|
This thesis is going to develop a fully automatic human body jumping ability measurements system by using a set of 3-axis MEMS accelerometer, associated NI Wi-Fi DAQ (Data Acquisition Device) and LabVIEW system development platform. The main LabVIEW automatic system is a real-time execution program which provides 3-axis acceleration raw data inspection, sensors bias and scale factor errors update, physical data conversion, speed and displacement integration, Azimuth angle, Elevation angle, maximum displacement or jump height, jumping force, jumping reaction time etc. All these process results display on Human Interface Screen in digital and graph form. Specially, 3-D body motion trace in space is included which can explain the jumping performances evaluation. Finally, the measurement results will stored in personal file. This project mostly concerns the measurement accuracy which judges the jumping ability. The most part this thesis discuss and simulates the 3-axis MEMS Accelerometer Errors effect by using MATLAB Simulink Tools. Dominate error sources to contribute displacement error are come from Bias and Sensitivity of MEMS ADXL335 accelerometer. However, we develop an Error Update Technology can reduces this effect to minimum level and good enough for applications. The 3-axis accelerometer module, power supply and Wi-Fi DAQ module are packaged into a whole set, and strop down this set on body. The real jumping tests are provided and compare with actual height meter. Accuracy is fine. Using this approach we can improve the measurement system by eliminating the uncertainty from traditional method, includes testing environment, subjective criteria, and muscle fatigue. The collected data could also be used to establish a personal or public database for medical personnel to evaluate or advice testers for better health condition. This database could also help selecting athletics. Keyword:MEMS Accelerometer, Jumping Ability, LabVIEW Automatic System, NI Wi-Fi DAQ, Error Update Technology, MATLAB Simulink Tools, 3-D body Motion Trace, Error Analysis
|