Investigation of Robotic Platforms for Handling of Microsystems

 

Work of M.Burman for M.Sc. degree in Mechanical Engineering. IIT, Israel.
Supervisor: Prof. M.Shoham. Mechanical Engineering. IIT, Israel, Dr. Shmuel Kaldor, Raphael,Israel.

 

Abstract:
    Today, techniques derived from microelectronics procedures enable to manufacture basic elements for MEMS like actuators, joints gears etc. but there is a lack of tools to manipulate these elements especially during development stage.

    The typical handling tasks/operations for the prototyping Micro Electro Mechanical Systems which the desired microsystems have to perform are: non tactile inspection, tactile elastic testing, cleaning, bonding, gluing, mechanical measurements, electronic
measurements, optical measurements. Many of the above listed operations are considered today as problematic technology tasks.

    Since, the typical dimensions of MEMS range from tens of microns to a few millimeters there is the strong demand for high accuracy and small dimensions of tools and microsystems to manipulate these elements. Therefore, miniature manipulating systems have to be developed.

    Classical robots are not accurate enough to manipulate these components, also they are suffer from a scaling affect since driving forces decreases with dimensions at much faster rate than disturbances (like friction). Therefore, at some scale, friction forces become larger than inertia forces and the system is no more operative.

    The classical serial mechanical architecture may, however, be substituted by closed-loop architecture called parallel architecture. The system based on that architecture does not suffer from scaling affect and has advantages like high rigidity and accuracy and high load pay ratio. The limited work volume of these structures is not a disadvantage, since all tasks performs in a very small volume.

    The purpose of that work is to develop a robotic microsystem base on the parallel architecture that will be able to manipulate MEMS elements during development stage.

 

Examples of some required tasks:

   tactile elastic testing of MEMS

electronic measurements and testing

cleaning of CMOC

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At the first step of the development of microsystem we require to perform a bonding task, because it is a complicate and includes other required subtasks.

 

The bonding task have to be performed under the ‘AXIOPLAN 2’ microscope at the laboratory conditions.

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The Robotic System:

The prototype of the manipulating system is a robot with parallel architecture of Stewart type.

First prototype simulation

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Robot on the microscope table

The prototype of the robot

 


Second prototype simulation

Click on, to see large window simulation movie
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Characterization of bonding task:

I

II

III

1 - substrate   2 - frame    3 - bonder  4 - stop bump

The bonding task consist of:

1. Holding substrate – ‘1’

2. Holding frame – ‘2’ ( have to be glued ). (I)

3. Bringing ‘2’ against ‘1’ with desired orientation and accuracy.

4. Bringing ‘2’ and ‘1’ in touch between bonding points (II).

5. Pressing ‘2’ against ‘1’ for firstly bonding with force and orientation control.

6. Time delay for bonding improvement with pressing force and orientation control of ‘2’ (III).

 

Force, required for that task, depends on number of bonding points.
At present stage of the research the required force is 100 grams.
Also the system may be subjected to about 100 - 150°C temperature.

Expected end of the research – autumn 2000.

Created and maintained by Michael Burman