Schaeffler Paravan Space Drive – the modern drive-by-wire system
Space Drive is a perfectly coordinated drive-by-wire / steer-by-wire system (hardware and software) that incorporates a new and revolutionary safety concept. The system is individually adaptable to an extremely wide range of safety-related applications in the automotive sector, in agricultural technology, in construction-machine technology, in municipal vehicles and special-purpose vehicles, and in the defense industry. It has also been used to create a distinct segment in the disabled mobility sector. The Space Drive operating system, which consists of a three-stage multi-redundant motor-driver and control system for all common electric motors (60 A/DC 12–24 V), is suitable for use in applications with the highest safety requirements. Depending on the area of application and customer requirements, the system can be supplied in subcomponents and specially customized software modules. The system’s processor unit (ECU) meets the most demanding requirements in accordance with the ISO 26262 ASIL D safety standards and is also manufactured in line with the highest safety standard (IPC A 600). In addition, the Space Drive system is road-approved for the international vehicle types M1, M2, M3, N1, N2, and N3.
What are the components of our drive-by-wire system for automated driving?
The heart of the Space Drive system is a newly developed CPU with a perfectly coordinated software package and an innovative and revolutionary safety concept. The CPU and software perform realtime processing of digital (CAN/FlexRay/LIN) or analog (joystick, steering wheel) input signals that contain essential vehicle data – for example on braking and speed. They then forward these signals, which also undergo logical validity checks, to servo motors that control the gas and brake pedals, as well as steering. A large selection of additional analog input subcomponents that were developed in-house are also available. These include steering wheels (steer-by-wire) with digital force feedback technology, joysticks / acceleration-braking levers, and rotation handles. The system’s comprehensive package is rounded out by high-performance servo motors to control steering, acceleration, and braking, as well as specially aligned safety cable harnesses for automated driving. The Space Drive system is approved for road use in accordance with the ECE-R 13, ECE-R 79, and ECE-R 10 standards.
Whether it’s mobility solutions for people with disabilities, automated industrial applications, or dangerous jobs – with nearly one billion kilometers already driven “by-wire,” Space Drive technology from Schaeffler Paravan offers a proven and safe control system for innovative vehicle operation.
This system is used in industry for dangerous jobs, as well in vehicles designed for people with disabilities. In the latter case, it makes it possible for individuals with paraplegia or other physical limitations to enjoy independent mobility.
The safety concept – FAIL-OPERATIONAL (fail-operational system performance)
The highlight of the PARAVAN steer-by-wire system is based on a multi-active redundant safety architecture. What lies behind this innovation? As mentioned, input signals are transmitted to the system for processing in analogue or digital form via various interfaces (CAN, LIN, Flex Ray). The heart of this new and revolutionary PARAVAN safety architecture is the fact that three processors immediately take over the task of controlling the vehicle at the same time and simultaneously check their values with one another. All the control signals of the three processors are then compared in a logic comparator (CPLD). In accordance with established criteria, the CPLD decides which processor control signal is selected and is transmitted to the actuators via the three H bridges available. The development of the new SPACE DRIVE II system has been influenced by over ten years of experience that has seen first-generation PARAVAN drive-by-wire systems sold by the thousand.
What advantages does the new Schaeffler Paravan system offer for autonomous driving?
In addition to the revolutionary multi-redundant safety architecture and the associated fail-operational system operation, the new Schaeffler Paravan Space Drive system offers other advantages that will radically change not only automated driving but also driving in general in the future. For example, the use of Space Drive will make the steering column – one of the main sources of injury within vehicles – superfluous. The drive-by-wire concept from Schaeffler Paravan also makes the mechanical connection between input devices and axles obsolete. Safety cables and servo motors will take over the function of the pedals and steering column in a reliable and fail-operational manner without the driver having to accept restrictions on driving comfort or enjoyment. With Space Drive, we are already able to post lap times with steer-by-wire that are similar to those achieved with a conventional steering wheel and steering column. Initial studies also show that driving with the drive-by-wire system gives drivers greater freedom to concentrate and pay attention because the complex motor coordination of arms and legs while driving is no longer required. With Schaeffler Paravan, drivers are more comfortable, more relaxed, and safer on the road. The omission of the steering column will also result in completely new interior concepts. More vehicle-monitoring options and interactive multimedia applications can be implemented using larger display surfaces, for example. The vehicle can be controlled from the driver’s or the passenger’s side without significant or expensive structural alterations. This means that lightweight vehicles can be built that boast lower fuel consumption, greater driving comfort, and enhanced safety. With the Schaeffler Paravan system, the vehicle can already now be controlled via a wide range of input devices, thanks to numerous analog and digital system interfaces. Control via joysticks, GPS, laptops, smartphones, apps, and even radio is not an idea – it’s already a reality. The first road trials have been successfully completed. The technology also makes it possible to use vehicles in potentially dangerous situations, in which the driver can get out of the vehicle, set the control to remote, and control the vehicle from the outside. Thanks to this versatility and the installation of additional sensor systems, even semi-autonomous or completely autonomous driving is no longer a futuristic vision.