webots - Vehicle modelisation on WeBots

Question

I would like to know how the vehicle's objects are modeled in WeBots and its dynamics equations. I know that two types of control can be used: using cruising speed, with targets a final velocity but with a constant acceleration (proportional to the time0to100 value in the PROTO file), and using the throttle which controls the torque of the vehicle.

Since I want to control the vehicle with a controller at high frequencies, the only option to realistically emulate a real vehicle is the torque control. But to predict the behavior of the vehicle in this case I need to know how the torque is calculated, the transmission equations and the how all of this is implemented with ODE. I read the Car and Driver library pages and both of then had some details and descriptions about how the system works, but these explanations wasn't detailed enough. I would also like to understand how the interaction between tires and asphalt is modeled.

Thanks,

标签： webots

Answer 1

扭矩控制确实是最现实的选择。

关于方程，这里详细描述了各种发动机模型：https ://www.cyberbotics.com/doc/automobile/driver-library#engine-models

此外，变速箱和阿克曼机构用于将扭矩从电机转换/传输到两轮/四轮，这没有记录，但代码可在此处访问（部分特定于车辆）： https://github。 com/omichel/webots/blob/master/projects/default/libraries/vehicle/c/driver/src/driver.c#

特别是引擎模型+传输在这里实现： https ://github.com/omichel/webots/blob/master/projects/default/libraries/vehicle/c/driver/src/driver.c#L126

然后在 2/4wheels 之间拆分： https ://github.com/omichel/webots/blob/master/projects/default/libraries/vehicle/c/driver/src/driver.c#L299

关于轮胎和沥青之间的相互作用，这被定义为 Webots 中的常规接触属性（然后用于创建 ODE 接触接头：http ://ode.org/wiki/index.php?title=Manual#Contact ）：

https://www.cyberbotics.com/doc/reference/contactproperties