Event-based control system on FPGA applied to the pencil balancer robotic platform

Abstract

An event-based motor controller design is presented. The system is designed to solve the classic inverted pendulum problem by using a robotic platform and a totally neuro-inspired event-based mechanism. Specifically, DVS retinas provide feedback and an FPGA implements control. The robotic platform used is the so called ’pencil balancer’. The retinas provide visual information to the FPGA that processes it and obtains the center of mass of the pencil. Once this center of mass is averaged over time, it is used joint with the cart position provided by a flat potentiometer bar to compute the angle of the pencil from the vertical. The angle is delivered to an eventbased Proportional-Derivative (PD) controller that drives the DC motor using Pulse Frequency Modulation (PFM) to accomplish the control objective. The results show an accurate, real-time and efficient controller design.