In this paper, we describe a generative process planning system for robotic sheet metal bending press-brakes. This process planning system employs a distributed planning architecture. Currently, our system consists of a central operation planner and three specialized domain speci c planners: tooling, grasping, and moving. The central operation planner proposes various alternative partial sequences and each specialized planner evaluates them based on its objective function. The central operation planner uses state-space search techniques to optimize the operation sequence. Once a CAD design is given for a new part, the system automatically determines: the operation sequence, the tools and robot grippers needed, the tool layout, the grasp positions, the gage and the robot motion plans for making the part. The distributed architecture allows us to develop an open-architecture environment for doing generative process planning and encapsulate the specialized knowledge in specialized planners.

A benchtop brain tissue-microelectrode insertion model system was developed to aid in improving the design of cortical neural interfaces. The model partially mimics the in vivo environment via the use of human cadaver brain specimens (nspecimen = 6), or agar gel exposed to physiologically relevant mechanical oscillations. 150 lpm diameter stainless-steel microelectrode wires (TS = 600 MPa) implanted 3.0 cm within fixed human primary auditory cortex (ntrial > 10) experienced 133 +/- 8 and 64 +/- 4 mN of peak and steady axial forces. When subjected to a 3 Hz, 3-mm vertical oscillation, dynamic force amplitudes (ntrial > 10) of 148 +/- 10 mN were measured. The model system allows the study and comparison of static and dynamic forces and their mechanical influences on proposed implanted microelectrode structures.

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Coordinated manipulation of micro-scale objects is critical for advancing several emerging applications such as microassembly and manipulation of biological cells. Most of the existing designs for micromanipulators are designed to accomplish primarily spatial positioning functionalities using positioning stages. Relatively, there are very few micromanipulators capable of ‘grip-and-place’ functionality that comprises both gripping and positioning at micro-scales. However, such manipulators are generally bulky. This paper introduces a novel concept of a miniaturized micromanipulator with multiple fingers for coordinated planar manipulation that involves both gripping and positioning of micro-scale objects. In this micromanipulator, multiple independently actuated fingers coordinate with each other to accomplish the manipulation. The paper presents a systematic design of the micromanipulator through shape optimization of each finger for a rationally chosen topology and a proof-of-concept prototype of the device fabricated using conventional microfabrication processes. Experimental results characterizing the input–output behavior of a finger mechanism in the prototype device are presented and an excellent correlation between the experimental results and the theoretical results validating both the design and the fabrication of the micromanipulator prototype is demonstrated. Experiments involving coordinated manipulation of 15 µm diameter polystyrene microspheres using multiple fingers in the micromanipulator station are also presented.

Micromanipulators for coordinated manipulation of micro- and nano-scale objects are critical for advancing several emerging applications such as microassembly and manipulation of biological cells. Most of existing designs for micromanipulators accomplish either primarily microgripping or primarily micropositioning tasks, and relatively, only a very few are capable of accomplishing both microgripping and micropositioning, however, they are generally bulky. This paper presents conceptualization, design, fabrication and experimental characterization a novel micromanipulation station for coordinated planar manipulation combining both gripping and positioning of micro- and nano-scale objects. Conceptually, the micromanipulation station is comprised of multiple, independently actuated, fingers capable of coordinating with each other to accomplish the manipulation and assembly of micron-scale objects within a small workspace. A baseline design is accomplished through a systematic design optimization of each finger maximizing the workspace area of the manipulation station using the optimization toolbox in MATLAB. The device is micromachined on a SOI (silicon-on-insulator) wafer using the DRIE (Deep Reactive Ion Etching) process. The device prototype is experimentally characterized for the output displacement characteristics of each finger for known input displacements applied through manual probing. An excellent correlation between the experimental results and the theoretical results obtained through a finite element analysis in ANSYS software, which validates both the design and the fabrication of the proof-of-the-concept, is demonstrated.