Design of impact ultrasonic penetrator and optimization of impact efficiency

This paper proposes, optimizes, and experimentally investigates a thread-clamped ultrasonic penetrator that uses a spring to induce forced vibration in the transducer, thereby enhancing drilling efficiency. The penetrator consists mainly of a transducer, a free mass, an elastic energy storage unit, a drilling tool, and a housing. The elastic energy storage unit is attached to the transducer's flange, permitting limited axial movement. When excited by a sinusoidal signal at a specific frequency, the transducer's front end generates high-frequency longitudinal vibrations that impact the free mass. Upon colliding with the drilling tool and the transducer subsequently, the elastic energy storage unit absorbs and utilizes this energy, optimizing the energy transfer process. This study designs the penetrator's structure, analyzes the motion curves of each component, and derives the kinetic energy curve of the drilling tool. A novel particle swarm optimization algorithm is employed to optimize the key parameters of the penetrator, verifying the optimization effect. The prototype was fabricated, and its vibration and output characteristics were tested. The results from rigorous testing clearly demonstrate a significant improvement in the penetrator's drilling efficiency after meticulous structural and parameter optimization. Both simulation and experimental results confirm the feasibility of the penetrator.