Metrology-assisted Robotic Mirror Alignment for Parabolic Trough Collectors

Parabolic trough solar collectors are well-suited to generating industrial steam, and their efficiency at making steam is a direct result of the precision with which they are assembled. State-of-the-art designs required placement of dozens of mirror panels to sub-millimeter accuracy so that the reflected light hits its target. That painstaking placement is performed today by extensive labor and expensive, non-mobile fixtures that result in high costs. Our mobile, automated assembly method, derived from recently developed aerospace techniques, lowers costs, improves safety and quality, and can be easily moved to new project construction sites. The cost savings achieved through the proposed automated assembly method is essential to achieve a cost of industrial heat consistent with the stated SunShot thermal goal of 1.5¢/kWh. The mirror panels are positioned and fastened to sub-millimeter accuracy using industrial robots guided by advanced optical metrology. This system is installed on a mobile platform that travels across the solar field. In Phase I we will demonstrate the feasibility of our approach through a combination of design, costing, and outdoor tests. Together, this work will address the key risks associated with metrology-guided robotic assembly for solar collectors, thereby substantially extending the methods used in aerospace assembly to an outdoor, mobile, environment.