Handling Processes in Microsystems Technology

Principle of a Submerged Freeze Gripper for Microassembly

“…They need only one accessible surface but are limited to flat-side components or components with simple 3D shapes. Their cycle time is generally very short (< 0.1 s) [9], [14]. Features of capillary grippers [15]- [17] are similar to cryogenic grippers, but their miniaturization is limited because of adhesion perturbations during the release phase.…”

“…Nevertheless, the adhesion perturbations increase when part size diminishes and force control is required for fragile components. In addition, it is necessary to have at least two accessible surfaces to grasp parts [9], [13], [14]. Vacuum grippers have weak mechanical constraints.…”

First research achievements of the project ASSEMIC on microhandling and - assembly technologies

“…Among the tweezers-type grippers, there are many different possible designs, depending on the actuation principle used for the clamping mechanism, which can be piezoelectric, SMA (Shape Memory Alloy), an electrostatic comb, thermal actuator, etc. [5] [6] Within the task devoted to the development of Advanced Microhandling tools, research has been done on different types of microgrippers, as well as special fabrication methods for such micro-grippers. Nascatec has reported an electrostatic microgripper and performed additional mechanical simulations by means of Finite Element Analysis (FEM), in order to understand the key contributions to gripper distortion, evaluate the main variables of influence and determine optimum geometrical dimensions and fabrication parameters.…”

“…Besides the different types of microgrippers and actuation principles, parasite forces and adhesion problems are also dealt with [5]. Sticking effects a particularly important issue in the microscale, due to the effects of the scaling of laws, which makes van der Waals, capillary and electrostatic forces to preponderate over gravitational forces.…”

“…There are many other aspects involved in strategies for handling of microcomponents and explored in Seibersdorf and Politechnika Warszawska-WUT 's report. For example, different strategies can be adopted for the positioning of the handled objects, such as compliance grippers, which compensate for positional errors as well as prevent breakage of the gripper, manipulation primitives and methods to produce vibratory agitation, fixing the object when it randomly reaches the desired final position [5].…”