Mechatronic Design and Control of an Underactuated Three-link Brachiation Robot

Brachiation is a way of moving from place to place by swinging between branches of trees, employed by monkeys (mostly gibbons), using only their arms. During brachiation, if the next branch is far away such that the gibbon is expected to have a dynamic free flight phase in its motion, this fast motion mode is called ’Fast Brachiation’ or ’Ricochetal Brachiation’. A lot of research has been conducted in the area of implementing this type of brachiation in robots to enable surveillance capabilities in agricultural fields, animal mimicking, deep forest searches, etc. During this master’s thesis, the aim is to design and implement control in a simplified underactuated 3-link robot, that is capable of performing Fast Brachiation. A passive tail in the robot helps it achieve optimal swing velocity to ricochet between distant support bars. The robot will comprise three links (two arms and one passive tail) and two actuators with unactuated grippers. The robot will be expected to brachiate through a horizontal ladder with equally spaced support bars. Given that the robot is underactuated and that its motion is discontinuous poses a challenge that we aim to overcome. As a part of this master’s thesis, would be the optimal design and mechatronic integration of the robot, generation of optimal trajectory, and a model-based trajectory stabilization. The contribution to the community of this master’s thesis would be to achieve both Slow and Fast Brachiation using passive grippers on a 3-link underactuated robot.