Analysis of variability in pylon transducer signals.

A pylon transducer has been used to provide force and moment data relating to the stance phase of gait of below-knee amputees fitted with modular types of PTB prostheses. The data has been collected and modified using digital processing systems with particular interest in quantifying shape differences in the loading information curves. Earlier tests illustrated the need for more data to provide statistical support for conclusions. However, the requirements for more data greatly increased the data handling and storage problems. A method was devised whereby those features considered significant from an information point of view could be extracted from the transducer signals and then combined. The statistical combination of features was made to allow objective comparisons of strides for a particular subject.