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Environmental conditions such as temperature and humidity can influence the adhesion forces, material and microtribological properties of microparts. To have a good understanding of microassembly, it is essential to study the influences of environmental conditions on the microassembly process and system. This paper presents our research in environmentally controlled microassembly. We have developed a microassembly system with controlled environment, which consists of an environmental control system and a microassembly platform. The environmental control system controls the environmental conditions including temperature and humidity in a closed chamber, providing a clean and vibration isolated environment for microassembly. The temperature can be controlled in the range of -10-40°C and relative humidity in the range of 5-80% RH. The microassembly platform, which is installed in the environmental control system, contains microrobotic instruments such as microgrippers, micromanipulator, positioning stages, microdispenser, ultraviolet light source, microscopes, etc. Experiments on the influences of environmental conditions on microassembly instruments and pick-and-place operations are systematically performed. The results are analyzed and presented.

This paper presents an optimization method to minimize the springback phenomenon, which generate the main dimensional errors in case of sheet metal forming. The present work deals with numerical simulation related to draw bending and springback of U-shaped part made from tailor welded blanks. The base materials from tailor welded blanks have different springback behaviours, fact that must be taken in consideration in the optimisation process. The Dynaform 5.8.1 software was used to simulate the forming process, in which the blank holder is segmented in two parts in order to apply different holding force for each material. In this research the blank holder forces and the deformation speed take different numerical values. The factorial simulations test plan was made using the Design Experts 7.0 software to cover completely the variation domain. The part obtained after each simulation is analyzed and measured to quantify the errors caused by springback. Parameters as: angle between flange and sidewall, angle...

This paper deals with some numerical simulation and experimental tests related to forming and springback of a U‐shaped part manufactured from tailor welded stripes. Final shape of the formed part manufactured by tailor welded stripes is seriously affected by springback effect. The materials tailored in the welded stripes have different springback values. This paper work is trying to prove out the important role of material rolling direction has on the springback reduction. The influence of the material rolling direction on the tailor welded stripes springback is examined using the simulation by finite element method (ABAQUS). Experimental tests have been done using different material rolling direction and maintaining constant all other parameters. The resulted parts were measured using a 3D scanning machine. An optimum material rolling direction is established and the results are presented in the final section of this paper.

This paper deals with some numerical simulation and experimental tests related to forming and springback of a U‐shaped part manufactured from tailor welded stripes. Final shape of the formed part manufactured by tailor welded stripes is seriously affected by springback effect. The materials tailored in the welded stripes have different springback values. This paper work is trying to prove out the important role of welding line placement has on the springback phenomenon. The influence of the welding line placement on the tailor welded stripes springback is examined using the simulation by finite element method (ABAQUS). Experimental tests have been carried out using different positions of the welding line and maintaining constant all other parameters. The resulted parts were measured using a 3D scanning machine. A comparison between simulation and experiment results is presented in the final section of this paper.

Environmental conditions, such as temperature and humidity can influence the adhesion forces and microtribological properties of microparts. To have a good understanding of microassembly, it is essential to study the influences of environmental conditions to microassembly process and system. This paper presents our research in environment controlled microassembly, including an environment controlled microassembly system and early results of the influences of environmental parameters on microassembly and pick-and-place operations. The environment controlled microassembly station can control the environmental conditions including temperature and humidity in a closed chamber where microassembly is carried out. The temperature can be controlled in the range of 10-40/spl deg/C and relative humidity of 5-80% RH. Experimental results of the influences of environmental conditions on a piezoelectric bender and piezo-ultrasonic stage are reported, as well as errors of pick-and-place operation. The experimental results show that both temperature and humidity can influence the performance and errors.

With the trend of miniaturization of mechatronics products, the demands on microassembly increase substantially. Due to the scaling effect, handling and planning in microassembly is considerably different from those in conventional assembly. One important issue is to study how the environmental parameters will shape the scaling effect and consequently the handling of micro parts. A controlled environment will enable a better understanding of the handling tasks in microassembly and consequently provide a necessary tool for the development of model-based microassembly methods. Moreover, environmental parameters can affect the performance of microassembly system. This paper will present our progress of developing a microassembly station with controlled environment. The microassembly station includes a microassembly platform that is able to mount various tools such as microscopes, mobile stages, micro grippers, etc. The microassembly platform is installed in a controlled environment where temperature and humidity can be controlled, and mechanical vibration is damped. Such a microassembly station facilitates researching microassembly methods and techniques under different environmental conditions. Early study of the effects of environmental parameters to microassembly system and pick-and-place operation is reported as well.