Introduction
In this lesson, we learned about rigid bodies in Maya. Rigid bodies can be characterized in two different ways: a passive rigid body and an active rigid body. An active rigid body is reactive to dynamics and collisions – it moves, and is able to be collided with. A passive rigid body is able to be collided with, but does not move.
For example, imagine throwing a bouncy ball against a solid brick wall: the ball is an active rigid body because it moves through the air, hits the wall and bounces back. The wall is a passive rigid body as it gets hit by the ball, but does not move or change at all.
Rigid Body Bowling
Here is a basic example of a rigid bodies simulation that I created in Maya with some instruction from my tutor.
I started by creating a bowling alley with a polyplane and cubes. Then, I made a bowling ball by just re-sizing a sphere primitive. Next, I looked up orthographic images for bowling pins online, and used the orthographic views to model a bowling pin in Maya using a cylinder primitive and the extrude and scale functions. Once I had my first bowling pin, I duplicated it 10 times and arranged the clones in the 10-pin bowling triangle shape.
Now, I could make my objects into rigid bodies with gravity applied to them for my physics simulation. I selected all of my pins, and changed my interface from the modelling view to the FX view. From there, I went to the Fields/Solvers menu at the top of the screen and selected the tick box next to ‘create active rigid body’. This brought up a menu where I could change the properties of the active rigid body – I changed the mass of all of the pins to unit 2 so that they would be lighter than my bowling ball and fly into the air. I then repeated the same process but with the bowling ball, changing the mass to 10, so that it would hit the pins with a lot of force. After that, I selected my bowling alley and chose the option ‘create passive rigid body’ from the same Fields/Solvers menu, this time without clicking the tick box, as I didn’t want to change any of its attributes – I only needed a hard surface for the other objects to exist on.
Now, I applied gravity to the bowling ball by going to the Fields/Solvers menu again and clicking the tick box next to gravity. This brought up a menu where I could change the magnitude or intensity of the gravity as well as the direction of the object that I am applying gravity to. I changed the direction on the X axis to -10 because that was the direction my ball would have to go to in order to hit the pins. The magnitude was automatically set to 9.8 because that is the force of Earth’s gravity in m/s² – meaning that the objects being affected by this magnitude would behave in the same wat that they do on Earth, whereas if you changed the magnitude, the objects would behave as though they were in low gravity.
Playing the animation now gave me a simulation of the bowling ball knocking into the pins.