SBIR Phase II: Force-Controlled Robotic Arm Capable of Sub-Millimeter Precision

This Small Business Innovation Research (SBIR) Phase II project proposes a portable, interactive Coordinate Measuring Machine (CMM) for geometric data collection consistent with statistical sampling of a series of parts. The innovation exploits a characteristic of cable drives that supports precise repeatability in an articulated arm. To optimize production and avoid scrap generation, manufacturing process corrections must occur promptly and yet must be based on adequate measurement data. Existing metrology systems inhibit these preferred statistical process control principles. Large motorized CMMs are either taught offline using computer-aided design (CAD) models or online using awkward joystick interfaces. Manual-only portable-arm CMMs are safe and convenient to use, but teach-and-playback is not supported. The proposed solution is a motorized articulated robot that combines the safety of a manual system with playback precision thereby supporting convenient statistical process control (SPC). The research objectives are to design and build a motorized CMM and develop the algorithms, tools, and procedures needed to create a successful product. The anticipated commercialized product will be a portable, user-friendly, cost-effective robotic arm that spreads the quality advantages of statistical process control across a broad range of products and manufacturers including non-traditional manufacturing such as medical surgery. The broader impact/commercial potential of this project has four parts. The first is the direct impact on the US economy. US workers will assemble, test, and ship the products developed under this SBIR. Components will be sourced from local US fabricators and OEM suppliers, boosting the US economy and generating taxes; and some of these products will become exports, reducing the US imbalance of trade. Secondly, the shortcomings of metrology devices available today discourage the use of statistical process control, thereby undermining manufacturing quality. The proposed solution will improve manufacturing competitiveness in the metrology market sector through easier adoption of statistical process control, leading to higher quality and reduced scrap costs. Thirdly, the proposed solution invites production-line workers back into close physical contact with the process that they must ultimately understand and control. The worker strengthens intuition by teaching the device for each new part geometry, while the playback capability avoids tedium and repetitive stress. Corporations often automate these workers out of their skilled jobs who then join the unemployed while the company loses touch with the ability to understand and innovate processes. Finally, this SBIR will support formal internship programs with several universities in order to maintain diversity.