Controlling robot dynamics via environmental deformations

In an effort to construct a robophysical analog gravity system, we previously studied the dynamics of a 200-gram differential wheeled robot driving on a deformable spandex membrane (d=2.4m) with a static central depression (Li et al., 2019). The system displays rich dynamics, including precessing orbits reminiscent of those in general relativity. Remarkably, the vehicle-membrane system can be mapped to the dynamics of a test particle in a fiducial spacetime. To take the next step and study how the vehicle dynamics can be manipulated via dynamic non-local changes in membrane curvature, we developed an automated gantry system that can control the position of a spherical object which creates a local deformation on the membrane. From experiments implementing a closed, circular object trajectory, the translating depression can capture the locomoting car from specific initial conditions, depending on initial orientation and position of the car and object trajectories. We explore how feedback from internally based measurements of the vehicle’s tilt and acceleration can enhance capture rates.