This thesis addresses the problem of designing, manufacturing, and testing a system for capturing the force of interaction on a robotic device for fingers and wrist exercises. The goal of the thesis was to develop a measuring system that captures force at the distal support of the mentioned device. The operation principle of the measuring system is based on strain gauge technology. The device is intended primarily for patients rehabilitating after a stroke. Accordingly, the first part introduces the etiology of stroke, the rehabilitation process after this condition, as well as the introduction of robotic devices into this process. Subsequently, possible methods for capturing the force of interaction and the description of the selected method using strain gauges are described. Their operating principle is presented, as well as possible configurations of the Wheatstone bridge, on which the operation of our measuring system is based. This is followed by a presentation of the circuitry with which we properly amplified the bridge output and enabled data reading, which took place via Raspberry Pi microcomputer. To gain insight into the operation of our measuring system, its characteristic features, such as response linearity and changes in offset were measured. The amplified data that we captured during the measurement were in raw format, so we developed software codes with which we calibrated the system through two steps. In the first step the calibration process, was performed through measurements with known weights. The second, more precise step, was carried out using a robotic system equipped with a calibrated reference force measurement system. Within each step, we calculated a conversion factor that converted the raw data into the desired physical quantity. Using the calculated conversion factors, we developed software code that enables force capturing and real-time plotting of its course. Lastly, the results of the measurements captured with our measuring cell are presented, along with the conclusions that we reached during the development of the measuring system.
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