Analysis of high acceleration shock pulses part I: Geometry of incident mass

This is the first of two papers that deal with the examination of high acceleration pulses produced by a velocity amplification machine, capable of exciting micro-scale devices. The machine is based on the principle of using multiple sequential impacts to amplify velocity through a system of progressively smaller masses constrained to move in the vertical axis. In this paper, high acceleration pulses are created through the metal-on-metal impact between the penultimate and ultimate masses and the companion paper Il looks specifically at the acceleration pulses created using a range of interface impact materials. The machine has been shown to generate pulses in excess of 70,00g for an impact velocity of approximately 4.2m/s. Modifications to the machine were realised in order to obtain high acceleration pulses of controlled amplitude and duration. Analytical and FE analyses were conducted, with the ultimate incident mass modelled as a solid insert, isolated from any complex geometry by a carrier of compliant material. The analyses contributed to the design of the ultimate mass of a velocity amplification machine, and an extensive experimental investigation was carried out to obtain results for high acceleration impact. The primary outcome of the research is a design for the penultimate and ultimate masses of a velocity amplifier in order to achieve high acceleration pulses of controlled amplitude and duration.