A system for measuring forces in the legs and crutches from ambulatory patients

A system for measuring force in both legs and crutches or cane during patient walking is developed. The force in each leg is divided into three components. Following measured data during therapy, rehabilitation progress can be established. Pathological gait patterns depending on disease can be estimated. For vertical force measurement in the leg three capacitive sensors are developed. A special sensor based on infrared radiation changes is realized for force measurement in the crutches or cane. To extend a patient´s free mobility, an infrared telemetry system is applied. This specially designed telemetry system with multiple receivers and an intelligent summing unit makes possible free walking to the patient in a large room or in more rooms and staircases as well. All eight channels of measured data are presented in real time on the PC-monitor, where each force component can be displayed separately or in the sum. Afterwards an average of repeated gait cycles or their spectra can be calculated and shown on the monitor.