Development of a Prototype for the Simulation of Human Sway to Make Standardized and Reproducible Measurements of Force and Pressure Sensors

AbstractForce and pressure sensors are commonly used in systems to measure balance and postural sway. When it comes to biomechanics in sports, trainers and therapists often rely on those measurement methods to set up rehabilitation and performance enhancement exercises. To prove sensor reliability and the comparability of various systems, a programmable human sway simulator (PHSS) apparatus was developed to enable standardized and reproducible human-like load simulations. The apparatus can be used to test computerized dynamic posturography (CDP) systems, instrumented balance and training systems or any static sensor of that kind. Results from CDP systems provide information for a more efficient and focused athlete coordination training. Due to the variety of CDP instruments on the market the question arises, whether these systems provide reliable results. With the developed prototype impartial comparison of these systems will be possible. For the test procedures it is required to create predefined sway patterns with varying loads to simulate human mass from kids to adults. These loads have to be applied over footprints representing the human forefoot and heel. The conceptual design of the PHSS was performed using reliable industry standard components for rapid production. The operating system simulates the motion of human mass via four separated DC-Motors in order to record indicators of the tested system such as center of pressure (COP), range of motion (ROM) and applied load frequency. Besides that, the PHSS includes a monitoring of motor positioning to retrieve operation indicators for self-check and calibration. With all that, the PHSS allows direct comparison of CDP systems that record ground reaction forces (GRF) or verify the long term precision of sensors as a quality assurance tool. This enables higher standards for training and testing systems and more precise conclusions about human balance abilities and training conditions