Rider Assistance Systems On Pedelecs

20 May 2021 Vehicle Technology
Sales figures for pedelecs have been rising steadi-ly for years. Even despite the coronavirus crisis, they do not seem to have declined – quite the opposite in fact. One of the reasons for the electric bicycle’s success is the fact that it appeals to people of every age demographic. Older cyclists in particular can benefit from the vehicle’s intuitive handling, high average speed and ability to navigate inclines easily, all of which significantly extend the user’s radius of activity while ensuring that they get still a healthy amount of exercise. However, the rising number of pedelec accidents involving older riders indicates a definite need for rider assistance systems that either prevent accidents completely or at least minimize their severity, as this section of our population will continue grow.
One system that offers particular promise in this respect is the Bosch anti-lock braking system. This assistance system, described in detail in the 2020 DEKRA Road Safety Report, prevents overbraking on the front wheel of the pedelec. The significant benefit of the system is not so much that pedelec riders can keep steering during heavy braking, as the fact that it saves them from losing control when the front wheel locks up. This makes it safe for pedelec riders to use their front brakes with the maximum possible deceleration, without the risk of their front wheel slipping or them being thrown over the handlebars.
In order to determine other potential areas for improvement, safety-related driver assistance systems that have already proven effective in other vehicle classes were taken as the starting point for the SIFAFE research project, which focuses on safety- oriented rider assistance systems for electric bicycles. The systems needed to be evaluated in order to determine their suitability for use in electric bicycles, before being adapted and developed further. This process took into account both vehicle-related parameters (feasibility of installation, power requirements, robustness, cost) and transport science factors (effectiveness, user acceptance, distraction levels during operation). The objectives of the project were to analyze the potential of safety-related assistance systems for electric bicycles, design and build sample systems, and evaluate their performance.
In order to analyze cyclist safety, a pedelec accident and system effectiveness analysis was conducted during the course of the project. Unfortunately, there were weaknesses in both the interpretation of the results of this analysis and the conclusion that resulted from it. However, the analysis of the accident does allow us to conclude that the prioritized systems offer great potential for preventing a large number of accidents, or at least reducing the severity of their consequences. There is huge market potential in this respect: a survey of 300 users has shown that many of them would like such assistance systems. Like-wise, there is a high level of acceptance for rider assistance systems among the general population. More than 80 percent of those surveyed said that they had a positive attitude toward rider assistance systems, and 66 percent were willing to pay up to an additional 300 euros to have such assistance systems on their electric bikes.
In the practical section, systems designed specifically with senior citizens in mind – such as lane departure and frontal collision warning systems – were rated as reliable by two thirds of the riders who participated in the test. The results of the riding tests, in which a variety of warning strategies were also evaluated, showed that haptic rider warnings in the form of vibrating handlebars were deemed to be particularly intuitive – even more so than visual and acoustic warnings. In one example of such a system, the right handlebar vibrates when the pedelec veers too close to the right edge of the lane, the left handlebar vibrates when the pedelec veers too close to the left edge of the lane, and both handlebars vibrate simultaneously when there is a risk of a frontal collision. Overall, the study shows that assistance systems can also help to improve safety on electric bicycles, and that there is a huge need for further research in this area.