OEM&Lieferant Ausgabe 1/2020

86 Innovations Thomas develops innovative motor pump unit By Thomas Magnete At high speeds, when driving off road, and on bumpy road surfaces, many suspension systems encounter their limits – in the truest sense of the word. What if vehicle springs and shock absorbers were to react earlier and more effectively to uneven surfaces than they do today? Andwhat does that mean for the autonomous driving systems of the future? These are the questions that Mario Kuhl, Head of Technology Development at Thomas, is asking himself. Along with his team, he has developed a motor pump unit with enormous potential … Images: © Thomas Magnete System and functionality In a vehicle suspension system, the springs and shock absorbers undertake important teamwork. They connect the wheel suspen- sion and body, and even out road bumps and surface undulations. The motor pump unit en- gineered by Thomas (or MPU for short) acts directly on the shock absorber or vibration damper. „The MPU ensures that oil is pumped into the damper. It intakes the oil in one loca- tion and pumps it into another location – i.e., it moves the oil from top to bottomor vice versa,“ explains Mario Kuhl. „The vehicle spring vibra- tions can therefore be dampened far more ef- fectively than a classic shock absorber without an MPU is able to do.“ Action, not reaction A higher-level control unit transmits signals to the MPU, which then actively implements them. Sensitive sensors record road surface data and forward them via an intelligent ac- tuator, which in turn controls the anticipated jounce and rebound. Optimal interaction of the individual compo- nents is crucial. „The MPU consists of a BLDC motor, i.e., a brushless DC motor, an oil pump, and the power electronics with motor actua- tion,“ explains Mario Kuhl. „We use pressure ranges in excess of 60 bar – which poses a chal- lenge as regards coordinating the interfaces within the overall system.“ Bumpy was yesterday A driving sensation that aims to separate the body, along with the driver and front pas- senger, almost completely from the course of the road and the condition of its surface. Not only when driving over surface undulations or pot holes but also equally reliably when cornering or changing direction. The MPU eliminates lifting, pitching, and rolling mo- tions in the range up to 10 Hz – performance that particularly benefits front passengers with sensitive stomachs and circulatory sys- tems. „A lot of people suffer from motion sickness, particularly if they are reading a book or looking at their cell phones while the vehicle is moving,“ says Mario Kuhl. „In this regard, the new MPU does more than just increase the driver‘s comfort. It also re- lieves the suffering of passengers, who feel the vehicle‘s compensatory movement much more acutely.“ Significant potential The main thing is four wheels. Whether a com- bustion engine or an electric vehicle is involved – the new system operates irrespective of the drive and offers great promise for applications in a number of other areas such as dynamic suspension systems, in lift systems for level equalization, and in electric oil pumps in auto- mated manual transmissions. The integrated interaction of electronics, hard- ware, and software demonstrates Thomas‘ expertise in developing integrated and smart system solutions which combine the Thomas functionalities of ‚Sense. Think. Act.‘ and thereby create genuine added value. Fully automated driving „As a system supplier with interdisciplinary development teams, we could also implement and supply the electronic actuation for the MPU based on our in-house capabilities,“ says Martin Schmidt, Head of ProductManagement and New Business in the passenger car seg- ment. „Looking to the future of the MPU, fully automated driving also plays a pivotal role, be- cause innovative suspension technology is in greater demand than ever before, especially here. The objective has to be to decouple the vehicle occupants from the driving process and give them the sensation of being in a float- ing living room or office. We are well on track to developing such technology.“ S H A R E Thomas Magnete www.thomas-magnete.com Website Mario Kuhl (left) and Martin Schmidt