joint_position_controller example world behaves differently in dartsim, bullet*

[scpeters]

Environment

• OS Version: macOS: 13.5.2-x86_64
• Source or binary build? binary build of harmonic prereleases 8.0.0~pre1_3

Description

• Expected behavior: when I launch examples/worlds/joint_position_controller.sdf with different physics engines and publish different reference commands, the model responds at very different rates for each physics engine
• Actual behavior: they should respond in a similar way (similar velocity profiles, time to reach target position, etc)

Related to gazebosim/gz-physics#545.

Steps to reproduce

1. Launch gz-sim server with dartsim: gz sim -v 4 joint_position_controller.sdf -s --physics-engine gz-physics-dartsim-plugin
2. Launch gz-sim gui: gz sim -v 4 -g, zoom in and view wireframe
3. Publish positon target: gz topic -t "/rotor_cmd" -m gz.msgs.Double -p "data: 9.0"
4. Unpause and observe how long it takes to stop spinning (about 3 seconds)
5. Repeat 1-4 for gz-physics-bullet-featherstone-plugin (about 0.5 s) and gz-physics-bullet-plugin (still spinning after 10 seconds)

Output