Road Runner Advanced Examples

You should be fairly familiar with Road Runner and the quickstart before taking a look at these samples.

The main quickstart repo can be found here.

Installation

For more detailed instructions on getting Road Runner setup in your own project, see the Road Runner README.

1. Download or clone this repo with git clone https://github.com/acmerobotics/road-runner-quickstart.

2. Open the project in Android Studio and build TeamCode like any other ftc_app project.

Samples:

1. Passing pose data between opmodes

   Files:

   • teamcode/drive/advanced/TeleOpJustLocalizer.java

   • teamcode/drive/advanced/AutoTransferPose.java

   • teamcode/drive/advanced/PoseStorage.java

   If you wish to read your localizer's pose during teleop, you need to know where your initial pose is. If an initial pose is not set, the program will assume you start at x: 0, y: 0, and heading: 0, which is most likely not what you want. So, to know where you are teleop, you must know where you ended in auto. This sample explains how to do so via a static class, PoseStorage, that allows data to persist between opmodes. AutoTransferPose will write its pose estimate to PoseStorage.currentPose. Because this is a static field, it will persist between opmodes. Thus, a teleop afterwards is able to read from it and know where the autonomous opmode ended.

2. Road Runner in teleop - just the localizer

   File:

   • teamcode/drive/advanced/TeleOpJustLocalizer.java

   Example code demonstrating how one would read from their localizer in teleop. Utilizes a static class to pass data between opmodes. This sample reads from the PoseStorage static field to set an initial starting pose. An autonomous opmode should have written its last known pose to the PoseStorage.currentPose field.

3. Road Runner in teleop - incorporating the drive class

   File:

   • teamcode/drive/advanced/TeleOpDrive.java

   Example code demonstrating how one would incorporate the SampleMecanumDrive class into their teleop, without the need for a separate robot class. Instead, this sample utilizes the drive class's kinematics and setDrivePower() function. This sample is essentially just a modified LocalizationTest.java with pose extraction from PoseStorage and additional comments.

4. Road Runner in teleop - field centric drive

   File:

   • teamcode/drive/advanced/TeleOpFieldCentric.java

   Example code demonstrating how one would implement field centric control using SampleMecanumDrive.java. This file is essentially just TeleOpDrive.java with the addition of field centric control. To achieve field centric control, the only modification one needs is to rotate the input vector by the current heading before passing it into the inverse kinematics.

5. Road Runner in teleop - align to point

   File:

   • teamcode/drive/advanced/TeleOpAlignWithPoint.java

   Example code demonstrating how to align the bot to a specified point in teleop. The user is able to switch from normal driver control mode to alignment mode. Alignment mode will switch into field centric and independently control heading via a PID controller to align with the specified point.

6. Async following with FSM orchestration

   File:

   • teamcode/drive/advanced/AsyncFollowingFSM.java

   Example opmode describing how one utilizes async following in conjunction with finite state machines to orchestrate variable, multi-step movements. This allows for complex autonomous programs.

7. Breaking from a live trajectory

   Files:

   • teamcode/drive/advanced/AutoBreakTrajectory.java
   • teamcode/drive/advanced/SampleMecanumDriveCancelable.java

   Example opmode describing how to break out from a live trajectory at any arbitrary point in time. This allows for neat things like incorporating live trajectory following in your teleop. TeleOpAugmentedDriving.java will build on this concept. This opmode will prematurely stop the following 3 seconds into starting it.

   This opmode utilizes the SampleMecanumDriveCancelable.java class. The default SampleMecanumDrive.java class does not allow for arbitrary following cancellation.

8. Automatic driving in teleop

   Files:

   • teamcode/drive/advanced/TeleOpAugmentedDriving.java
   • teamcode/drive/advanced/SampleMecanumDriveCancelable.java

   WARNING: THIS IS A DEMONSTRATION OF ROAD RUNNER'S CAPABILITIES. I DO NOT RECOMMEND DOING THIS IN GAME

   Example opmode demonstrates how one can augment driver control by following arbitrary Road Runner trajectories at any time during teleop. This really isn't recommended at all. This is not what Trajectories are meant for. A path follower is more suited for this scenario. This sample primarily serves as a demo showcasing Road Runner's capabilities.

   See the comments for details on the driver augmentation.