Assembly of a Gripper for a Wall-Mounting Robot


Precizika Metal is a typical SME company that is evolving from being a component supplier to delivering full solutions. This implies an increasing need to deliver fully assembled products to clients. 

Description of the experiment

The Precizika Metal use case consists of the assembly of a part of a glass mounting gripper. Assembly parts enter the cell on a pallet situated on a trolley equipped with a plug and produce (PnP) connector. In this experiment, a total of three PnP trolleys are used.

While a lot of Precizika Metal use case aspects called for a non classic approach to automation, hence some innovative approaches had to be specially developed for this experiment. Both aspects presented here are related to screwing. The first aspect tackles the improvement of the screw mechanism and the second one solves the problem of limited workspace by introducing a passive rotation table.

Although the screw mechanism developed for other ReconCell experiments, further improvements were needed. As can be seen in the final implementation video, the whole screw mechanism extension was upgraded. Exchanging 3-D printed parts with brass parts improved stability of the screw bit and improved the precision of the top. A new design for the screw bit exchange improved the overall reliability of the robot assisted bit exchange. For more information on the screwdriver please see: http://www.reconcell.eu/content/space/reconfiguration.html

As the kendrion screw positions are spaced at 120° (part no. 8), they cannot be reached from the limited workspace of the robot. This is additionally limited by the overall length of the screwdriver. An expensive off-the-shelf solution would be an active rotation table. However, as one of the main paradigms of the ReconCell project are affordable solutions for SMEs, a passive rotation table was designed. The table is locked in place with three pneumatic actuated pins. When they are released the table can be rotated freely by the robot. This enabled us to reach all sides of the assembly area while keeping the costs of the hardware relatively low. 

Solution

The final solution is the ReconCell workcell that includes the new modules for this use case. The workcell has been reconfigured by manually interchanging modules, like the tool rack trolley, part trolley and press trolley in order to accommodate the assembly of this product.

Outcome

The Precizika Metal case showed that the use cases are not very good candidates as potential ReconCell customer. A first  evaluation of Precizika Metal showed that in the specific use case for ReconCell, the project was complex where too many parts are being used, and many assembly processes are involved. Considering the production volume, the ReconCell product has been evaluated not to be a positive business case for Precizika Metal.



Project:

Enterprises:
Precizika Metal ‘

Sector
Other manufacturing

Keywords