Planar Motion Control of a Quadruped Robot

In robotics, the ability of quadruped robots to perform tasks in industrial, mining, and disaster environments has already been demonstrated. However, to move a robot in different environments, it is necessary to properly plan the steps and control its legs. This article considers a quadruped robot with legs modeled using the Euler–Lagrange equations. The robot’s control strategy uses impedance control for each leg with reference trajectories generated by sixth-degree Bézier curves, which are constructed based on leg velocities through a planar kinematic model. Then, a body control scheme commands the robot to follow a predefined trajectory. The proposed control strategy is implemented in Matlab and simulated in CoopeliaSim using the Vortex physics engine. The simulations successfully illustrate the control strategy that commands the robot to follow a reference trajectory with static walking and trotting gait patterns.