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我正在尝试根据以下教程制作车轮对撞机 PID 控制器：

https://www.habrador.com/tutorials/pid-controller/1-car-follow-path/

我对 FixedUpdate 方法进行了修订，以根据与样条航路点的角度差（如果在脚本中实例化一个）来修改转向方向，并尝试根据汽车的速度引入“滑行”或“制动”行为正在走，转弯的角度有多紧。目前，“漂移”将车轮摩擦曲线设置为车轮之间交替的前向和侧向摩擦刚度值。通常，任何汽车在车轮碰撞器上的侧向刚度系数为 2，如下所示：

在此处输入图像描述

现在，问题是，很难在理想的 PID 控制器设置和预期阈值之间找到平衡点 1.）由于转向角可能失控而导致制动或滑行 2.）当两者之间即将出现角度时“漂移”汽车前方的下一个航路点为汽车转弯提供了一个狭窄的角度。

这是我当前的 PID 值，老实说，我已经对这些值进行了相当多的调整（我知道这在某种程度上是可以预期的）：

在此处输入图像描述

这是相关代码 - FixedUpdate 循环：

void FixedUpdate()
    {
        float motor = carControl.maxForwardTorque;

        //Manual controls for debugging
        //float motor = carControl.maxForwardTorque * im.throttle;
        //float steering = carControl.maxTurn * im.steer;

        //
        //Calculate the steering angle
        //
        //The simple but less accurate way -> will produce drunk behavior
        //float steeringAngle = maxSteeringAngle * Math.SteerDirection(transform, steerPosition, currentWaypoint);

        //Get the cross track error, which is what we want to minimize with the pid controller
        float CTE = AIVehicleMath.GetCrossTrackError(steerPosition, previousWaypoint, currentWaypoint);

        //But we still need a direction to steer
        if(splineWalker)
            CTE *= AIVehicleMath.SteerDirection(transform, steerPosition, splineWalker.transform.position);
        else
            CTE *= AIVehicleMath.SteerDirection(transform, steerPosition, currentWaypoint);

        float steeringAngle = PIDControllerScript.GetSteerFactorFromPIDController(CTE);

        //Limit the steering angle
        steeringAngle = Mathf.Clamp(steeringAngle, -carControl.maxTurn, carControl.maxTurn);

        //Average the steering angles to simulate the time it takes to turn the steering wheel
        float averageAmount = 30f;

        averageSteeringAngle = averageSteeringAngle + ((steeringAngle - averageSteeringAngle) / averageAmount);

        Debug.Log("Average steering angle is " + averageSteeringAngle);

        //
        //Apply everything to the car 
        //
        float signFactor = averageSteeringAngle/carControl.maxTurn;

        im.steer = signFactor;
        if (Mathf.Abs(averageSteeringAngle) > 15 && rb.velocity.magnitude > 15)
        {
            im.throttle = 0;
            im.brake = true;
        }
        else if (Mathf.Abs(averageSteeringAngle) > 5 && rb.velocity.magnitude > 15)
        {
            im.throttle = 0;
            im.brake = false;
        }
        else
        {
            im.throttle = 1;
            im.brake = false;
        }

        float currDistFromWP = Vector3.Distance(transform.position, allWaypoints[currentWaypointIndex].position);

        float speed = rb.velocity.magnitude;
        float timeFloatLeft = currDistFromWP / speed;

        Vector3 nextVector;
        Transform nodeA;
        Transform nodeB;
        if (currentWaypointIndex == allWaypoints.Count - 1)
        {
            nodeA = allWaypoints[currentWaypointIndex];
            nodeB = allWaypoints[0];
        }
        else
        {
            nodeA = allWaypoints[currentWaypointIndex];
            nodeB = allWaypoints[currentWaypointIndex + 1];
        }
        float distanceBetweenNextTwo = Vector3.Distance(nodeA.position, nodeB.position);
        float angleBetweenTwo = Vector3.Angle(transform.position, nodeB.position);

        if (currDistFromWP < 20 && angleBetweenTwo > 30)
            im.drift = true;
        else
            im.drift = false;
    }

任何人都可以就我如何更有效地解决这个问题提出建议，也许？不管我做什么，即使我将速度限制在 10 或 20 的超慢速度，汽车也会继续以醉酒的方式转动。当然，想象汽车以 70 或 90 的速度行驶！事实证明，现在有点头疼。

感谢任何建议或意见。再次感谢。

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