Motorcycle designers aim to enhance vehicle performance, stability, and safety, especially when the vehicle is approaching the tyres' friction limit. A strategy to achieve these purposes is to design All-Wheel Drive (AWD) vehicles with active torque distribution. Nowadays, effective technical solutions for powering the front wheel of a motorcycle have been proposed. The use of traction on both front and rear wheel is convenient when tyre friction is low, enhancing vehicle safety and performance. In this context, this paper presents a sensorless, open-loop traction strategy for AWD motorcycles that improves performance and stability both in straight running and in cornering, without requiring the knowledge of road-tyre adherence. This novel traction distribution strategy is based on the idea of maximising the area of the motorcycle performance envelope, also known as g-g diagram. A simplified mathematical model is used to find closed-form solution to this problem, then converted into a control algorithm for the front and rear driving torques. The performance of the proposed method is assessed with simulations: a detailed model of a light electric motorcycle is used for calculating the non-linear vehicle performance envelope, the acceleration response in straight running and cornering, and the response to road irregularities. Moreover, a comparison with feedback slip-based traction control system is conducted. Simulation results indicate that the AWD motorcycle outperforms the conventional rear wheel drive motorbike almost in all situations, especially when road-tyre adherence is low, and that no counter-indication for the adoption of the AWD architecture exists.

摩托车设计师旨在提高车辆性能、稳定性和安全性，尤其是在车辆接近轮胎摩擦极限时。实现这些目的的策略是设计具有主动扭矩分配的全轮驱动 (AWD) 车辆。目前，已经提出了为摩托车前轮提供动力的有效技术方案。在轮胎摩擦力较低的情况下，前后轮都可以方便地使用牵引力，从而提高车辆的安全性和性能。在此背景下，本文提出了一种用于 AWD 摩托车的无传感器开环牵引策略，该策略可提高直线行驶和转弯时的性能和稳定性，而无需了解道路轮胎的附着力。这种新颖的牵引力分配策略是基于最大化摩托车性能包络面积的想法，也称为 gg 图。一个简化的数学模型被用来找到这个问题的封闭形式的解决方案，然后转化为一个控制算法的前后驱动扭矩。通过仿真评估所提出方法的性能：使用轻型电动摩托车的详细模型来计算非线性车辆性能包络线、直线行驶和转弯时的加速度响应以及对道路不规则性的响应。此外，与基于反馈打滑的牵引力控制系统进行了比较。仿真结果表明，AWD 摩托车几乎在所有情况下都优于传统的后轮驱动摩托车，