Towards a Wireless Force Sensor Based on Wave Backscattering for Medical Applications

In medical applications, sensing forces along surgical tools is of high importance in order to avoid collateral damage of tissue and surrounding structures. However, the space available in their central lumen limits the routing of wired sensors that are widely available today, and thus their integration into such tools. In this paper, we present a new wireless force sensor based on wave backscattering that reflects electromagnetic waves with phase changes that are directly related to the applied force magnitude and location. The proposed sensor can sense force magnitudes with an average error of 0.01 N and a standard deviation of 0.49 N, and their application location with an average error of -0.33 mm and a standard deviation of 0.82 mm. The sensor also has the potential to be translated to applications beyond medical instruments, including applications involving a large number of sensors and situations where wire routing is challenging due to the environment in which they are used.