The frictional heat generated by breaks when decelerating a vehicle can have various negative effects on the brake system. Besides possible thermal cracks in the brake disks, premature wear or brake failure, an additional critical aspect is an increased braking distance can occur as a result of friction coefficients changing with higher temperatures.

Ankers supports its customers in the development of new products by providing simulation, design, and development services. Among other areas, the company specializes in special car development from scratch including electrical and ICE vehicles, one of f super cars, and race cars for several European and Chinese automotive OEMs and tier one suppliers.

Ankers' engineers aim to be at the forefront of technology and are using state of the art tools and development methods. One of their chosen tool sets is the Altair's HyperWorks suite, with which Ankers' simulation team has been working since its foundation in 2014. The tools have been used in numerous simulation and development projects, among others for structural analysis and optimization tasks. Especially in e-mobility projects, but also in any project in which the entire system with all its different aspects has to be developed. Co-simulation and a model based development approach of fers answers, which an approach that only considers single applications can't provide. So when co-simulation became a topic for Ankers, the engineers turned to Altair to see what the software provider had to offer.

In one of the company's recent projects, the Ankers’ engineers conducted a feasibility study to determine the thermal influence on a brake system. To do so, the engineers made a co-simulation, applying MotionView, the multibody dynamics tool of the HyperWorks suite, and Activate, a solution to simulate and optimize multi-disciplinary systems using a 1D approach. The goal of the study was to show that simulation results would be more accurate when considering the thermal effects via co-simulation and to demonstrate the company's co-simulation competences to its existing and future automotive customers.

MotionView and Activate in the Development Process

The models used in this study were a full vehicle model and a model of the brake system, comprising of the brake disk and the brake pad. Both models were created in MotionView, using some of the various system templates the software offers via its vehicle library. To include the thermal influence caused by the energy conversion during braking, the multi-body system was co-simulated with Activate. In this way it was possible to study the influence of the temperature due to the disk-pad contact on the braking distance. The co-simulated model was set up in MotionView (multi-body system plus advanced driver) and Activate (friction-thermal dependent model). From MotionView the line pressure and the wheel angular velocity were fed into Activate to compute the friction coefficients according to the thermal model and the hydraulic circuit. This result was then again fed back into MotionView to update the properties of the acting model components. The simulated maneuver was braking on a straight route; the analyzed brake system can be ventilated through testing data. In this case, a non-ventilated model was used.