Equal-strength beam design of acoustic wave accelerometers

Surface acoustic wave (SAW) based accelerometers have received significant attention due to their digital output, low cost, mass production and easy implementation of wireless passive function. However, conventionally rectangular cantilever-beam based SAW accelerometers often have non-uniform strains generated along the beams, which cause emergence of parasitic wave modes and measurement errors. In this paper, a simulation platform was developed to analyze and optimize designs of SAW accelerometers and variable-thickness and equal-strength beams were designed to solve the critical issue of non-uniform strain distribution along the beam. Frequency responses of SAW accelerometers under the acceleration were successfully obtained using the simulation platform, with the visualized strain/stress distribution and particle displacement field. The accuracy of this simulation platform was verified using the experimental result reported in literature. A highly sensitive and equal-strength beam SAW accelerometer was achieved with a sensitivity up to 1.40 kHz g-1, a linearity coefficient of similar to 1, and a measurement range of 0 similar to 15 g. Furthermore, a high-G accelerometer was designed, with the capability of enduring large shocks up to 11,500 g and a sensitivity of 6.96 Hz g-1.

Automated summary

In this paper, a simulation platform was developed to analyze and optimize designs of SAW accelerometers. Variable-thickness and equal-strength beams were designed to solve the issue of non-uniform strain distribution. Frequency responses of SAW accelerometers were successfully obtained using the simulation platform, and its accuracy was verified through experiments. Highly sensitive and equal-strength beam SAW accelerometer, as well as a high-G accelerometer, were achieved.