Some ideas:
- You can use the Variable Mass blocks to add/remove soil from buckets (example: General Variable Mass block)
- You can use External Force and Torque block to apply the resistance force for a bucket digging through the ground.
- The Spatial Contact Force block can be used to model contact between the wheels and the ground. You'll have to either set the contact parameters to be very soft and/or add some additional forces to capture the effect of a deformable surface (move the ground plane, more resistance on the wheels).
There are discrete element modeling tools, such as EDEM, that can be combined with Simscape Multibody to model soil-tool interaction with much more detail, but these models will take significantly longer to simulate.
--Steve
