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PubMed · 4469157

Pulse code modulation telemetry in ski injury research. I. Instrumentation.

M L Hull·C D Mote
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Abstract

Measurement problems can be classified into instrumentation, data transmission and recording, and analysis. This paper focuses on the transmission of multichannel, high-volume, high-frequency, high-accuracy data. Boot-ski dynamometer and skier velocity anemometer data provide 13 channels of max. 8-mV signals requiring 8-microvolt resolution or 4.45-Newton dynamometer resolution. The data transmission system features durability, power consumption approx. 10 Watts, weight 4.54 kp, range greater than 3,500 m, frequency response 250 Hz, accuracy 1 per cent, temperature stability, dynamic range plus or minus 2 inches. The transducer signals are ampflified to plus or minus 10 V for the 100-kbps PCM system. Special AC amplifiers, driven by an amplitude-stabilized power oscillator, were designed for elimination of radio frequency interference (RFI), improved stability and high signal/noise. Sixteen words are sequentially sampled at 521/sec-13 data, 2 frame counters, and 1 sync. The ground station consists of the PCM decoder with real-time capability and an analog tape recorder. Data is subsequently buffered and formatted onto digital tape by mini-computer.

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Athletic InjuriesComputersHumansSkiingTelemetryJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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M L Hull, C D Mote. 1974. Pulse code modulation telemetry in ski injury research. I. Instrumentation.. https://pubmed.ncbi.nlm.nih.gov/4469157/

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