Project description

Residual stresses are present in many materials. Measuring residual stress in materials is a very precise process. There are several semi-destructive methods for measuring residual stress including hole-drilling and ring-coring. These methods require a cutting tool to be oriented perpendicular to the surface of a specimen for accurate residual stress measurement results. The existing device used for hole-drilling and ring-coring measurements at Hill Engineering incorporates a manually operated system capable of two rotational degrees of freedom such that the end of the cutting tool is oriented normal to the specimen surface.

This project will involve design, construction, and validation of a device to automatically rotate a cutting tool to be perpendicular to the surface of a test specimen. There shall be minimal operator action required for alignment. The system shall operate in any orientation (i.e., mounted at up to 180-deg from horizontal) and shall be rigid and capable of holding up to 40 lbs in any orientation. When mounted, the system shall have the capability to rotate up to +/- 10- deg and should be capable of resolving 0.1-deg of rotation over a length of 12 mm. Additionally, the system should be capable of at least 75 mm of translation parallel to the cutting tool axis. After adjustment, the system must stay locked in place +/- 5 m. The system shall fit within a volume of 300 mm (L) x 300 mm (W) x 200 mm (H), shall have sufficient open space to fit a cutting tool (details to be provided) and shall weigh less than 20 lbs. A software interface is required to operate the alignment system. The software should allow for automatic alignment as well as manual control of the system.

The project involves the following tasks:

• Define device capabilities: interact with company engineers to finalize the detailed requirements
• System design: identify candidate design approaches, weigh tradeoffs, and select final design
• Critical design reviews: present design to company for feedback and acceptance
• System prototype: prepare detailed system drawings, machine and manufacture components, assemble, develop software and control
• System validation: validate the performance of the device
• System documentation: provide design information and operation instructions
• Demonstration and training: provide on-site system demonstration and training