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

Barrett Technology Inc, Newton MA

Investigators

Abstract

This Small Business Innovation Research Phase I 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 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. The anticipated final 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 shortcomings of metrology devices available today discourage the use of statistical process control, thereby undermining manufacturing quality. The proposed solution improves manufacturing competitiveness by enabling easier adoption of statistical process control, leading to higher quality and reduced scrap costs. 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. This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).