BMT has been granted a new patent by the UK Intellectual Property Office for a novel concept called ‘SPARROW’, an autonomous ‘air-ground payload transfer device’ with truly disruptive capabilities for drone delivery applications.
“BMT’s patent signals a new type of suspended robotic device: a device that takes over responsibility for the final moments of payload delivery, and better suited to challenging and sensitive environments. This small, highly-ruggedized robotic device could even autonomously collect packages as well as deliver them without the need for infrastructure on the ground,” said Phil Metcalfe, Regional Business Director for UK and Europe. “With the development of this autonomous and highly-versatile concept the project team have delivered a great example of how BMT actively applies its innovation to solve its customers’ complex problems. Further, we were super excited to participate in the British Army’s Army Warfighting Experiment (AWE) 23, with our rugged technology demonstrating the potential to feed into the army’s plans for a future digital backbone.”
The AWE 23 independent Product Assessment Report cited the following: “As the system is developed further, it will provide a capability unlike anything else known to Defense. It would enable the use of UAS to deliver payloads in the most challenging terrain, reducing risk to both the airframe, the payload and personnel on the ground.”
With SPARROW, BMT believes it has addressed the inherent problem of large, noisy, and potentially hazardous delivery drones having to land or hover low over the payload destination, potentially close to people in unpredictable, sensitive and cluttered environments.
According to BMT, SPARROW is fundamentally different to winch systems commonly used in current trials for delivery drones. On a winch, the payload swinging at the bottom end of a line is raised or lowered by the cable drum attached to the underside of the fuselage, and moved horizontally by subtle movements of the drone above. This provides poor control of the payload, especially in windy conditions and limits the maximum height of the drone.
In comparison, SPARROW is located at the bottom end of the line with the payload with its own power, sensors and actuators; it has autonomous control of its descent using an internal drum, while making precise and immediate horizontal adjustments to counter wind effects using four small, quiet pusher fans. SPARROW takes responsibility of the delivery allowing the larger delivery drone to remain much, much higher at the destination, relatively unheard and unobtrusive at ground level.
Being much smaller than the drone and without the need for powerful, lift-generating rotors, SPARROW enables safe, precise and quiet delivery in challenging or sensitive environments.
BMT’s development partner, Dr Steve Wright from Wright Airborne Computing, said: “During 30 years of working in aerospace, I have not seen anything like the surge in new aircraft, systems, and applications that has happened in the last five years. SPARROW is a perfect example of this revolution, fuelled by a happy convergence of 21st century technologies harnessed together by computers and software that engineers like me could only dream about 30 years ago.”
Replacing a traditional drone-mounted winch, BMT’s novel robotic device uses a ‘system of systems’ approach. The autonomous SPARROW lowers both itself and the payload at the bottom end of a long, low-profile, weight-bearing line, with the top end of the line attached to the drone above. To provide autonomy of movement, SPARROW has an internally powered cable drum to silently control height, four small side-facing pusher fans for horizontal adjustments, and all the necessary sensors, power, and processing.
The SPARROW concept enables the large, noisy, vulnerable drone to remain much higher above the complex ground environment at the destination. Safe controlled delivery is possible using this approach from 200ft in windy conditions, and 500-1000ft in light winds, with additional options for higher drops. In comparison to using a traditional winch from a low hover, a SPARROW delivery offers a smaller, quieter physical presence and a safer, more precise delivery to a wider variety of locations, including confined spaces close to vertical surfaces and urban infrastructure.
Alongside applications in Defense, the approach may also offer value to manned helicopter operations and across other sectors such as Maritime Ship-Shore deliveries, support to maintenance engineers on tall structures, Emergency Services, and e-commerce deliveries to domestic addresses. The project is looking to partner for further Research and Development and licence the technology to a range of leading established operators.