I've continued implementing various types of actuators since Saturday. The list is now including the following:
1. Motor: It does what it sounds like, consisting of a base an output shaft that has a torque applied to it.
2. Thruster: Also does what it sounds like, applying a force to itself along its vertical axis.
3. Linear Actuator: Acts like a hydraulic or pneumatic cylinder. It consists of two rectangular bodies that apply forces to push together or away from each other. These also have limits for how far the bodies can travel relative to each other.
4. Power Joint: Similar to the linear actuator except as a rotational case. This one can be thought of as an elbow.
The actuators all share a similar interface to control the percentage of the output that is applied for each type. They still serve as relatively simple machines, but it has been fun playing around with them once they have been implemented. Currently I'm trying to figure out why the power joint bounces around when it's either fully extended or fully retracted - I think it has to do with both bodies laying flat on the ground and the dynamics solver is having issues dealing with all of the contact surface. I'm sure I'll figure it out, but I need to experiment a little more. Here's a couple screen shots showing extended and retracted (next to the same cart from last time)...
