Wearable swimming technologies
Using a small wearable device a swimmer can now train in their own pool and on their own but gather performance data like they were supported by coach and timekeeper and in an instrumented pool with video analysis. In general the measurement of sport specific performance characteristics is an important part of an athletes training and preparation for competition. Thus automated measurement, extraction and analysis of performance measures is desired and addressed in this paper. A tri-axial accelerometer based system was located on the lower back of swimmers to record acceleration profiles. The accelerometer system contained two ADXL202 bi-axial accelerometers positioned perpendicular to one another, the system could collect several hours worth of data. Simultaneous video and electronic touch pad timing was recorded for validation. Algorithms have been developed to derive lap times and stroke counts from the accelerometer data. Comparison against electronic touch pad timing against accelerometer lap times has produced results with a typical error of better than ±0.1 seconds. Video comparison of stroke count algorithm for freestyle also produced results with an average error of less than a single stroke.
The results have an improved reliability as compared to hand timed and counted data but with out requiring additional people to do this wrok. Thus the athlete is free to train in any pool and have every sessions metrics recorded.
Next generation research is putting sensors on the hands and monitoring the propulsive forces as well to help improve technique more directly.