Earth
Theme: Panzerkampf
Vehicles limited to move along or slightly above some form of surface. Classified by what is used to apply steering and drive forces against the ground.
Wheeled
Bicycles, motorcycles, cars, trucks, buses and everything else with wheels. Wagons :). There are two way to create these, with constraints or with a vehicle controller.
Constraints
Wheels are created as rigid bodies and then constrained to the vehicle body. The type of wheels is fixed wheels, suspension wheels and steering wheels.
Fixed:
Suspension:
Steering:
Vehicle controller
This is a component of a physic system that fake the wheels of a rigidbody with raycasts. Details about how it works are on the vehicle controller page.
Tracked
For a tracked vehicle only the road wheels need to be simulated. The track and the other wheels can then be run only as a visual model. All wheels should be the same size and place in a line. To turn drive the wheels on one side faster. A vehicle controller can be used for this.
Railed
Stable Rollers - Numberphile - 2017
The Physics of Disaster: An Exploration of Train Derailments - 2013
Grip of the train wheels - 2012
Bullet train -2012
Modeling a train using joints & a number of raycast vehicles - 2011
surface-physics - 2011
Adhesion railway - 2005
Steam vs Diesel - 1998
Wheels and Bogies - 1998
Skied
Hovercraft
A hovercraft is made up of two parts, the lift and the thrust. The lift keep the craft above ground and the thrust moves and turns it.
Hovercraft physics package manual - 2014
Mech