Cassie Blue is operating with our normal flat-ground feedback controller. We made no changes to accommodate the sand. We were quite surprised that she could walk barefoot in such soft sand! Our best guess is that this ability is a fortunate outcome of the way we control her "feet". When a leg is in the air, we control the corresponding foot to be level with the ground. When a leg is in contact with the ground, we set the "ankle" torque to zero. In other words, we are treating the robot as being underactuated.
The Discovery Channel was filming on May 9, 2018.
Cassie Blue is walking with control laws developed at Michigan in this publication: Da, X., Harib, O., Hartley, R., Griffin, B., & Grizzle, J. W. (2016). From 2D design of underactuated bipedal gaits to 3D implementation: Walking with speed tracking. IEEE Access, 4, 3469-3478.
Cassie was built by Agility Robotics. The robot's purchase was enabled by funding from NSF Inspire Grant ECCS-1343720 and Toyota Research Institute (TRI). The work on the control law was funded by NSF Grant NRI-1525006.
Социальные закладки