SOSML Parameter tuning

Tune the observers so they are working, compare with Frnaka estimates. SOSML is working as of #5 (closed), but is sensitive to certain parameter settings and not working very robust.

Goal: Have SOSML working, and maybe have less phase lag than the low-pass filter from standard momentum observer.

SOSML

• Test on two link in simulation
• Test on data from Franka Emika, either rosbag play or live data on Franka
  • Look at the contact transitions in detail

Observer, general

• Can do experiments with a higher-speed contact transition
• Ploting results:
  • Check timestamps on DOB estimate, could use the timestamp from the rosbag if needed
  • Frequency plot could help us see if there's internal filtering on the Franka estimate, but just need positive frequencies and log magnitude
• Check using SOSML intead of numerical differentiation once working
• Add UI to visualize observer results and robot motion
  • Set up ideal experiment environment
    • joint configuration to contact with FT sensor
    • contact trajectory profile
  • Debug check button reset
  • Identify & compensate joint friction effect
  • Add README file for manual of GUI
    • Don't set initial configuration too crouched. -> it may induce sudden jump when controller starts
    • Don't set joint P gain too high. 50 ~ 100 would be enough
  • Make icon images as qrc file
  • Plot joint pos/vel, EE Twist, EE Wrench
  • Integrate w/ MuJoCo, s.t. test can be done remotely.

Using measured joint torques?

• Add pseudoinverse times measured torques
• Add pseudoinverse times measured torques w/ inertial compensation
• [Kevin] Write up dynamics with joint flexibility and joint torque command vs real to compare effects of using measured torque

Experiment To Do Lists

• Test SOSML-based acceleration estimation to Task-space DOB and check its effect.
• Test with various velocity range for FRF analysis.
• Test using a compliance between robot and f/t sensor to stabilize the contact loss
• Online SOSML gain tuning by watching plots
  • Check during sinusoidal motion
• Plot velocity and evaluate if implementing friction model would be helpful
• Apply DOB feedback (carefully) to see if it is beneficial for improving motion control performance.
• Apply external force with f/t sensor in the hand to see about the impedance rendering