Models of a hybrid wheeled hopping self-balanced robot

Abstract

Combining wheeled structure with hopping mechanism, this paper purposes a self-balanced hopping robot with hybrid motion pattern. The main actuator which is the cylindrical cam, optimized by particle swarm optimization (PSO), is equipped with the motor to control the hopping motion. Robotic system dynamics model is established and solved by Lagrangian method. After linearization, control characteristics of the system is obtained by classical control theory based on dynamics equations. By applying Adams and Matlab to simulate the system, hopping locomotion and self-balanced capability are validated respectively, and result shows that jump height can reach 750 mm theoretically. Then PID control scheme is developed and specific models of hardware and software are settled down accordingly. Finally, prototype is implemented and series of hopping experiments are conducted, showing that with different projectile angle, prototype can jump 550 mm in height and 460 mm in length, transcending majority of other existing hopping robots.

Study on the effect of curvature radius sudden change on mechanism characteristics for the constant-breadth two circular-arc cam mechanism with an inclined flat-faced follower

“…Bezier curve was employed by Li to redesign the cam profile, aiming at a lower torque fluctuation of the cam mechanism. 34 Bezier curves of degrees 5, 7, and 9 were used by Acevedo, to design a cam for seeking the practical use of Von Mises in a cam mechanism. 35 According to the known prior art, the studies about using non-uniform input motions as cam’s input are rarely about multi-objective optimization functions.…”