2025-06-10 Static Torque in EPS

In the context of Electric Power Steering (EPS) systems, “static torque” refers to the torque required to maintain the steering wheel's position when the vehicle is stationary or moving slowly, and no external forces are being applied to the steering. It's essentially the resistance a driver feels when holding the steering wheel still, and is a crucial component in the design of assist characteristics.
在電動輔助轉向 (EPS) 系統中，「靜態扭力」是指當車輛靜止或緩慢行駛且沒有外力作用於方向盤時，保持方向盤位置所需的扭矩。它本質上是駕駛者握住方向盤時所感受到的阻力，是輔助特性設計中的重要組成部分。

Here's a more detailed breakdown:

了解 EPS 中的靜態扭矩：
Holding Torque: Similar to a stepper motor's holding torque, static torque is the force required to hold the steering wheel in place against the internal friction and external forces.
保持扭力：與步進馬達的保持扭矩類似，靜態扭矩是抵抗內部摩擦和外力將方向盤固定到位所需的力。
Assist Characteristics: The EPS system provides assistance to the driver in turning the steering wheel. The level of assistance, and thus the static torque, is influenced by factors like steering wheel angle, speed, and driving conditions.
輔助特性：EPS 系統為駕駛轉動方向盤提供輔助。助力大小以及靜態扭力會受到方向盤角度、車速和駕駛條件等因素的影響。
Driver Feel: A properly designed static torque profile contributes to a natural steering feel for the driver, making it easier to maneuver the vehicle and park.
駕駛感受：

合理設計的靜態扭矩曲線有助於為駕駛員提供自然的轉向感覺，使操縱車輛和停車變得更容易。

2.靜態轉向扭矩的組成：
Tire-Patch Sliding Torque: The torque generated by the friction between the tires and the road surface when the vehicle is turning.
輪胎補丁滑動扭矩：車輛轉彎時輪胎與路面摩擦所產生的扭力。
Gravity Aligning Torque: The torque exerted by gravity on the steering system, especially when the vehicle is on a slope.
重力調心扭力：重力對轉向系統施加的扭矩，尤其是當車輛在斜坡上時。
Internal Friction Torque: The torque caused by friction within the steering system itself (e.g., gears, linkages).
內部摩擦扭矩：轉向系統本身（例如齒輪、連桿）內的摩擦所造成的扭力。

3. EPS中靜扭矩的重要性：
Parking and Low-Speed Maneuvering: Static torque is particularly important when parking and performing low-speed maneuvers where the driver needs a smooth and controlled steering feel.
停車和低速操縱：當停車和低速駕駛時，靜態扭力尤其重要，因為駕駛者需要平穩、可控的轉向感覺。
Driver Comfort: The static torque should be designed to provide an appropriate level of assistance, reducing the effort required by the driver while maintaining a natural feel.
駕駛舒適度：靜態扭力的設計應提供適當程度的輔助，減少駕駛者所需的努力，同時保持自然的感覺。
System Stability: A well-controlled static torque helps ensure the stability of the steering system, especially at low speeds.
系統穩定性：控制良好的靜態扭矩有助於確保轉向系統的穩定性，尤其是在低速時。