hmi.physics
Class Mass

java.lang.Object
  hmi.physics.Mass

Direct Known Subclasses:

OdeMass

public abstract class Mass
extends Object

Constructor Summary

Mass()

Method Summary

void	addMass(Mass m, float[] p1, float[] p2, float[] newPos) Combines with another Mass object.
abstract void	adjustMass(float newMass) Adjust the mass to be newMass (in kg)
abstract Mass	copy()
abstract void	getCOM(float[] c) Get the center of mass
abstract void	getInertiaTensor(float[] I) Get the inertia tensor
abstract float	getMass() Get the mass (in kg)
abstract void	rotate(float[] q) Rotates the inertia tensor
void	scale(float s) Uniform scale Assumes that the Mass objects has it COM at (0,0,0) and that the density is uniform.
void	scale(float[] s) Non-uniform scale Assumes that the Mass objects has it COM at (0,0,0) and that the density is uniform.
abstract void	setCOM(float[] c) Sets the center of mass
abstract void	setFromBox(float[] size, float density) Set a new box mass, assumes center at (0,0,0)
abstract void	setFromCapsule(float radius, float height, int direction, float density) Set a capsule mass, assume center = CoM at (0,0,0)
abstract void	setFromGMesh(GMesh m, float density) Set mass properties on the basis of a closed GMesh, assumes uniform density density is set in kg/m3 (or mass unit/length unit^3)
abstract void	setFromSphere(float radius, float density) Set a sphere-shaped mass, assume center at (0,0,0)
abstract void	setInertiaTensor(float[] I) Sets the inertia tensor
abstract String	toString() String representation
void	translate(float[] pos)
abstract void	translate(float x, float y, float z) Translates the COM and inertia tensor

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Mass

public Mass()

Method Detail

getCOM

public abstract void getCOM(float[] c)

Get the center of mass

getInertiaTensor

public abstract void getInertiaTensor(float[] I)

Get the inertia tensor

setCOM

public abstract void setCOM(float[] c)

Sets the center of mass

setInertiaTensor

public abstract void setInertiaTensor(float[] I)

Sets the inertia tensor

getMass

public abstract float getMass()

Get the mass (in kg)

Returns:

the mass

adjustMass

public abstract void adjustMass(float newMass)

Adjust the mass to be newMass (in kg)

Parameters:

newMass - the new mass

translate

public abstract void translate(float x,
                               float y,
                               float z)

Translates the COM and inertia tensor

translate

public void translate(float[] pos)

rotate

public abstract void rotate(float[] q)

Rotates the inertia tensor

Parameters:

q - rotation as quaternion

setFromBox

public abstract void setFromBox(float[] size,
                                float density)

Set a new box mass, assumes center at (0,0,0)

Parameters:

size - of the sides of the box

density - the density of the box

setFromSphere

public abstract void setFromSphere(float radius,
                                   float density)

Set a sphere-shaped mass, assume center at (0,0,0)

Parameters:

radius - radius of the sphere

density - density of the sphere

setFromCapsule

public abstract void setFromCapsule(float radius,
                                    float height,
                                    int direction,
                                    float density)

Set a capsule mass, assume center = CoM at (0,0,0)

Parameters:

radius - radius of the spheres and cylinder

height - height of the cylinder

direction - direction of the long axes of the cylinder: 1=x, 2=y, 3=z

density - density

setFromGMesh

public abstract void setFromGMesh(GMesh m,
                                  float density)

Set mass properties on the basis of a closed GMesh, assumes uniform density density is set in kg/m3 (or mass unit/length unit^3)

toString

public abstract String toString()

String representation

Overrides:

toString in class Object

copy

public abstract Mass copy()

scale

public void scale(float[] s)

Non-uniform scale Assumes that the Mass objects has it COM at (0,0,0) and that the density is uniform.

Parameters:

s - scale vector [sx,sy,sz]

scale

public void scale(float s)

Uniform scale Assumes that the Mass objects has it COM at (0,0,0) and that the density is uniform.

Parameters:

s - the desired acale

addMass

public void addMass(Mass m,
                    float[] p1,
                    float[] p2,
                    float[] newPos)

Combines with another Mass object. Assumes that both Mass objects have their local COM at (0,0,0) p1 and p2 indicated the COM of this Mass object and the Mass object to add in world coordinates The new position of the COM in world coordinates is returned in newPos This Mass object will be translated so that its local center is again at (0,0,0)

Parameters:

m - mass to add

p1 - position of this mass object in world coordinates

p2 - position of m in world coordinates

newPos - output: new COM in world coordinates of the combined mass, cannot be aliased to p1 or p2