Unigine.JointWheel Class
| Inherits from: | Joint |
This class is used to create ray-cast wheels. Both a frame and a wheel are rigid bodies. There is no need to assign a shape to the wheel: ray casting is used to detect collision of the wheel with a surface.
Example#
The following code illustrates connection of two rigid bodies (frame and wheel) using a wheel joint.
Source code (C#)
JointWheel joint = new JointWheel(frame, wheel);
// setting joint anchor coordinates
joint.WorldAnchor = wheel.Object.WorldTransform * new dvec3(0.0f));
// setting joint axes coordinates
joint.WorldAxis0 = new vec3(0.0f,0.0f,1.0f);
joint.WorldAxis1 = new vec3(0.0f,1.0f,0.0f);
// setting linear damping and spring rigidity
joint.LinearDamping = 200.0f;
joint.LinearSpring = 100.0f;
// setting lower and upper suspension ride limits [-1.0; 0.0]
joint.LinearLimitFrom = -1.0f;
joint.LinearLimitTo = 0.0f;
// setting target suspension height
joint.LinearDistance = 0.5f;
// setting maximum angular velocity and torque
joint.AngularVelocity = -20.0f;
joint.AngularTorque = 10.0f;
// setting wheel parameters
joint.WheelRadius = 0.5f;
joint.WheelMass = 4.0f;
joint.WheelThreshold = 0.1f;
// setting tyre friction parameters
joint.TangentFriction = 4.0f;
joint.BinormalFriction = 5.0f;
// setting number of iterations
joint.NumIterations = 8;See Also#
- Creating a Car with Wheel Joints usage example.
- UnigineScript API sample <UnigineSDK>/data/samples/joints/wheel_00
- UnigineScript API sample <UnigineSDK>/data/samples/physics/car_02
JointWheel Class
Properties
float CurrentSlipRatio#
The current ratio of wheel spin to ground speed.
float CurrentSlipAngle#
The current angle between the wheel direction and the frame direction.
float WheelThreshold#
The threshold difference between the wheel and ground velocities. when it is too small, the longitudinal force will be scaled down to prevent unnatural vibrations.
float WheelRadius#
The radius of the attached wheel.
float WheelMass#
The mass of the attached wheel.
Notice
If g (Earth's gravity) equals to 9.8 m/s
2, and 1 unit equals to 1 m, the mass is measured in kilograms.
float TangentFriction#
The longitudinal (forward) friction of the tire.
float TangentAngle#
The coefficient specifying how fast the optimal longitudinal force can be achieved. the larger this value, the more is the impulse produced by the tire.
float BinormalFriction#
The lateral (sideways) friction of the tire.
float BinormalAngle#
The coefficient specifying how fast the optimal lateral force can be achieved. the larger this value, the more is the impulse produced by the tire.
float CurrentAngularVelocity#
The current rotation velocity of the attached wheels.
float AngularVelocity#
The target velocity of wheel rotation.
float AngularTorque#
The maximum torque of the attached angular motor.
float AngularDamping#
The angular damping of the joint (wheel rotation damping).
float CurrentLinearDistance#
The current suspension compression (i.e. the length of the suspension).
float LinearSpring#
The rigidity coefficient of the suspension.
float LinearLimitTo#
The high limit of the suspension ride.
float LinearLimitFrom#
The low limit of the suspension ride.
float LinearDistance#
The target height of the suspension.
float LinearDamping#
The linear damping of the suspension.
int PhysicsIntersectionMask#
The A physics intersection mask of the joint.
vec3 WorldAxis1#
The wheel spindle axis in the world coordinates.
vec3 WorldAxis0#
The suspension axis in the world coordinates.
vec3 Axis11#
The wheel spindle in coordinates of the wheel (body 1).
vec3 Axis10#
The wheel spindle axis in coordinates of the frame (body 0).
vec3 Axis00#
The Suspension axis coordinates.
Members
JointWheel ( ) #
Constructor. Creates a wheel joint with an anchor at the origin of the world coordinates.JointWheel ( Body body0, Body body1 ) #
Constructor. Creates a wheel joint connecting two given bodies. An anchor is placed between centers of mass of the bodies.Arguments
- Body body0 - Frame to be connected with the joint.
- Body body1 - Wheel to be connected with the joint.
JointWheel ( Body body0, Body body1, vec3 anchor, vec3 axis0, vec3 axis1 ) #
Constructor. Creates a wheel joint connecting two given bodies with specified suspension and spindle axis coordinates and an anchor placed at specified coordinates.Arguments
- Body body0 - Frame to be connected with the joint.
- Body body1 - Wheel to be connected with the joint.
- vec3 anchor - Anchor coordinates.
- vec3 axis0 - Suspension axis coordinates.
- vec3 axis1 - Wheel spindle axis coordinates.
vec3 GetContactNormal ( ) #
Returns a normal of a point of contact with the ground, in world coordinates.Return value
Normal.Object GetContactObject ( ) #
Returns an object representing the ground.Return value
Ground object.vec3 GetContactPoint ( ) #
Returns a point of contact with the ground, in world coordinates.Return value
Point coordinates.Shape GetContactShape ( ) #
Returns a shape of the object representing the ground.Return value
Shape of the ground object.int GetContactSurface ( ) #
Returns a surface of a ground object, which is in contact.Return value
Surface number.Last update:
2022-12-14
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