Test Objects for Performing Capacitive Sensing Benchmark Tests in Human Robot Collaborative Scenarios

Supplementary Data for Publication A Safety Benchmark for Capacitive Proximity Sensing Robotic Skins - Safe Transient Contact in Compliance to ISO TS 15066: Power and Force Limiting (PFL) Disclaimer: This publication was submitted and is currently under review to be published for IEEE RA-L with ICRA 2021 option. Fundings: The research leading to this results has received fundingfrom the ”Kärntner Wirtschaftsförderung Fonds” (KWF) and the ”European Regional Development Fund” (EFRE) within the CapSize project 26616/30969/44253 Preliminary version of the abstract: During co-presence of human workers and robotsin the same workspace, Power and Force Limiting (PFL)according to ISO TS 15066 is required to avoid injuries duringundesired contacts. Capacitive Proximity Sensors (CPSs) offer acost-effective solution to cover the entire robot manipulator withfast close-range perception for Human Robot Collaboration(HRC) tasks.Compared to pure tactile or force sensing, the sensors allowan increase of operating speeds of cobots while still maintainingPFL. The robot reacts before impacts occur and does not sufferfrom occlusion, as the sensors close the perception gap left bytactile detection and mid range distance sensors. However, sincecapacitive coupling to obstacles varies not only with distance,but also with shape and material properties, the projectionfrom capacitance to actual distances is a general problem. Areference benchmark is required for the evaluation to ensuresafe PFL.We derive the requirements described in ISO TS 15066for PFL of critical body regions and propose a method fordetermining the pre-detection operation speed to comply withPFL. Researchers from four different institutes present threedifferent designs of capacitive sensors and their applicabilityon different robots. We propose a universal benchmark testprocedure for fellow researchers to evaluate their capacitivesensors for safe PFL