VectorNav has announced the successful integration of its VN-200 GPS-aided inertial navigation system (INS) into Overwatch Imaging’s TK-series precision imaging payload. This innovative payload is tailored for aerial smart mapping and automated detection tasks for both unmanned aerial vehicles (UAVs) and piloted aircraft.
Explore the complete case study >
Conventional tactical imaging payloads, such as stabilized turret systems, typically utilize electro-optical cameras with narrow field-of-view angles and significant zoom capabilities. While these systems excel at tracking targets from elevated positions, they are hindered by the “soda straw effect.” This phenomenon occurs when zooming in on small targets restricts the visible ground area, while zooming out to capture broader landscapes obscures finer details.
Stabilized “soda straw” video systems face challenges when tasked with locating small objects across expansive areas,such as during industrial inspections or extensive land management surveys.Recognizing this gap, Overwatch aimed to create imaging systems that offer an enhanced balance of image clarity and area coverage for low-altitude operations involving both manned and unmanned aircraft. To manage the influx of data, Overwatch also developed automated image processing software to convert imagery into actionable geospatial intelligence.
The TK-series camera systems from Overwatch Imaging are built around a distinctive nadir-pointing (directly downward) mount that stabilizes pitch, roll, and yaw. This system incorporates an imaging module equipped with submission-specific sensors and optics, a compact onboard supercomputer, and storage for custom image processing algorithms.
To achieve extensive coverage with high resolution, Overwatch’s engineers devised a step-stare scanning camera motion feature that quadruples the data collected per pass compared to customary mapping systems. This advancement allows users to either cover four times the ground area in a single pass, enhance resolution by four times, or a combination of both.
To implement this sophisticated imaging technique, Overwatch required an INS that could be directly mounted to the optical bench. This approach eliminates the need to depend on the aircraft’s INS for data, removes the necessity for encoders on individual axes, simplifies the control system and electronics, and results in a more compact overall design—crucial for small and medium-sized UAS. Additionally, it was essential for the INS to deliver low-latency attitude data with an accuracy of 0.1° for pitch and roll under dynamic conditions. This capability streamlines workflows, reduces the processing burden for real-time image stitching, and facilitates operations at greater standoff distances.
After evaluating various inertial products from multiple suppliers, Overwatch’s engineering team prioritized finding a solution that offered the highest accuracy in the smallest form factor at the best price. The vectornav VN-200 Rugged GPS-aided INS excelled in all these aspects. Its ability to provide precise position and attitude data at rates of up to 400 Hz,along with a high gyroscope angular rate range (±2000 °/s),enabled the TK-series to maintain accurate attitude estimates during the step-stare scanning maneuvers.
“VectorNav is highly regarded in the industry,” stated greg Davis, Founder of Overwatch Imaging. “When we assessed the available options, it became evident that the VN-200 outperformed other INS solutions in terms of size, cost, and performance, making our decision straightforward.”
The TK-series payloads can be tailored with various combinations of cameras, filters, and lenses to achieve optimal spatial and spectral resolution for specific data collection and automated image processing needs. A significant advantage of overwatch’s business model is its ability to swiftly develop and commercialize these custom systems, a process greatly facilitated by the VN-200. “Setting up the VN-200 was straightforward; it functioned almost immediately,” Davis remarked. “The VN-200 also features a user-pleasant external GPS option, allowing us to accommodate a range of customer-requested external GPS systems.”
The VN-200 is integral to the TK-series payloads, supplying essential data for platform stabilization, roll sweeping, step-stare functionality, and precise geolocation of target objects, distinguishing the TK-series from its competitors. In October 2016,Textron Systems announced the integration of Overwatch Imaging’s TK-7 Firewatch,featuring the VN-200,into the Aerosonde Small UAS. The TK-7 Firewatch is equipped with multi-megapixel color focal plane arrays and co-boresighted infrared sensors, enabling the system to automatically identify anomalies, such as hotspots for wildfire monitoring. This capability allows wildland fire teams and forest health managers to effectively oversee vast areas, providing critical analysis, reporting, and rapid response capabilities.
Overwatch Imaging’s TK-series is being deployed in a wide array of applications, ranging from vegetation management and infrastructure inspection to automated target detection and geolocation.
