Chris Vermillion Assistant Professor
University of North Carolina at Charlotte Department of Mechanical Engineering
and Engineering Science 9201 University City Blvd. Charlotte, NC 28223-0001
U.S.A. cvermill@uncc.edu coefs.uncc.edu/cvermill
Development of a Micro-Scale Closed-Loop Testing Framework for Airborne Wind
Energy Systems – A Case Study in University/Industrial Collaboration
Chris Vermillion
University of North Carolina at Charlotte Researchers at the University of North Carolina at
Char-lotte, University of Michigan, and Altaeros Energies have collaborated over three years to create the first 1/100-scale platform for closed-loop flight characterisation of airborne wind energy systems. This platform, which utilises a water channel and 3D printed AWE lifting body models to replicate full-scale flight dynamics at 1/100-scale, has evolved from a manually-adjustable, passive system (described in [1], [2]) to a closed-loop system where positions and orientations are computed through real-time image processing and tether lengths are con-trolled via micro DC motors (first illustrated in [3]). The original platform was successfully used in the design of Altaeros’ 2013 prototype, which exhibited stable flight at 10-15 m/s sustained wind speeds and gusts up to 21.2 m/s (see [2]). The current platform is being used to per-form rapid experimental iteration between different lift-ing body and control system designs. This iterative pro-cess is being utilised by Altaeros Energies and is being explored at a more fundamentally mathematical level at UNC-Charlotte, where researchers are investigating opti-mal techniques by which experiments can be fused with numerical design optimisation.
This presentation will review the capabilities of the exist-ing water channel platform at UNC-Charlotte, as well as the scaling analysis that provides guidance for designing the 1/100-scale models and control parameters to repli-cate full-scale flight properties. The presentation will demonstrate, through test data and videos, the use of the
water channel to perform iterative design. The presen-tation will also describe a mathematical framework for optimally fusing these experiments with numerical mod-elling.
In addition to serving as a valuable iterative design tool, the 1/100-scale platform serves as a case study in collab-oration between multiple universities and an early-stage company, which operate on different timelines and have different intellectual property (IP) interests. In addition to providing a technical description of the experimental platform, this presentation will illustrate how the enti-ties involved have worked together to (1) identify techni-cal objectives that were related to both short-term first-to-market interests and long-term research interests and (2) identify confidentiality boundaries that satisfied the company’s need for secrecy and university’s need to pub-lish.
References:
[1] Vermillion C., Glass B., Greenwood S.: Evaluation of a Water Channel-Based Platform for Characterizing Aerostat Flight Dynam-ics. Proceedings of the 2014 AIAA Lighter-Than-Air Systems Confer-ence, Atlanta, GA, 16–20 June 2014
[2] Vermillion C., Glass B., Szalai B.: Development and Full-Scale Ex-perimental Validation of a Rapid Prototyping Environment for Plant and Control Design of Airborne Wind Energy Systems. Proceedings of the ASME Dynamic Systems and Control Conference, San Antonio, TX, 22–24 October 2014
[3] Deodhar N., Vermillion C., Tkacik P.: A Case Study in Experimentally-Infused Optimization for Airborne Wind Energy Systems. Accepted for presentation at the American Control Con-ference, Chicago, IL, 1–3 July 2015
