JointWheel Class
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.
JointWheel Class
Members
JointWheel ()
Constructor. Creates a wheel joint with an anchor at the origin of the world coordinates.JointWheel (const Ptr<Body> & body0, const Ptr<Body> & body1)
Constructor. Creates a wheel joint connecting two given bodies. An anchor is placed between centers of mass of the bodies.Arguments
- const Ptr<Body> & body0 - The wheel to connect with the joint.
- const Ptr<Body> & body1 - The frame to connect with the joint.
JointWheel (const Ptr<Body> & body0, const Ptr<Body> & body1, const Math::Vec3 & anchor, const Math::vec3 & axis0, const Math::vec3 & axis1)
Arguments
- const Ptr<Body> & body0
- const Ptr<Body> & body1
- const Math::Vec3 & anchor
- const Math::vec3 & axis0
- const Math::vec3 & axis1
float getAngularTorque ()
Returns the maximum torque of the attached angular motor.Return value
Maximum torque.float getAngularDamping ()
Returns the angular damping of the joint (wheel rotation damping).Return value
Angular damping.void setAxis11 (const Math::vec3 & axis11)
Sets a suspension axis in coordinates of the frame: an axis around which a wheel rotates when steering.Arguments
- const Math::vec3 & axis11 - Suspension axis in coordinates of the frame.
float getAngularVelocity ()
Returns the target velocity of wheel rotation.Return value
Target velocity in radians per second.Ptr<Shape> getContactShape ()
Returns a shape of the object representing the ground.Return value
Shape of the ground object.void setWorldAxis1 (const Math::vec3 & axis1)
Sets a suspension axis in the world coordinates.Arguments
- const Math::vec3 & axis1 - Suspension axis in the world coordinates.
float getLinearDamping ()
Returns the linear damping of the suspension.Return value
Linear damping.void setLinearLimitTo (float to)
Sets a high limit of the suspension ride.Arguments
- float to - Limit in units.
float getLinearSpring ()
Returns the rigidity coefficient of the suspension.Return value
Rigidity coefficient.float getCurrentLinearDistance ()
Returns the current suspension compression (i.e. the length of the suspension).Return value
Current suspension length in units.void setTangentAngle (float angle)
Sets a coefficient specifying how fast the optimal longitudinal force can be achieved. The larger this value, the more is the impulse produced by the tire.Arguments
- float angle - Coefficient characterizing the tire longitudinal impulse. If a negative value is provided, 0 will be used instead.
void setWheelMass (float mass)
Sets a mass of the attached wheel.Notice
If g (Earth's gravity) equals to 9.8 m/s2, and 1 unit equals to 1 m, the mass is measured in kilograms.
Arguments
- float mass - Mass of the wheel. If a negative value is provided, 0 will be used instead.
Math::vec3 getAxis00 ()
Returns the wheel axis. This is a wheel spindle.Return value
Wheel axis.Ptr<Object> getContactObject ()
Returns an object representing the ground.Return value
Ground object.void setAngularVelocity (float velocity)
Sets a maximum velocity of wheel rotation.Arguments
- float velocity - Velocity in radians per second.
void setTangentFriction (float friction)
Sets a longitudinal (forward) friction of the tire.Arguments
- float friction - Longitudinal friction. If a negative value is provided, 0 will be used instead.
void setBinormalAngle (float angle)
Sets a coefficient specifying how fast the optimal lateral force can be achieved. The larger this value, the more is the impulse produced by the tire.Arguments
- float angle - Coefficient characterizing the tire lateral impulse. If a negative value is provided, 0 will be used instead.
Math::vec3 getContactNormal ()
Returns a normal of a point of contact with the ground, in world coordinates.Return value
Normal.float getLinearLimitTo ()
Returns the high limit of the suspension ride.Return value
High limit in units.float getLinearLimitFrom ()
Returns the low limit of the suspension ride.Return value
Low limit in units.void setCurrentAngularVelocity (float velocity)
Sets the rotation velocity for the attached wheels. For example, it allows to reset it to zero and stop the car when necessary.Arguments
- float velocity - Angular velocity in radians per second.
void setLinearDamping (float damping)
Sets a linear damping of the suspension.Arguments
- float damping - Linear damping. If a negative value is provided, 0 will be used instead.
Math::Vec3 getContactPoint ()
Returns a point of contact with the ground, in world coordinates.Return value
Point coordinates.void setLinearDistance (float distance)
Sets a target height of the suspension.Arguments
- float distance - Height in units.
void setBinormalFriction (float friction)
Sets a lateral (sideways) friction of the tire.Arguments
- float friction - Lateral friction. If a negative value is provided, 0 will be used instead.
Math::vec3 getWorldAxis1 ()
Returns the suspension axis in the world coordinates.Return value
Suspension axis in the world coordinates.float getWheelRadius ()
Returns the radius of the attached wheel.Return value
Radius of the wheel in units.float getWheelWidth ()
Returns the width of the attached wheel.Return value
Width of the wheel in units.void setLinearSpring (float spring)
Sets a rigidity coefficient of the suspension.Arguments
- float spring - Rigidity coefficient. If a negative value is provided, 0 will be used instead.
void setWorldAxis0 (const Math::vec3 & axis0)
Sets a wheel axis in the world coordinates. This is a wheel spindle.Arguments
- const Math::vec3 & axis0 - Wheel axis in the world coordinates.
float getWheelMass ()
Returns the mass of the attached wheel.Notice
If g (Earth's gravity) equals to 9.8 m/s2, and 1 unit equals to 1 m, the mass is measured in kilograms.
Return value
Mass of the wheel.void setAxis10 (const Math::vec3 & axis10)
Sets a suspension axis in coordinates of the wheel: an axis around which a wheel rotates when moving forward (or backward).Arguments
- const Math::vec3 & axis10 - Suspension axis in coordinates of the wheel.
Math::vec3 getAxis10 ()
Returns the suspension axis in coordinates of the wheel.Return value
Suspension axis in coordinates of the wheel.float getTangentFriction ()
Returns the longitudinal (forward) friction of the tire.Return value
Longitudinal friction.void setAngularDamping (float damping)
Sets an angular damping of the joint (wheel rotation damping).Arguments
- float damping - Angular damping. If a negative value is provided, 0 will be used instead.
void setWheelWidth (float width)
Sets a width of the attached wheel.Arguments
- float width - Width of the wheel in units. If a negative value is provided, 0 will be used instead.
float getWheelThreshold ()
Returns 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.Return value
Difference threshold.float getLinearDistance ()
Returns the target height of the suspension.Return value
Target height in units.void setAngularTorque (float torque)
Sets a maximum torque of the attached angular motor.Arguments
- float torque - Maximum torque. If a negative value is provided, 0 will be used instead.
void setWheelRadius (float radius)
Sets a radius of the attached wheel.Arguments
- float radius - Radius of the wheel in units. If a negative value is provided, 0 will be used instead.
float getBinormalAngle ()
Returns 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.Return value
Coefficient characterizing the tire lateral impulse.void setWheelThreshold (float threshold)
Sets a threshold difference between the wheel and ground velocities. When it is too small, the longitudinal force will be scaled down to prevent unnatural vibrations.Arguments
- float threshold - Difference threshold. If a negative value is provided, 0 will be used instead.
Math::vec3 getWorldAxis0 ()
Returns the wheel axis in the world coordinates. This is a wheel spindle.Return value
Wheel axis in the world coordinates.float getCurrentSlipRatio ()
Returns the current ratio of wheel spin to ground speed.Return value
Current slip ratio in percents. 0 means that the velocities are equal. If the throttle is pressed, the value will be positive. If the brake is pressed, the value will be negative.float getTangentAngle ()
Returns 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.Return value
Coefficient characterizing the tire longitudinal impulse.void setCurrentLinearDistance (float distance)
Sets suspension compression (i.e. the length of the suspension).Arguments
- float distance - Suspension length in units.
int getContactSurface ()
Returns a surface of a ground object, which is in contact.Return value
Surface number.float getCurrentAngularVelocity ()
Returns the current rotation velocity of the attached wheels.Return value
Current angular velocity in radians per second.Math::vec3 getAxis11 ()
Returns the suspension axis in coordinates of the frame.Return value
Suspension axis in coordinates of the frame.int getIntersectionMask ()
Returns an intersection mask of the joint.Return value
Integer, each bit of which is a mask.float getCurrentSlipAngle ()
Returns the current angle between the wheel direction and the frame direction.Return value
Current slip angle in degrees.void setIntersectionMask (int mask)
Sets an intersection mask for the joint.Arguments
- int mask - Integer, each bit of which is a mask.
float getBinormalFriction ()
Returns the lateral (sideways) friction of the tire.Return value
Lateral friction.void setAxis00 (const Math::vec3 & axis00)
Sets a wheel axis along which a wheel moves linearly. This is a shock absorber.Arguments
- const Math::vec3 & axis00 - Wheel axis.
void setLinearLimitFrom (float from)
Sets a low limit of the suspension ride.Arguments
- float from - Limit in units.
Last update: 2017-07-03
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