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Distributed manipulators - consisting of a set of actuators or robots working cooperatively to achieve a manipulation task - are robust and flexible tools for performing a range of planar manipulation skills. One novel example is the delta array, a distributed manipulator composed of a grid of delta robots, capable of performing dexterous manipulation tasks using strategies incorporating both dynamic and static contact. Hand-designing effective distributed control policies for such a manipulator can be complex and time consuming, given the high-dimensional action space and unfamiliar system dynamics. In this paper, we examine the principles guiding development and control of such a delta array for a planar translation task. We explore policy learning as a robust cooperative control approach, allowing for smooth manipulation of a range of objects, showing improved accuracy and efficiency over baseline human-designed policies.
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Extensible High Force Manipulator For Complex Exploration
The development of compliant robotic manipulators which can show length change, compliance and dexterity could assist many challenging applications. Potential applications range from dexterous manipulation, robotic surgery or exploration of challenging environments. Despite significant developments in both fabrication and control approaches for continuum body manipulators, there have been few demonstrations of continuum body systems which display all these properties. We present a method for fabricating a continuum manipulation which shows extension, high force movements and a range of dexterous position. This approach uses 3D printing to create a flexible rack and pinion system. These high torque mechanisms are mounted at points along the 3D printed tracks to allow complex shape control of the continuum system. A controller has been also been developed based on a Piecewise Constant Curvature approximation to allow the position of the tip of the manipulator to be controlled, and motion paths to be followed. In this work, we show the force capabilities of this manipulator and demonstrate how multiple segments can be created for more complex movements.
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- Award ID(s):
- 1830901
- PAR ID:
- 10188462
- Date Published:
- Journal Name:
- IEEE Conference on Soft Robotics (RoboSoft)
- Page Range / eLocation ID:
- 733 to 739
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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null (Ed.)Distributed manipulators - consisting of a set of actuators or robots working cooperatively to achieve a manipulation task - are robust and flexible tools for performing a range of planar manipulation skills. One novel example is the delta array, a distributed manipulator composed of a grid of delta robots, capable of performing dexterous manipulation tasks using strategies incorporating both dynamic and static contact. Hand-designing effective distributed control policies for such a manipulator can be complex and time consuming, given the high-dimensional action space and unfamiliar system dynamics. In this paper, we examine the principles guiding development and control of such a delta array for a planar translation task. We explore policy learning as a robust cooperative control approach, allowing for smooth manipulation of a range of objects, showing improved accuracy and efficiency over baseline human-designed policies.more » « less
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We report on the design and the modeling of a three-dimensional (3D) printed flexure-based actuation mechanism for robotic microtweezers, the main body of which is a single piece of nylon. Our design aims to fill a void in sample manipulation between two classes of widely used instruments: nano-scale and macro-scale robotic manipulators. The key component is a uniquely designed cam flexure system, which linearly translates the bending of a piezoelectric bimorph actuator into angular displacement. The 3D printing made it possible to realize the fabrication of the cam with a specifically calculated curve, which would otherwise be costly using conventional milling techniques. We first characterized 3D printed nylon by studying sets of simple cantilevers, which provided fundamental characteristics that could be used for further designs. The finite element method analysis based on the obtained material data matched well with the experimental data. The tweezers showed angular displacement from 0° to 10° linearly to the deflection of the piezo actuator (0–1.74 mm) with the linearity error of 0.1°. Resonant frequency of the system with/without working tweezer tips was discovered as 101 Hz and 127 Hz, respectively. Our design provides simple and low-cost construction of a versatile manipulator system for samples in the micro/meso-scale (0.1–1 mm).more » « less
- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/RoboSoft48309.2020.9116024
