Investigating cycling kinematics and braking maneuvers in the real world: e-bikes make cyclists move faster, brake harder, and experience new conflicts

Abstract

Pedelecs (e-bikes), which facilitate higher speeds with less effort in comparison to traditional bicycles (t-bikes), have grown considerably in popularity in recent years. Despite the large expansion of this new transportation mode, little is known about the behavior of e-cyclists, or whether cycling an e-bike increases crash risk and the likelihood of conflicts with other road users, compared to cycling on t-bikes. In order to support the design of safety measures and to maximize the benefits of e-bike use, it is critical to investigate the real-world behavior of riders as a result of switching from t-bikes to e-bikes. Naturalistic studies provide an unequaled method for investigating rider cycling behavior and bicycle kinematics in the real world in which the cyclist regularly experiences traffic conflicts and may need to perform avoidance maneuvers, such as hard braking, to avoid crashing. In this paper we investigate cycling kinematics and braking events from naturalistic data to determine the extent to which cyclist behavior changes as a result of transferring from t-bikes to e-bikes, and whether such change influences cycling safety. Data from the BikeSAFE and E-bikeSAFE naturalistic studies were used in this investigation to evaluate possible changes in the behavior of six cyclists riding t-bikes in the first study and e-bikes in the second one. Individual cyclists' kinematics were compared between bicycle types. In addition, a total of 5092 braking events were automatically extracted after identification of dynamic triggers. The 286 harshest braking events (136 cases for t-bike and 150 for e-bike) were then validated and coded via video inspection. Results revealed that each of the cyclists rode faster on the e-bike than on the t-bike, increasing his/her average speed by 2.9-5.0 km/h. Riding an e-bike also increased the probability to unexpectedly have to brake hard (odds ratio = 1.72). In addition, the risk of confronting abrupt braking and sharp deceleration were higher when riding an e-bike than when riding a t-bike. Our findings provide evidence that cyclists' behavior and the way cyclists interact with other road users change when cyclists switch from t-bikes to e-bikes. Because of the higher velocity, when on e-bikes, cyclists appear to have harder time predicting movements within the traffic environment and, as a result, they need to brake abruptly more often to avoid collisions, compared with cycling on t-bikes. This study provides new insights into the potential impact on safety that a cycling society moving to e-bikes may have, indicating that e-cycling requires more reactive maneuvers than does cycling traditional bicycles and suggesting that any distractive activity may be more critical when riding e-bikes compared to traditional bikes.

Prospects of Electric Vehicles in the Developing Countries: A Literature Review

“…The lead-acid battery used in E2W is considerably heavier than lithium-ion batteries [31]. Additional weight can also be problematic in applying brakes or manoeuvring the E2Ws [125]. As lithium-ion technology is expensive, people of the developing countries would rely on the lead-acid battery for their E2W.…”

A Scientometric Review of Powered Micromobility

“…The review also demonstrated that many European nations have extensive experience with various forms of powered-micromobility particularly powered two-wheelers and electric bicycles, with research identified in numerous European countries including the Netherlands, Italy and Sweden [49][50][51]. Furthermore, conceptual models for investigating emerging vehicles have been developed and could be applied to better understand new and emerging forms of powered microvehicles [26] and investigate specific issues in new jurisdictions.…”

E-bikers’ braking behavior: Results from a naturalistic cycling study

“…Braking events were further classified as unexpected when the manoeuvre was a reaction to avoid a conflict, in contrast to a planned braking to pro-actively regulate speed during routine cycling. A comprehensive description of the definition of the selected subsample of unexpected events (51 cases) by video analysis can be found in Huertas-Leyva et al (2018). The remainder of the identified braking events (1515 cases) were considered as braking events during routine cycling.…”

“…Consequently, e-bikers may be exposed to more complex traffic situations (Reynolds et al 2009) and may be more susceptible to the reduced perceptual capacity and stability coming with ageing (Boele-Vos et al 2017;Kovácsová et al 2016). The operational speed increase seen in e-biking (Huertas-Leyva et al 2018;Schleinitz et al 2015) may also have severe implications for road safety (Dozza 2013) due to the difficulty other road users have in perceiving the actual speed of e-bikes (Petzoldt et al 2017), and because of the rise in traffic conflicts with other road users (Huertas-Leyva et al 2018). Consequently, cyclists on e-bikes need to perform avoidance manoeuvres more frequently than those riding conventional pedal bicycles (Dozza and Bianchi Piccinini 2014).…”