Biomechanical P ... Slalom Water Skiing R1.pdf - Atrium - University ...

tip. The IMU housing was wrapped in plastic and strapped to the plate. Data from thesensor was transmitted, via custom RF transmission system, to a computer (Acer AspireOne ZG5, Acer America Corporation, Mississauga, ON) located in the toe boat. The RFtransmission system consisted of two custom designed RF units, one located on the skiand the other was connected to the computer via universal serial bus (USB) port. Eachunit had two RF transceiver modules (nRF2401, Nordic Semiconductor ASA, Tiller,Norway) that were operated by a micro controller. The data was parsed by the computerusing a custom data collection program (Labview 8.2, National Instruments Corporation,Austin TX). The data output from the sensor was received as a digital signal and then wasconverted to an analogue output via the data collection program.Each subject was required to perform one test run on each of the four skis. The skisvaried in classification from “performance” to “tournament”. A brief summary of the skiscan be found in Table 2 and a sample ski profile can be seen in Figure 2. A randomizedprocedure was used to help minimize the effects of fatigue and changing weatherthroughout the day. To further minimize the factors that would influence the results, all ofthe ski runs were done on the same slalom course with the same rope length, 17.9 m.Boat speed was controlled using an automatic control system that was set to 51.5 km/hfor all of the experimental test runs.87