Data acquisition system for measurements in free moving subjects and its applications

Abstract

A low-cost, portable acquisition system for monitoring and processing human biomechanical parameters is presented. It is equipped with 16 input channels, each one linked to an external transducer by a suitable connector. Input signals from sensors are converted into a digital form by a 12-bit analog-to-digital converter and stored in a removable memory (memory card) respecting the PCMCIA standard interface, allowing the download of acquired data toward the host computer. The acquisition operating mode is programmable by a host PC, writing proper values into the memory card; then, the instrument acquires the defined number of channels at the selected sampling rate. The instrument is battery powered; then, it can be used in all those applications, like rehabilitation and sports medicine, where the freedom for subject movement is a constraint for the test. In fact, this instrument does not require an arranged environment for measurements, and it is not connected to a PC. Three sample applications are presented in which the instrument is used to evaluate human motor capability, physical parameters in amputees, and motor performance in athletes.