Annunziata, Salvatore: Bio-inspired control concepts for elastic rotatory joint drives. 2014
Inhalt
- Title
- Acknowledgement
- Abstract
- Table of Contents
- 1 Introduction
- 1.1 Classical stiff actuators versus compliant robotics joints
- 1.2 From biological systems to safe robots
- 1.3 Thesis organization
- 2 Mechanical impedance properties of muscle-joint systems
- 2.1 Musculoskeletal joint setup
- 2.1.1 Hill-type muscle model
- 2.1.2 Antagonistic joint geometries with two muscles
- 2.1.3 Simplified model of the human elbow joint with a pulley
- 2.2 Mechanical impedance in a pulley hinge joint geometry
- 2.2.1 Reciprocal activation and co-activation of muscles
- 2.2.2 Joint stiffness computation
- 2.2.3 Joint viscosity computation
- 2.3 Stiffness nodes in the joint range of motion
- 2.3.1 Regions in the joint range of motion resulting from overlap of the force-length curves
- 2.3.2 Stiffness nodes evaluation for a pulley hinge joint geometry
- 2.3.3 Active force-length function approximation: cubic spline interpolation
- 2.3.4 Stiffness nodes prediction for different force-length curve approximations
- 2.3.5 Integration of a compliant tendon in the muscle model
- 2.4 Summary
- 3 Control approaches to increase the stiffness variability in multi-muscle driven joints
- 3.1 Introduction
- 3.2 Concurrent torque/stiffness control in the presence of stiffness nodes
- 3.2.1 Stiffness generated by two muscle pairs in a pulley joint
- 3.2.2 Control approach adopting reciprocal activation and co-activation (dedicated muscles)
- 3.2.3 Stiffness node control strategy
- 3.2.4 Simulation results for a fixed joint position
- 3.3 Optimal stiffness variation across a wide joint range of motion
- 3.4 Torque/stiffness control approaches adopting the optimal muscle setup
- 3.4.1 Activation overflow strategy
- 3.4.2 Open-loop strategy with inverse model and activation overflow
- 3.4.3 Closed-loop control with inverse model and activation overflow
- 3.4.4 Response time comparison
- 3.5 Summary
- 4 Bio-inspired control laws adopting antagonistic muscle actuation in a simplified elbow joint setup
- 4.1 Stability analysis of an antagonistically actuated hinge joint setup with a pulley
- 4.2 Bio-inspired control strategy for stable compliant joints
- 4.2.1 Basic concurrent position/stiffness control
- 4.2.2 Biological feedback system for the control of a single muscle
- 4.2.3 Bio-inspired position controller
- 4.2.4 Bio-inspired stiffness controller
- 4.3 Bio-inspired position/stiffness control and simulation results
- 4.4 Summary
- 5 Application of the bio-inspired control laws on a compliant rotatory joint drive
- 5.1 Compliant robotics joint drive: design and identification
- 5.1.1 Mechatronic setup
- 5.1.2 Elastomer coupling model
- 5.1.3 Mechanical model of the compliant joint drive
- 5.2 Identification of the joint drive model parameters
- 5.2.1 Moments of inertia and gearbox torsional stiffness
- 5.2.2 Motor side friction
- 5.2.3 Parameters optimization through gray-box identification
- 5.3 Control of the loaded joint with fast system dynamics
- 5.3.1 Motor speed control and friction compensation
- 5.3.2 Output torque control design
- 5.3.3 Output position control
- 5.3.4 Mechanical impedance analysis
- 5.4 Experimental results
- 5.5 Summary
- 6 Discussion
- 6.1 Bio-inspired control achievements
- 6.2 Musculoskeletal model and its limitations
- 6.3 Implications of stiffness node analysis
- 6.4 Implications of a multi-muscle setup
- 6.5 Implications of the stability analysis for the muscle-driven hinge joint
- 6.6 Advantages for other research and future work
- Bibliography