On 20 June 2024, the Austrian Road Safety Board selected the diploma thesis "Conception and implementation of a brake-by-wire system for e-scooters" by Dipl.-Ing. Stefano Cavosi (TU Vienna) as the winning project of the KFV Research Prize 2024 at a gala evening at the Vienna Museum of Technology. Artificial intelligence & digitalization, climate change and child safety in the context of prevention were the topics of this year's competition.

As part of several diploma theses, an experimental test setup for an innovative driver assistance system to support the braking of vehicles in the field of micromobility, especially e-scooters, was developed at the Institute of Mechanics and Mechatronics' Technical Dynamics and Vehicle Dynamics research department.

E-scooters are a popular means of transportation in urban environments. While driving an e-scooter is quite easy after initial practice, driving safety is a critical issue, as evidenced by an increasing number of accidents and injuries.

One technical disadvantage is the poorer braking performance compared to other vehicles that share the road. As a rule, braking distances are (too) long and deceleration is (too) short. A great deal of experience is required to handle the front and rear brakes effectively, and only experienced drivers are able to use the potential of both brakes in combination and also avoid a rollover under heavy braking. Another challenge is wet or slippery road surfaces, where it is difficult to avoid sliding sideways and thus a fall by over-braking.

As a technical solution to improve braking behavior, a new brake assistant in the form of a brake-by-wire system was developed and implemented in a test vehicle. This allows the front and rear brakes to be actuated with a common control element and the braking forces to be optimally distributed between the front and rear wheels. The braking force distribution must be determined depending on the mass characteristics of the driver, the standing position and the road conditions. This can also actively prevent one or both wheels from over-braking and the rear wheel from lifting off the ground.

Micro-Mobility: Brake-Assist for E-Scooters

The experimental test vehicle set up by Stefano now offers many possibilities. For example, the multi-body system model of e-scooter and driver developed at the research department could be validated, especially the unknown tire characteristics on different road surfaces. Furthermore, various effect- and cause-based methods, e.g. with a wetness sensor, for friction value estimation are being further developed and tested. In future, it will be possible to analyze the human-machine interaction in the simulation and on the test vehicle, as well as the acceptance of the one-hand operating element ("hmi-interface"). A major challenge is the robust real-time estimation of the mass properties and the stance position, which are also measured on the test vehicle for validation.

Contact

Dr. Florian Klinger (TISS, opens an external URL in a new window)

Institute of Mechanics and Mechatronics

RU Technical Dynamics and Vehicle System Dynamics

TU Wien

Getreidemarkt 9, 1060 Wien