A micro-piezoelectric inertial robot with an ultra-high load-to-weight ratio: design and experimental evaluation

Abstract

Abstract Small robots are anticipated to be employed for inspection tasks in small spaces, such as pipelines and cavities in aircraft and satellites. Nevertheless, their low load capacity constitutes an obvious disadvantage that is often hard to overcome, impeding the utilization of such robots. This study introduces a micro-piezoelectric inertial robot (MPIR) that exhibits an ultra-high load-to-weight ratio, which exceeds that of all previously reported piezo-driven robots in the relevant literature. The developed prototype MPIR, measuring 46 × 50 × 13.5 mm 3 and weighing 32.45 g, was designed through structural optimization and dynamic analysis. It achieves in-plane translational and rotational motions using two piezoelectric driving units. The test results demonstrated that our robot achieved a linear velocity of approximately 1.3 mm s −1 and a rotation velocity of around 19 mrad s −1 under a load-to-weight ratio (ratio between the mass of the load and the mass of the robot) of 140.09 by applying a driving voltage of 100 V p–p and a frequency of 100 Hz. The simulation results of the dynamic model predicted a maximum load-to-weight ratio of 260. The remarkable load-bearing capacity, simple structure, and immunity to electromagnetic interference render MPIR suitable for specific spatial tasks, such as localized firefighting and structural repair in space stations, especially in confined spaces.