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This article presents the core technologies and deployment strategies of Team CERBERUS that enabled our winning run in the DARPA Subterranean Challenge finals. CERBERUS is a robotic system-of-systems involving walking and flying robots presenting resilient autonomy, as well as mapping and navigation capabilities to explore complex underground environments.

In this research, we propose a novel concept for a non-destructive evaluation of volatiles emitted from ripening grapes using solid-phase microextraction (SPME). This concept is novel to both the traditional vinifera grapes and the cold-hardy cultivars. Our sample models are cold-hardy varieties in the upper Midwest for which many of the basic multiyear grape flavor and wine style data is needed. Non-destructive sampling included a use of polyvinyl fluoride (PVF) chambers temporarily enclosing and concentrating volatiles emitted by a whole cluster of grapes on a vine and a modified 2 mL glass vial for a vacuum-assisted sampling of volatiles from a single grape berry. We used SPME for either sampling in the field or headspace of crushed grapes in the lab and followed with analyses on gas chromatography-mass spectrometry (GC-MS). We have shown that it is feasible to detect volatile organic compounds (VOCs) emitted in-vivo from single grape berries (39 compounds) and whole clusters (44 compounds). Over 110 VOCs were released to headspace from crushed berries. Spatial (vineyard location) and temporal variations in VOC profiles were observed for all four cultivars. However, these changes were not consistent by growing season, by location, within cultivars, or by ripening stage when analyzed by multivariate analyses such as principal component analysis (PCA) and hierarchical cluster analyses (HCA). Research into aroma compounds present in cold-hardy cultivars is essential to the continued growth of the wine industry in cold climates and diversification of agriculture in the upper Midwestern area of the U.S.

The Midwest wine industry has shown a marked increase in growers, hectares planted, wineries, and wine production. This growth coincides with the release of cold-hardy cultivars such as Brianna and Frontenac gris, in 2001 and 2003, respectively. These white grape varieties account for one-third of the total area grown in the state of Iowa. It is generally accepted that the wine aroma profile plays a crucial role in developing a local, sustainable brand. However, the identity of Brianna/Frontenac Gris-based wine aromas and their link to the grape berry chemistry at harvest is unknown. This study aims to preliminarily characterize key odor-active compounds that can influence the aroma profile in wines made from Brianna and Frontenac gris grapes harvested at different stages of ripening. Brianna and Frontenac gris grapes were harvested approximately 7 days apart, starting at 15.4 °Brix (3.09 pH) and 19.5 °Brix (3.00 pH), respectively. Small batch fermentations were made for each time point with all juices adjusted to the same °Brix prior to fermentation. Odor-active compounds were extracted from wine headspace using solid-phase microextraction (SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS) and simultaneous olfactometry (O). Over 30 odor-active compounds were detected. Aromas in Brianna wines developed from "cotton candy" and "floral", to "banana" and "butterscotch", then finally to "honey", "caramel" and an unknown neutral aroma. Frontenac gris wines changed from an unknown neutral aroma to "fruity" and "rose". Results from the lay audiences' flavor and aroma descriptors also indicate a shift with harvest date and associated °Brix. To date, this is the first report of wine aromas from Brianna and Frontenac gris by GC-MS-O. Findings from this research support the hypothesis that aroma profiles of Brianna and Frontenac gris wines can be influenced by harvesting the grapes at different stages of ripening.

There has been considerable public interest and a growing number of scientific studies linking certain phenolic compounds in grapes and wines, particularly trans-resveratrol (trans-3,5,4'-trihydroxystilbene, TRA), to human health benefits. Typical TRA concentrations in wine are very low. It is a polar compound with very low volatility, which makes it difficult to extract and to separate on a gas chromatography (GC) column without derivatization. In this study, a new method for trace analysis of TRA was developed using solid-phase microextraction (SPME) with on-fiber silylation derivatization. Multidimensional GC equipped with a heartcut valve and cryogenic focusing was coupled with a mass-selective detector and used for improved separations and analysis. The effects of SPME fiber selection, extraction time, temperature, and desorption time were investigated. The derivatization conditions, time/temperature and the volume of derivatization reagent were also optimized. The calibration curve was linear over the concentration range from 10 ng L(-1) to 5 mg L(-1), with a correlation coefficient of 0.9996. The average recovery of TRA in red wine was 83.6+/-5.6%. The method detection limit (MDL) for TRA in ethanol:water (12.5:87.5, v/v) solution in this study was 7.08 ng L(-1) whereas the MDL for TRA in pure water was 2.85 ng L(-1). The new method was used to test the TRA content in six selected Iowa red wine samples. Measured concentrations varied from 12.72 to 851.9 microg L(-1).