Smart steering from Bosch Servotwin

By Categories: Commercial NewsPublished On: Tuesday 28 June 2022

Vehicle technology provider Bosch has detailed the features and benefits of its Servotwin electrohydraulic steering systems for commercial vehicles.

“There is a long list of commercial-vehicle assistance systems based on the connectivity of steering systems and onboard electronics,” said the company.

“These include highway pilots, traffic-jam assistants, blind-spot assistants, automatic emergency braking on vulnerable road users, adaptive cruise control (ACC Stop & Go), lane-departure warning systems, turning assistants, manoeuvring distance warning systems and many more.

“To facilitate such features, an increasing number of commercial vehicles are equipped with Servotwin electrohydraulic steering systems.”

The commercial vehicle manufacturers’ demand for these steering systems is continuously growing, says Bosch; and several modern CVs are already equipped with electrohydraulic steering such as Bosch Servotwin, with the number expected to grow in future. For workshops, this means Servotwin is likely to appear more often on service schedules.

“The electro-hydraulic Bosch Servotwin steering system basically consists of the RB-Servocom hydraulic ball-and-nut power steering system and a platform-based combination of an electric motor with control unit and a worm-gear transmission,” the company explained.

“The ball-and-nut power steering system – based on the principle employed in a classic hydraulic power steering system – provides most of the steering assistance. An oil circuit and a power cylinder provide the hydraulic steering assistance.

“In addition, a turning motion of the steering wheel and the steering moment applied are detected by turning-angle and torque sensors and transmitted to the integrated electronic control unit.

“Taking other vehicle parameters into account – for instance, speed and load – it then determines the required additional steering moment. By means of an electric motor and a worm-gear transmission, the additional steering moment then acts on both of the input shafts of the RB-Servocom, thus assisting the driver when steering.”

Due to the connection of the steering system to the onboard electronics, Servotwin is not only suitable for its integration into comfort and driver-assistance features, adds Bosch, but also into automatic driving functions.