Wireless Brake Shoe Force Measurement System

Railroad freight car safety and maintenance cost is directly related to knowledge of the actual braking force provided by a brake shoe. If the brake force is too low, safety is at risk. If the brake shoe is replaced before the end of it's lifetime to ensure safety, maintenance and thus operating costs are increased. Currently there is no system in place to monitor brake shoe force during train operation. Mide has constructed a feasible self-powering brake shoe force measurement system design based on Phase I trade studies, prototypes and testing. The system includes a piezo electric energy harvester that powers a system consisting of a low power strain measurement device as well as data storage wireless transmitting capability. Strain is measured via high temperature strain gage capable of operating in presence of extreme thermal loads. This system will wake up during a brake event, record data until the brake force has subsided and wirelessly transmit the data to a central location for reduction and analysis. Since the system is self-powered it will never need to be serviced for battery replacement.