Trajectory Generation for Tip-Over Prevention and Collision Avoidance of Automatic Excavators

This paper proposes a method for generating end-effector trajectories for automatic excavators to prevent tipping over and avoid collisions with obstacles. The criterion for determining whether the excavator is at risk of tipping over is derived using the Zero-Moment Point (ZMP), which represents the center of reaction forces. A simplified model of the excavator is used in this derivation to avoid complexity. Additionally, the end-effector trajectories are automatically generated by using an algorithm based on the penalty function method, which incorporates constraints to prevent both tipping over and collisions with nearby obstacles. The automated excavator followed the generated trajectories in a simulator, and it was confirmed that tipping over was prevented and collisions with obstacles were avoided.