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Soft robots have the potential to interact with sensitive environments and perform complex tasks effectively. However, motion plans and trajectories for soft manipulators are challenging to calculate due to their deformable nature and nonlinear dynamics. This article introduces a fast realtime trajectory generation approach for soft robot manipulators, which creates dynamically-feasible motions for arbitrary kinematically-feasible paths of the robot’s end effector. Our insight is that piecewise constant curvature (PCC) dynamics models of soft robots can be differentially flat, therefore control inputs can be calculated algebraically rather than through a nonlinear differential equation. We prove this flatness under certain conditions, with the curvatures of the robot as the flat outputs. Our two-step trajectory generation approach uses an inverse kinematics procedure to calculate a motion plan of robot curvatures per end-effector position, then, our flatness diffeomorphism generates corresponding control inputs that respect velocity. We validate our approach through simulations of our representative soft robot manipulator along three different trajectories, demonstrating a margin of 23x faster than realtime at a frequency of 100 Hz. This approach could allow fast verifiable replanning of soft robots’ motions in safety-critical physical environments, crucial for deployment in the real world.
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Design and Fabrication of Sensorized Soft Effectors for Modular Soft Effectors
Biomimicr y is a i eld of study that involves imitating the designs and processes of nature to solve problems using man- made systems. Biomimicr y offer s an empathetic, interconnected under standing of how life wor ks and where we i t in. In bio- inspired designs, the main challenge is to develop a sustainable and effective fr amewor k that can be used in the real wor ld. M ost of the soft robotic designs are state-of-the-ar t models that cannot be used in real sensing applications. In this research, we propose a sustainable sensor-integr ated modular soft robot model that can be used for locomotion and gr ipping applications. This wor k presents the steps involved in modeling, designing, and fabr icating soft and l exible end effector s that can be used for soft robots with integr ated soft stretchable sensor s. We demonstr ate the design methodology involved in modeling and simulating the proposed model for robots that would require effector s with increased functionalities.
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- Award ID(s):
- 1924117
- PAR ID:
- 10451159
- Date Published:
- Journal Name:
- IEEE International Conference on Automation, Control and Robots
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
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