Integration of Additive Manufacturing with CNC Sheet Metal Fabrication for Hybrid Fixtures: Design and Implementation of Powder Bed Fusion Tooling Surfaces

The objective of this project was to facilitate the integration of additive manufacturing and CNC sheet metal fabrication to create hybrid check fixtures. In this case, the tool comprises a sheet metal base and a powder bed fusion cover. Using the Agile product development framework, the team conducted a series of sprints going from concept models to a final production tool in just over two months. Additive manufacturing investigations conducted to converge on the optimal production solution include studies on dimensional process capability, additive process type, material tradeoffs, and business factors. Moreover, several sheet metal and tubing structures were tested to achieve a highly accurate base for the additively manufactured surface. The integration of these parts was enabled by elastic-averaging-based connector geometries that also evolved throughout the different sprints in conjunction with results from efficient simulation models. The production hybrid fixture presented a range of benefits for automotive OEM and project sponsor, General Motors (GM). Compared to traditional fixtures, the lead time was shortened by 92%, the cost was reduced by 65%, and the recyclability increased from 59% to 100%. These benefits were achieved while meeting all product owner requirements and technical specifications. Given the increasing demand for check fixtures owing to shortening product lifecycles, it is expected that the savings generated can scale up significantly. Moreover, many of the techniques developed can be applied to other types of fixtures such as those used for welding and subassembly. The project was also successful at fulfilling an internal company goal of generating sufficient traction to launch a series of collaborative initiatives between the sheet metal fabrication and additive manufacturing teams at GM.

Name thesis:degree_name

Master

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2022

Author dc:creator

• Cunningham, Andrew T.

Advisor dc:contributor.advisor

• Hardt, David

Statement dc:rights

• In Copyright - Educational Use Permitted
• Copyright retained by author(s)

Licence dc:rights.uri

• https://rightsstatements.org/page/InC-EDU/1.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/147357

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/147357