Dynamic Body Simulation
Simulation is a super useful tool to have as a complement to the familiar FEA. For non-static mechanical systems, simulation is a must to get a starting point for load conditions for FEA. Of course, as with any simulation, it is important to validate the results with experimental data.
Sensor Placement
In MuJoCo, where the sensor is placed is very important. To fully understand how the XML affects the sensor reading, I dug into the documentation and empirically validated with a simple test setup.
Physical Sanity Check
To sanity check the simulation, I got the readings from when it goes into a static state with results from free body diagram calculations. It's always good practice to do some on-paper calculations to verify simulation.
Collected Data on Robot
An example of using this dynamic body simulation: getting the forces on one of the idle side of the upper leg during a fall to determine if this part can be switched to nylon to reduce weight. The plots show the force experienced during the fall.