This is a new system being demonstrated by ZF in Germany in its ‘Innovation Truck’ demonstration vehicle. The truck uses a combination of technologies from both ZF and Bosch. When the double is required to handle some tight manoeuvring, especially when reversing, the driver gets out of the vehicle and moves the truck onto a loading bay using fingertip control using an app on a tablet. The system allows them to move either the rear trailer or the prime mover from left to right. The driver is then able to walk around the reversing vehicle moving it into position precisely. At the same time, the control system makes the correct steering inputs to move the trailer in the desired direction.
At the heart of the new system are three technologies, combined to produce the desired result. Firstly, the transmission is ZF’s innovative Traxion transmission, which combines a basic automated manual transmission with a choice of a number of clutch options. In this case the option in the clutch position is a hybrid system with an electric motor integrated into the bell housing capable of delivering 160 hp and 1000 Nm of torque to the driveline, on its own when the diesel engine is turned off. A dry clutch is installed in the hybrid module, in addition, to enable manoeuvring on only electric power.
The second component used is the ZF Servotwin superimposed steering system. This uses an electric motor in addition to the truck’s diesel engine-driven hydraulic pump, which provides the power. The system is able to perform autonomous steering maneuvers with no driver intervention at the steering wheel. Enabling remote control of the truck’s manoeuvring. In the case of the Innovation Truck, ZF have gone for, what they call, zero emissions manoeuvring with a modified hydraulic pump able to work without power from the engine. It’s a electrohydraulic solution (electrohydraulic power steering or EHPS), two ZF-Servotwin powerpacks drive the modified pump.
Controlling what’s going on, the Openmatics telematics application, consists of an onboard or connectivity unit, sensor technology for data recording, and specially developed software. The system uses wireless detection of both articulation angles of the semitrailer and the rear trailer for steering control, plus the relative position of the driver and the tablet to the vehicle/trailer combination. The telematics use ‘Bluetooth Low-Energy’ (BLE) tags, which are wireless chips with low-energy requirements and a range of approximately 25 metres. These are located on the back of the cab and on each corner of the semitrailer and trailer.
The system has been developed as a debate continues in Europe about whether to allow longer, double trailer combinations on the highways across the continent. This innovative solution answers one of the issues around driver skills and safety in loading and unloading situations.
ZF’s ambition doesn’t stop there, they are already planning completely automatic reversing and manoeuvring systems.
“From a purely technical point of view, it would also be possible for trucks at the depot to move to the loading ramp or parking position completely on their own, i.e., even without the remote control app,” said Olrik Weinmann, Project Manager in Advanced Engineering and Testing at ZF, the man responsible for the Innovation Truck. “This, however, requires a different infrastructure at the depots and is thus a vision for the future.”