Conduct-by-Wire : following a new paradigm for driving into the future

This paper presents a new concept for future cars combining potentials of Advanced Driver Assistance Systems (ADAS) and X-by-Wire technology. Based on current developments in technology ADAS will cover a great part of standard traffic situations and offer assistance on the conducting level to the driver. As a result, in addition to basic driving functions on stabilising level assumed as fundamental so far (steering, braking, accelerating), the driver now has to deal with the operation of a greater number of control elements and furthermore the attention to new display elements. Beyond the extension of the Human-Machine-Interface (HMI) interdependencies between assistance and basic driving functions now arise, which are associated with the new requirement for the driver to be aware of which functional mode the vehicle is in. The idea of Conduct-by-Wire is to transfer the vehicle control from stabilising to conducting level. Driver assistance functions and basic operations (steering, braking and accelerating) are an integral part of a vehicle guidance system which communicates with the driver on manoeuvre basis. For this, a large number of developments of operational elements can be mentioned which range from multifunctional elements similar to a steering wheel or a joystick. Indeed, instances of these forms are known from various X-by-Wire concepts. Unlike them, the operational units of Conduct-by-Wire serve as a command interface for manoeuvres and appropriate parameters. A vehicle with such an HMI will transform the various inputs of the conducting function in a motion vector and convert it into motion on the stabilising level without the driver's help. As a result a mechanical or hydraulical coupling between operational element and wheel actuator becomes useless, so that an underlying X-by-Wire architecture has to be chosen logically. The Conduct-by-Wire concept breaks away from the paradigm of a driver interface on the stabilising level and chooses the conducting level instead. As a result consistent and simplified vehicle guidance is realized, which provides the most of the ADAS-functionality without removing the driving responsibility from the driver. A further advantage of this concept is the simplicity of the vehicle's architecture with a very simplified command flow with no need of coordination between the functions of the controlling systems, i.e. a motion vector is absolutely sufficient for the control of the underlying X-by-Wire systems. TECHNICAL PAPER - Driver Assistance Systems considerably contribute to facilitate vehicle guidance (1) and improve the total efficiency of the driver/vehicle unit in many situations. However, these systems' control complexity increases with every rise of the assistance degree. To ensure the safe use of assistance functions in the intended way the driver must possess the necessary functional knowledge.