Precision connector assembly automation

Telecommunication systems, network servers, mainframes, and high-performance computers contain several printed circuit boards (PCBs) that are mounted in card-cage assemblies. Level-3 connectors, often called board-to-board connectors, transmit signals between the primary backplane PCB and the daughter card PCBs. These connectors are customized for each PCB by configuring modules along the length of the connector. Hence, the connector's assembly system must flexibly accommodate the connector configurations. Prior to this research, the assembly of daughter card connectors was a manual process. This thesis presents the conceptual design of an assembly cell, and thoroughly presents the selected concept, a flexible assembly system. In the flexible assembly system, the connector is fixtured on a pallet and transferred to assembly stations on a conveyor. The pallet must be precisely located at each station, to minimize the relative errors between the new component and the connector on the pallet. Kinematic couplings deterministically locate one rigid body with respect to another. Therefore, a pallet system was developed that uses split-groove kinematic couplings between the pallets and machines. Experiments demonstrated that the split-groove kinematic pallet was approximately O1X more repeatable than conventional pallet location methods. The design is evident in the fabrication and operation of the first automated machines for the connector assembly system. In automated machinery, kinematically coupled bodies are often subjected to ranges of disturbance forces. This thesis presents new methods for analyzing the static equilibrium, errors due to contact deformation, and contact stresses that result from disturbance forces. In addition, the manufacturing errors within individual pallets and machines combine to cause system-wide, variability in pallet location. Two methods are presented for estimating the system-wide variability in the position and orientation of the pallets.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

1999

Author dc:creator

• Vallance, Robert Ryan

Advisor dc:contributor.advisor

• Alexander H. Slocum.

• Mechanical Engineering

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/38433

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/38433