Design, Dynamics Analysis, and Real-Time Stiffness Control of a Variable Stiffness Joint
Abstract
:1. Introduction
2. Mechanical Design and Mathematical Analysis of SCM-VSJ
2.1. Mechanical Design
2.2. Mathematical Derivation
2.3. Characteristic Analysis
3. Dynamics Analysis of SCM-VSJ
3.1. Dynamical Model
3.2. Dynamics Characteristics of SCM-VSJ
4. Real-Time Dynamics Stiffness Control of SCM-VSJ
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Parameters | Value | Unit |
---|---|---|
Rated power of servo motor | 200 | |
Rated torque of servo motor | 0.64 | |
Reduction ratio of harmonic reducer | 50 | - |
Rated torque of harmonic reducer | 25 | |
Rated torque of DC geared motor | 0.2 | |
Reduction ratio of DC geared motor | 19 | - |
Speed before deceleration of DC geared motor | 395 |
Parameters | Value | Unit |
---|---|---|
SCM-VSJ maximum diameter D | 130 | mm |
Central cube side length | 8 | mm |
SCM-VSJ passive deflection angle | [−8,8] | ° |
Spring bar diameter | 3 | mm |
Spring bar length | 110 | mm |
The length from one side of the spring bar to the central cube | 51 | mm |
Spring bar elastic modulus | 206 | |
Horizontal distance between the joint center point O and the gear shaft | 5 | mm |
Length of the crank | 14 | mm |
Length of connecting rod | 34 | mm |
The eccentricity of the crank slider mechanism | 12 | mm |
Category | SCM-VSJ | VSJ | VsaUT-II |
---|---|---|---|
Size/mm | ∅130 × 260 | ∅146 × 144 | - |
Weight/kg | 4.5 | 4.95 | 2.5 |
Stiffness/() | [368, 3968] | [252, 3674] | [0.7, 948] |
Deformation angle/° | [−8, 8] | [−180, 180] | [−28.6, 28.6] |
Rated power/ | 0.2 | 0.2 | - |
Parameters | Meaning | Unit |
---|---|---|
The input torque of the main motor | ||
The electrical damping coefficient of the main motor | ||
The input angle of the main motor | ||
The moment of inertia of the main motor | ||
The output torque of the main motor | ||
The reduction ratio of the harmonic reducer | - | |
The transmission efficiency of the harmonic reducer | - | |
The output angle of the harmonic reducer | ||
The output torque of the harmonic reducer | ||
The joint stiffness | ||
The damping coefficient of the variable stiffness module | ||
The output torque of the flexible part | ||
The equivalent moment of inertia of the output | ||
The joint output angle | ||
The damping coefficient of the output | ||
The load torque | ||
The input moment of the stiffness adjustment motor | ||
The moment inertia of the stiffness adjustment motor | ||
The damping coefficient of the stiffness adjustment motor | ||
The angle of the stiffness adjustment motor | ||
Transfer efficiency of stiffness adjusting motor | - | |
Resistance moment caused by spring bar | ||
Output torque of stiffness adjustment motor | ||
Reduction ratio of the stiffness adjusting motor | - | |
The joint passive deflection angle |
Parameters | Value | Parameters | Value | Parameters | Value |
---|---|---|---|---|---|
0.071 | 0.08 | ||||
0.1 | 0.095 | ||||
0.8 | 50 | ||||
19 | 0.8 |
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Yu, Y.; Wei, S.; Ji, Q.; Yang, Z. Design, Dynamics Analysis, and Real-Time Stiffness Control of a Variable Stiffness Joint. Electronics 2020, 9, 973. https://doi.org/10.3390/electronics9060973
Yu Y, Wei S, Ji Q, Yang Z. Design, Dynamics Analysis, and Real-Time Stiffness Control of a Variable Stiffness Joint. Electronics. 2020; 9(6):973. https://doi.org/10.3390/electronics9060973
Chicago/Turabian StyleYu, Yang, Shimin Wei, Qiunan Ji, and Zheng Yang. 2020. "Design, Dynamics Analysis, and Real-Time Stiffness Control of a Variable Stiffness Joint" Electronics 9, no. 6: 973. https://doi.org/10.3390/electronics9060973
APA StyleYu, Y., Wei, S., Ji, Q., & Yang, Z. (2020). Design, Dynamics Analysis, and Real-Time Stiffness Control of a Variable Stiffness Joint. Electronics, 9(6), 973. https://doi.org/10.3390/electronics9060973