摘要: |
Technology offers a significant potential to improve the productivity and safety of the motor carrier industry. To date, the application of new technology to commercial vehicles has been limited to single unit trucks and truck tractors because of constraints inherent in the present combination-unit truck trailer electrical powering and communication system. A number of possibilities have been suggested to address this issue including, but not limited to, radio/telemetry communication among units in the combination, multiplexing, voltage enhancement, wiring system upgrade, and additional electrical circuits. This report explores the multiplexing approach. This approach switches six of the seven wires in the standard SAE J1067 cable and J560 connector to two J1939 communication lines and four full time power lines, leaving one wire for ground. The system uses personal computer hardware and power switching in custom modules. Additional safety and productivity enhancing features have been added to the combination unit to demonstrate the potential of the systems. These features are: 1) advanced lighting multiplex modules, 2) trailer ID, 3) trailer air brake reservoir low pressure, 4) ABS warning light in the cab, 5) trailer parking brake status/brake status, 6) trailer air suspension pressure, 7) tandem axle load, 8) rear object detection, 9) side object detection, and 10) refrigeration status in the trailer. |