Reliable switching for public transport

When a trolley bus reaches a road junction, wire-switches, installed on the overhead conductor cables, control its direction of travel. Switches may be in the default “straight-through” position or in “turnout” position. As a bus passes a switch in turnout position, a sensor mounted on the overhead cables detects the presence of the current collector.…

Position control in harsh environment

A manufacturer of bulk material-handling equipment uses Radio Frequency Identification (RFID) technology to sense the position of a large rail-mounted reclamation-conveyor operating in a hot, dusty environment. A pair of read-write modules, mounted on the machine structure, interrogates a series of RFID tags, positioned at one-meter intervals along each travel rail. The control system identifies…

Accurate road bridge positioning

Modern road bridges typically utilize beam construction, in which mobile cranes lift prefabricated bridge sections onto pairs of support columns. Multiple heavy-duty hydraulic cylinders support the ends of each section, allowing accurate height adjustment prior to final positioning. Engineers require rugged sensor systems that detect the position of each cylinder accurately. Sensors should be mechanically…