Material Properties

The material of body can be changed to simulate different kind of objects in nature. You can set material as one of defualt material sets at top of panel shown in screenshot below or you can set properties manually to fine tune body.

To Edit Material of Body:

1. select body

2. right click to get popup menu ,

3. now select edit body, which displays body properties dialog box.

4. Now click Material tab, now the window looks like ..

Making Body Global Attractor:

The attraction factor G shown above in figure behaves as Gravitational constant in calculation of Newtons Law of gravity, which is applied on each object by this body.

Setting G negative makes body repel each other following newton inverse square’s law of gravitation.

This is particularly useful to demonstrate planetary motion/solar system.

Key Controllars

The motion of body in simulation can be controlled by keyboard by assigning key controllers to the body

To Assign Key Controllers to Body:

1. select body

2. right click to get popup menu ,

3. now select edit body, which displays body properties dialog box.

4. Now click Controllers tab, now the window looks like ..

How the force/torque are applied:

When key is pressed Force/Torque is applied to body in each simulation step. On releasing key  force application ceases.

Force is calculated as product of mass and acceleration value associated with controller.

Torque is calculated as product of inertia and angular acceleration value associated with controller.

Collision Filtering

Collision filtering is used to only allow a category of bodies to collide with another category.

SimPhy provides very easy way to collision have a control over which category body may collide with which categories.

For this we need to set two properties of body in property panel (make sure body is selected)

1. Category    2. Collides with

Click on right cell adjacent to property to open category window as shown where you can edit category by checking and un-checking boxes.

Category:

Category is the groups to which body belongs,body may belong to  none,one or more category depending on checkboxes you tick.

Collides With:

You can assign the cetegory/group to which body can collide. Again there can be none,one or more category to whichbody will collide. No collision will take place(body will pass through) if body collides with body which is not there in collideswith group.

for example

if you set collideswith property to be none, body will not show any collision with any object.

if you set collideswith property to be all, body will show collision with every object.

if you set collideswith property to be AG, body will show collision with only those objects which have Group A or G in their category list.

Note:

Body1 and Body2 collide only when body1 collides with body2=true as well as body collides body1 is also true.

Or

In simple words body1 belongs to category collideswith of body2 and body2 belongs to category collideswith of body2.

Adding HTML Text to the body

The body can display text in HTML format, which is extremely useful to display information in simulation in eye catching/fancy way.

To Edit Text associated with Body:

1. select body

2. right click to get popup menu ,

3. now select edit body, which displays body properties dialog box.

4. Now click Edit.. beside Text Label to show html editor window as shown.