Daniel Smith, Brigham Young University
Engineering
Although it is known as a graceful sport, figure skating can take a serious toll on skaters’ bodies. Considering that figure skaters commonly train five days per week, with 50-100 jumps per day, it is not surprising that repetitive stress injuries are a serious issue in figure skating. Because the forces associated with these jumps are poorly understood (including their magnitudes, loading rate, and when they occur) training plans designed to prevent injury are incapable of preparing athletes to best avoid their negative effects.
There is currently no tool capable of appropriately measuring impact forces during figure skating jumps on ice. Force plates are useful in off-ice simulated jumps, but differences in take-off velocity, angular velocity, technique, and surface friction make it difficult to correlate these forces with those on-ice. On-ice studies have been performed with hockey skates; however, the subjects of these studies were cumbered in ways not feasible for figure skating.
The purpose of this research is to create a light-weight, wireless, force sensing system capable of non-obtrusively measuring impact forces during figure skating jumps. We applied strain gauges (in half-active Wheatstone bridge circuits) to the stanchions of a figure skate blade in alignment with the vertical and horizontal axes of the skate. During skating, the voltages from the bridge circuits are processed and recorded by a 16-bit ADC convertor located between the sole of the boot and the blade.
Preliminary validation tests on this apparatus shown its feasibility. The output from the system compares favorably with data simultaneously recorded on a force plate, showing similar maximum forces and load profiles. Current research focuses on including all impact angles, reducing the effects of temperature, attenuating noise, and making the system more robust.