Sven Rathmann

Active Gripper for Hot Melt Joining of Micro Components

Precision assembly of hybrid micro systems requires not only a high precision handling and adjusting of the parts but also a highly accurate and fast bonding technique. In this field adhesive technology is one of the major joining techniques. At the Collaboration Research Center 516, a batch process based on a joining technique using hot melt adhesives was developed. This technique allows the coating of micro components with hot melt in a batch. The coating process is followed by the joining process. Due to this, the time between coating and joining can be designed variably. Because of the short set times of hot melt adhesives short joining times are possible. For this assembly process adapted heat management and adapted gripper systems are very important. Primarily, the conception and construction of suitable grippers, which realize the complex requirements of the heat management, meet a high challenge. This paper presents an active gripper system for the joining of micro parts using hot melt adhesives. Furthermore, first examinations and results of an assembly process using this gripper for bonding with hot melt adhesives are presented.

Concepts for Hybrid Micro Assembly Using Hot Melt Joining

Nowadays, the production of 3D MEMS and MOEMS is carried out by using hybrid integration of single components, for which batch production is normally preferred. In this field, adhesive technology is one of the major joining techniques. At the Collaboration Research Center 516, a batch process based on a joining technique which uses hot melt adhesives was developed. This technique allows the coating of micro components with hot melt in a batch. The coating process is followed by the joining process. Due to this, the time between coating and joining can be designed variably. Because of the short set times of hot melt adhesives, short joining times are possible. For this assembly process adapted heat management is necessary. This paper presents adapted heating management concepts and gripping systems which allow a fast and accurate assembly of hybrid micro systems with hot melt coated components. Therefore, the chosen gripping system depends on the process and heat management concept as well as the thermal properties of the components. Furthermore, the simulative and experimental results of the heat management concepts will be discussed.

Flexible forming with hexapods

The work presented in this paper provides the basis for an extension of conventional orbital forming to a new, flexible forming process. A hydraulically actuated hexapod is used to move a swage in order to extrude a work piece towards a desired shape. This paper presents an analytical model of the actuators and the dynamics of the hexapod. This model is used for developing a cascaded position control law, and for developing a simulation environment representing the machine and the work piece in an entire forming process loop. The design of the machine is briefly introduced and results of position control are presented.

Sensor Guided Micro Assembly by Using Laser-Scanning Technology

To recognize geometric objects of components in assembly processes, in particular of microelectronic or micro system components, nowadays the use of vision systems is preferred. These systems are working very fast but the results depend on ambient conditions, especially of light settings. They deliver 2D object information referring to the image plane of a camera. In most sensor guided assembly systems, additional to vision systems laser displacement sensors are implemented to get information about the third dimension, the components height. In this paper a scanning method is presented which enables object recognition by using a laser positioning sensor and to use the achieved measuring values for a sensor guided assembly process.

Design of a Microassembly Process Based on Hot Melt Adhesives

Within a microassembly process, four independent variables can be identified, which influence the overall accuracy of the assembled part in a high dimension. These variables are the uncertainty of the moving parts of the handling system, the component fixtures, the gripping elements and the joining technology. Due to the complexity of these variables, an all-embracing conclusion of the resulting joining uncertainty, primarily taking into consideration the different effects of liquid adhesives, cannot be made. In this context, the curing process, the surface properties, and the design of the assembly process are discussed in detail, with special emphasis on a new approach that takes advantage of the favorable characteristics of physical setting hot melt adhesives instead of chemically reactive liquid adhesives. The integration of the newly developed assembly processes using hot melt adhesives results in increasingly accurately assembled microcomponents.

Design of an Automated Assembly for Micro and Nano Actuators

In addition to the development of new technologies for the manufacturing of electromagnetic micromotors, the development and production of a micromotor was in the main focus of this Collaborative Research Center. This chapter presents an approach for the assembly of the variable reluctance microstep motors and the automation of the assembly. The results have been achieved by the interdisciplinary cooperation of different subprojects in the domains of design, manufacturing, and assembly technologies. After a short introduction on the importance of an automated assembly of the high-tech product microactuator and its components, the assembly concepts for the linear microactuator and the xy-microactuator are explained.