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README.md

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 ## 1. Overview
 
-This repository contains implementation codes of robotic [***rock-and-walk*** **manipulation**](https://youtu.be/yyURupLXQjk) for dynamic and non-prehensile object transport. The object, which is in contact with an environmental surface, is basically manipulated to rock from side to side about the contact point iteratively by the robot system. In the meantime, the passive dynamics due to gravity enables the object to roll along a zigzag path that leads to a forward walk. Rock-and-walk is a special-purpose method that enables the transport of a certain class of objects, which are too large and heavy to apply other primary methods such as grasping- or pushing-based operations. Our work is motivated by an interesting question in archaeology, how the giant rock statues of Easter Island (known as “moai”) were transported several hundred years ago, and a recent [demonstration](https://www.youtube.com/watch?v=J5YR0uqPAI8&ab_channel=NationalGeographic) performed by archaeologists that it is possible to walk the statue by iterative rocking. 
+This repository contains implementation codes of robotic ***rock-and-walk*** manipulation ([**video**](https://youtu.be/yyURupLXQjk)) for dynamic and non-prehensile object transport. The object, which is in contact with an environmental surface, is basically manipulated to rock from side to side about the contact point iteratively by the robot system. In the meantime, the passive dynamics due to gravity enables the object to roll along a zigzag path that leads to a forward walk. Rock-and-walk is a special-purpose method that enables the transport of a certain class of objects, which are too large and heavy to apply other primary methods such as grasping- or pushing-based operations. Our work is motivated by an interesting question in archaeology, how the giant rock statues of Easter Island (known as “moai”) were transported several hundred years ago, and a recent [demonstration](https://www.youtube.com/watch?v=J5YR0uqPAI8&ab_channel=NationalGeographic) performed by archaeologists that it is possible to walk the statue by iterative rocking. 
 
 Our implementation employs a feedback control strategy for sustainable rock-and-walk gaiting through the effective regulation of the object’s energy and posture in multiple robotic settings: **caging-based single-arm manipulation**, **cable-driven dual-arm manipulation**, and **aerial manipulation**.