Implementation of a Local Interconnect Network over a DC-Bus for Reduction of a Vehicle Wiring Harness

The paper discusses the development and implementation of a form of in-vehicle communications for the body control in an Ariel Atom niche sports car. A Local Interconnect Network (LIN) bus has been developed that runs the LIN signals over the power lines of the vehicle wiring harness. The LIN system has one master and up to 15 slave ECUs. LIN is normally run at a maximum bit rate of 20 Kbit/s, however this system has been implemented at 57.6 Kbit/s by modulating over the power lines. Benefits of this approach include weight reduction, reduction in the number wires, ease in retro-fitting to existing vehicle architectures as only requires a connection to power lines and the ability to monitor the signals via the battery pins of the OBD connector of the vehicle. The approach has resulted in a reduction in weight due to wiring and electronic control unit reduction. The minimal bodywork design of the Ariel sports car means that unnecessary wiring is not so aesthetically pleasing and therefore the reduction in wiring required is one way of making the harness more pleasing to be seen. Future development will look into increasing the bit rate to 115.2 Kbit/s and implementation of redundant channels for back-up to improve robustness for safety critical applications.