transformed_point.x(), 1e-12);
+//   EXPECT_NEAR(-1, transformed_point.y(), 1e-15);
+//   EXPECT_NEAR( 0, transformed_point.z(), 1e-15);
+// }
+
+TEST(TEST_SGAL3, TEST_SGAL3TAN_LINANGVELACC) {
+  SGal3Tangentd::DataType data;
+  data << 1,2,3, 4,5,6, 7,8,9, 10;
+  SGal3Tangentd se23tan(data);
+
+  EXPECT_EIGEN_NEAR(Eigen::Vector3d(1, 2, 3), se23tan.lin());
+  EXPECT_EIGEN_NEAR(Eigen::Vector3d(4, 5, 6), se23tan.lin2());
+  EXPECT_EIGEN_NEAR(Eigen::Vector3d(7, 8, 9), se23tan.ang());
+  EXPECT_DOUBLE_EQ(10, se23tan.t());
+}
+
+#ifndef MANIF_NO_DEBUG
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_NOT_NORMALIZED_ARGS) {
+  SGal3d::DataType values; values << 0,0,0, 1,1,1,1, 0,0,0, 0;
+
+  EXPECT_THROW(SGal3d sgal3(values), manif::invalid_argument);
+
+  try {
+    SGal3d sgal3(values);
+  } catch (manif::invalid_argument& e) {
+    EXPECT_FALSE(std::string(e.what()).empty());
+  }
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_CONSTRUCTOR_UNNORMALIZED) {
+  EXPECT_THROW(SGal3d(SGal3d::DataType::Random()*10.), manif::invalid_argument);
+}
+
+TEST(TEST_SGAL3, TEST_SGAL3_NORMALIZE) {
+  using DataType = SGal3d::DataType;
+  DataType data = DataType::Random() * 100.;
+
+  EXPECT_THROW(SGal3d a(data), manif::invalid_argument);
+
+  Eigen::Map<SGal3d> map(data.data());
+  map.normalize();
+
+  EXPECT_NO_THROW(SGal3d b = map);
+}
+
+#endif
+
+MANIF_TEST(SGal3d);
+
+MANIF_TEST_MAP(SGal3d);
+
+MANIF_TEST_JACOBIANS(SGal3d);
+
+MANIF_RUN_ALL_TEST;