School of Mechanical Engineering, The University of Adelaide, Adelaide, SA, 5005, Australia.
College of Health and Life Sciences, Hamad Bin Khalifa University, Doha, Qatar.
Sci Rep. 2022 Jul 5;12(1):11356. doi: 10.1038/s41598-022-15384-3.
A series of measurements taken with two instrumented track bicycles in a velodrome are presented. The bicycle wheel speed, cadence, roll angle, steering angle, power, and airspeed are recorded. The experimentally-measured values are compared to existing theoretical models of roll and steering angles. The accuracy of the roll angle calculations is dependent on the fidelity of the modelled cyclist path and decreases for higher riding speeds. Experimental measurements of the steering angle show a reasonable agreement to theoretical calculations, albeit with reduced steering angles on the bends at higher speeds. There is also seen an increasing steering angle oscillation within each pedal cycle with increasing bicycle velocity which may influence a cyclist's rolling resistance and the aerodynamic flow around the bicycle's front end. Observations are made of changes in the flow field ahead of the bicycle due to the presence of other riders on the track, showing an effective tailwind of up to 0.7 m/s. The measured power shows a decrease at the bend entry due to the changing roll angle. Data presented in this paper provides new insights and can help to provide a validation of values used in existing track cycling analytic models.
本文呈现了在室内赛车场使用两辆装有仪器的赛车进行的一系列测量。记录了自行车轮速、踏频、滚转角、转向角、功率和空速。将实验测量值与现有的滚转角和转向角理论模型进行了比较。滚转角计算的准确性取决于所建模的自行车路径的逼真度，并且在更高的骑行速度下准确性会降低。转向角的实验测量结果与理论计算结果吻合较好，但在较高速度下弯道处的转向角会减小。随着自行车速度的增加，每个踏周期内的转向角振荡也会增加，这可能会影响自行车的滚动阻力和自行车前端的空气流动。观察到由于赛道上其他车手的存在，自行车前方流场的变化，显示出有效顺风可达 0.7 m/s。由于滚转角的变化，在弯道入口处测量到的功率会下降。本文提供的数据提供了新的见解，并有助于验证现有的场地自行车分析模型中使用的值。
