Grip Pressure and Wrist Joint Angle Measurement during Activities of Daily Life

The goal of this study is to improve future physical human-robot interaction and rehabilitation systems. Experiments were conducted to collect dominant hand grip pressure and joint-angle data during activities of daily life. Representative actions chosen as part of this study were: pushing a weighted cylinder along a flat surface, pulling a weighted cylinder across a flat surface, and lifting a weighted cylinder from a flat surface to shoulder height. Three separate weighted cylinders were used, 3lbs., 5lbs., and 10lbs., and the representative motions were repeated five times for each cylinder. A Tekscan Grip VersaTek Pressure Measurement System and Motion Analysis Cortex System were utilized to collect data. Each subject was outfitted with 18 separate sensorized piezo-resistive tiles placed on their dominant hand and 33 reflective markers at representative locations on their body. The motion of each cylinder was tracked via the placement of seven retro-reflective markers on the cylinder's surface. Analysis of cohort data from five male and five female volunteers, aged between 23 and 51 years, is presented. A Moving Average Filter was implemented to automatically determine contact between the subject's hand and the weighted cylinder. Once contact was determined during an action cycle, maximum detected pressure from each of 18 sensing areas was found. Results report wrist angle during the action- cycle as well as maximum applied pressure during each action across the cohort. Average wrist angle per action-cycle, by action, is also reported for the cohort. These data, along with results from a previous study, will be used improve and verify human intent models for use in future pHRI and rehabilitation systems.