Novel Pneumatic Soft Gripper Integrated with Mechanical Metamaterials for Enhanced Shape Matching Performance
Abstract
1. Introduction
2. Gripper Enhanced by Mechanical Metamaterial
2.1. Pneumatic Soft Actuator
2.2. Attached Mechanical Metamaterial for Higher Shape Match Performance
3. Finite Element Analysis (FEA) of Traditional and Novel Assembled Gripper
3.1. FEA on Traditional Gripper
3.2. FEA on Novel Assembled Gripper
4. Data-Driven Inverse Design of Novel Assembled Gripper
4.1. Parametric Finite Element Analysis Model
4.2. Generation of Dataset for Deep Learning
4.3. Forward Design Neutral Network
4.4. Inverse Design Neutral Network
4.5. Design Results
5. Experiments and Validation
5.1. Preparation of the Novel Assembled Gripper
5.2. Performance Testing and Results Discussion
5.3. Deformation of Soft Grippers with Integrated Mechanical Metamaterials
5.4. Experimental Validation of Shape-Matching Control in Soft Grippers
5.5. Discussion and the Limitations
- (1)
- Structural Design: Metamaterials are silicone-bonded “patches” on the fingertip (not integral). Long-term cyclic bending may cause adhesive failure (shear fatigue, peeling, creep); adhesive thickness/coating errors affect stiffness/Poisson’s ratio, with no quantified error sensitivity or tolerance control yet.
- (2)
- Overly Simple Optimization Objective: The deep learning loss function only uses sampling point z-coordinate deviation (focusing on geometric fit), ignoring gripping force, peak contact stress, fatigue life, and airtight safety margin. This risks crushing fragile objects (despite good profile matching) or early cracking.
- (3)
- Inadequate Experimental Coverage: Experiments only used two samples (planar, wedge-shaped; monotonic curvature, no depressions), failing to verify “high adaptability to complex/fragile targets.” Tests used only single-pressure loading (no cyclic tests) and lacked pressure retention/profile drift records, providing no basis for industrial service life.
6. Conclusions
- (1)
- This study presents the structural design of an integrated gripper, validated through FEA to ensure feasible deformation under pneumatic loads. The incorporation of Gibson hexagonal unit-based metamaterials enables tailored surface deformation, significantly improving contact conformity with complex object geometries.
- (2)
- This study develops a robust deep learning framework, comprising forward and inverse neural networks, which efficiently predicts gripping surface deformation and enables inverse design of metamaterial parameters for desired shapes, significantly reducing design complexity. This data-driven approach allows rapid generation of high-quality design solutions, overcoming the limitations of traditional trial-and-error methods.
- (3)
- This study demonstrates successful fabrication via 3D printing and silicone casting, with experimental results confirming that the optimized gripper achieves remarkable shape-matching performance and stable gripping of test objects. Machine vision-based validation demonstrated average shape deviation reductions of over 80% compared to initial designs, highlighting the practical effectiveness of the proposed method.
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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L | W | H | R | ti | to | d | r | w |
---|---|---|---|---|---|---|---|---|
110 mm | 26 mm | 19 mm | 16 mm | 2 mm | 3 mm | 3 mm | 13 mm | 2 mm |
Exposure Time | Light-Off Time | Bottom Exposure Time | Number of Bottom Layers | Z-Axis Lift Height | Z-Axis Lift Speed | Z-Axis Retract Speed |
---|---|---|---|---|---|---|
2.2 s | 2 s | 40 s | 5 | 5 mm | 4 mm/s | 4 mm/s |
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Han, Z.; Zhang, B.; Sun, W.; Xu, Z.; Chen, X.; Weng, S.; Zhang, X. Novel Pneumatic Soft Gripper Integrated with Mechanical Metamaterials for Enhanced Shape Matching Performance. J. Manuf. Mater. Process. 2025, 9, 330. https://doi.org/10.3390/jmmp9100330
Han Z, Zhang B, Sun W, Xu Z, Chen X, Weng S, Zhang X. Novel Pneumatic Soft Gripper Integrated with Mechanical Metamaterials for Enhanced Shape Matching Performance. Journal of Manufacturing and Materials Processing. 2025; 9(10):330. https://doi.org/10.3390/jmmp9100330
Chicago/Turabian StyleHan, Zhengtong, Boqing Zhang, Wentao Sun, Ze Xu, Xiang Chen, Shayuan Weng, and Xinjie Zhang. 2025. "Novel Pneumatic Soft Gripper Integrated with Mechanical Metamaterials for Enhanced Shape Matching Performance" Journal of Manufacturing and Materials Processing 9, no. 10: 330. https://doi.org/10.3390/jmmp9100330
APA StyleHan, Z., Zhang, B., Sun, W., Xu, Z., Chen, X., Weng, S., & Zhang, X. (2025). Novel Pneumatic Soft Gripper Integrated with Mechanical Metamaterials for Enhanced Shape Matching Performance. Journal of Manufacturing and Materials Processing, 9(10), 330. https://doi.org/10.3390/jmmp9100330