1. Changing Objectives of Optimization 유리 Movement Research Lab

2. Overview Objectives Muscle actuation 150 cal/m

3. Overview(cont.) Joint torque 180 cal/m Metabolic energy expenditure 220 cal/m

4. Topics 1. Metabolic energy expenditure minimization 2. Stability experiment 3. Co-activation rate

5. Topics 1. Metabolic energy expenditure minimization 2. Stability experiment 3. Co-activation rate

6. Metabolic energy expenditure

9. Topics 1. Metabolic energy expenditure minimization 2. Stability experiment 3. Co-activation rate

10. Trade-off Optimality Stability

11. Stability experiment Unknown factors -Varying external forces -User inputs -When transitions occur between controllers -Motor noises WANG, J. M., FLEET, D. J., AND HERTZMANN, A. 2010. Optimizing walking controllers for uncertain inputs and environments. ACM Transactions on Graphics 29, 4.

12. Stability experiment(cont.) Unknown factors -Varying external forces -User inputs -When transitions occur between controllers -Motor noises

13. Varying external forces N/ 0.2s Muscle ActuationJoint torqueMEE 100XXΔ 80ΔOO 60OOO 40OOO 20OOO

14. Topics 1. Metabolic energy expenditure minimization 2. Stability experiment 3. Co-activation rate

15. Co-activation rate(CR)

16. Coactivation for anterior tibialis / lateral gastrocnemius Muscle actuationJoint torqueMetabolic energy Anterior Tibialis Lateral Gastrocnemius