Development of a One-Legged Piezoelectric Robot with Agile Motion, High-Speed, and Large-Load Capabilities

A novel two-degree-of-freedom ultrasonic piezoelectric robot (UPR) imitating skateboard configuration is proposed to address the balance among simplification, load capacity, and velocity. A single piezo leg based on longitudinal-bending-bending composition (LBBC) was designed to generate multidimensional actuation trajectories. Adjusting the plane of terminal trajectories can actively generate or eliminate static friction along the rotary axis of wheels, which helps UPR achieve agile linear and rotational motions. Besides, the skateboard configuration cooperating with the longitudinal vibration leg lift scheme could balance the load capacity and velocity. A prototype with a size of 56 × 55 × 51 mm3 was assembled, and its performances were tested. Experiments prove that the robot can achieve both linear and rotary motions with only one piezo leg. It can reach high velocities of 617.11 mm/s (∼11 BL/s) and 10.70 rad/s. Under a load of 300 g (3.26 times its weight), it still can maintain velocities of 440.13 mm/s (7.85 BL/s) and 10.46 rad/s, verifying a good balance between load capacity and velocity. The robot obtains a maximum resolution of 0.09 μm utilizing the front-kicking gait. The proposed UPR exhibits great potential in efficient wide-area micromanipulation.