Yoshiaki Komura

Layout optimization of manufacturing cells and allocation optimization of transport robots in reconfigurable manufacturing systems using particle swarm optimization

This paper proposes a 3D graphics simulation environment for the analysis and evaluation of reconfigurable manufacturing systems. The reconfigurable manufacturing systems consist of transport robots; input stations, output stations, movable manufacturing cells, and objects to process. The layout of the manufacturing cells and the allocation of transport robots are optimized using particle swarm optimization. The effectiveness of the simulator is validated through simulation results of several manufacturing cases.

Development of a Precision Assembly System Using Selective Assembly and Micro Machining

In this paper we propose a new combinatorial optimization method for parts matching in a precision assembly system. This method combines selective assembly with micro machining so as to produce high precision assembled units. From the simulation results, it is presented that the system is effective in a small lot production, where higher assembly rates can not be attained with conventional methods, in such that a higher rate is obtained if micro machining is used alongside.

Reaction force inspection system using wavelet transforms and neural networks

Looks at a system for inspection of the quality of a probes reaction force characteristics. This system, until now considered difficult to realize, automates the inspection method utilizing the touching of an inspectors finger. Wavelet transformation and a neural network (NN) approach are applied to the system for probes to learn an inspectors finger judgment. We provide an input layer of a NN with thirty-three nodes corresponding to a time series of reaction forces of a probe and an output layer with one node corresponding to a judgment; being one of non-defective, defective, or unable to judge. From experimental results, the effectiveness of the system has been clarified.

Reaction Force Inspection System Using Neural Network Classifier

People recognize the quality of a product while in operation by hands or fingers. The operation feeling by hands or fingers is one of the important indexes for the high-grade products. However, skilled inspectors are used to inspect some products because automatic inspection is technologically difficult or too high in cost. This paper looks at a system for inspection of the quality of a product’s reaction force characteristics. This system, until now considered difficult to realize, automates the inspection method utilizing the touching of an inspectors finger. Neural network classifier is applied to the system for products to learn an inspectors finger judgment. We provide an input layer of a neural network classifier with nodes corresponding to time-and frequency-domain features of reaction forces of a product and an output layer with three nodes corresponding to a judgment; being one of non-defective, defective, or unable to judge. From experimental results, the effectiveness of the proposed neural network classifier has been clarified.

Reconfigurable parts feeding system using arrayed vibratory units made by stereolithography

A new reconfigurable parts feeding system using arrayed vibratory units made by stereolithography has been developed and investigated. The parts feeding motion is achieved by vibration of an inclined pin grid array using piezoelectric actuators. Experiments on moving objects have been successfully performed. The vibratory unit has a large number of inclined pins, each a height of 3 mm and diameter of 0.5 mm. The motions of the parts feeding system has been demonstrated experimentally, and lifetime measurements demonstrated the long-term stability of the system. The functionality of the photopolymer resin pins is unaffected through 110 days continuous use.

Combinatorial Optimization of Parts Matching for Parts Recycling. Parts-Mix of Reusable Parts and New Parts.

In a parts recycling system, reusable parts in the collected waste products are employed to produce new products with new parts. Two assembly methods are considered in the parts recycling system. The primary method is random assembly, in which new parts are selected randomly from the entire population and assembled. The remaining method is selective assembly based on the combinatorial optimization method, in which a combination of reusable parts and new parts is optimized so that high quality assembled units are obtained in a lot unit at the maximum assembly rate while dimensions of each part are referred to appropriately. The assembly methods are applied to the parts recycling system where hole parts are combined with shaft parts. In this paper the effectiveness of parts mix, reusable parts and new parts, is clarified in various situations.