Two novel approaches for solving the contradiction between efficient penetration and low recoil for the low‐velocity penetrator

Abstract

The low‐velocity penetrator (LVP) is a planetary penetration device that can drive itself to a target depth through its internal periodic impacts. When LVP generates impact energy, it inevitably produces a recoil that can only be counteracted by friction with the soil, if there is no other auxiliary device. Unfortunately, LVP is extraordinarily sensitive to the recoil during the initial stage since the small contact area with the soil results in minor friction between them. Significantly, once the recoil exceeds the friction, LVP cannot work properly and may even retreat, inducing mission failure. In this paper, we develop an optimized LVP with an auxiliary device for lower recoil and higher performance. Specifically, we establish a dynamic model to analyze the single‐cycle motion of LVP and provide essential support for its optimization and design. Meanwhile, an integration method is proposed to calculate the friction between LVP and the soil reasonably and accurately. On the basis of these, we obtain the optimal mass and stiffness parameters of LVP that meet both high penetration efficiency and low recoil. Furthermore, only relying on the parameter optimization is insufficient to eliminate the recoil, and an auxiliary penetration scheme is proposed to provide an external force counteracting the recoil until LVP arrives at a certain depth. Through multiple comparative penetration experiments, we validate the effectiveness of our approaches in promoting penetration ability, stability, and restraining the recoil of LVP. This work provides two novel approaches for solving the contradiction of efficient penetration while reducing the recoil for LVP.