Design of LQR controller for Ballbot and hardware implementation

Abstract

A Ballbot is a single spherical wheeled robot with single point of contact with ground. This makes the system statically unstable. It attains stability only with the help of a sophisticated controller. For the controller design and to analyze the behavior of the system, the ballbot was modelled using Lagrangian formulation and a state-space model is derived. LQR controllers for each plane of instability are designed and then tuned from simulation results and was implemented on hardware. The controller is implemented as a computer algorithm that reads/senses various physical parameters of the robot and generates a computed control signal. Ballbot structure is designed using Solidworks software and the hardware model is fabricated. The system.