Application Note
Miniature Liquid Level Sensors for UAV’s
Miniature liquid level sensors improve mission optimisation for UAVs
Mission optimisation is a key factor for both military and commercial users of Unmanned Aerial Vehicles (UAV). This could mean maximising payload, flying further or flying longer. A critical factor in mission optimisation is fuel management. Operators need precise fuel level information otherwise missions may have to be completed earlier than necessary. With some UAV’s costing in excess of $35M, losing a vehicle due to lack of fuel is not a desirable outcome.
While most manufacturers have incorporated the latest satellite communications and computer aided navigation systems into their UAV’s, fuel management is one area that has not always kept pace with technology. For example, some UAV’s use commercially available automotive sensors to manage fuel. These sensors were not designed for challenging UAV applications and as a result, the data they provide is often inaccurate and unreliable, resulting in critical missions being unnecessarily compromised.
Borrowing from the technology used in Formula 1 racing cars, Gill Sensors has developed a range of highly accurate and reliable sensors that provide the vehicle operator with precise information about fuel availability. Data provided by the new miniature level sensors can be used to increase the performance and reliability of unmanned systems, offering engineers greater scope for tactical decisions based on reliable sensor data.
The Gill Sensors range of miniature fuel, micro sensor 238x300oil and coolant level sensors incorporate micro-electronics making them especially suited to smaller unmanned systems applications. Utilising advanced solid-state capacitive technology, the integrated electronics provide a fully configurable analogue output accurate to 0.25% of the tank depth. A data logger uses the output from the sensor and the tank profile mapping to convert level into volume. Information on the actual volume of fuel available is then sent to the operator as part of the flight communications.
Each sensor is custom-designed to suit the specific requirements of the application to ensure optimum performance without the need to extensively modify existing system components. This makes the sensors equally suited to vehicle upgrades or for specification on new developments.
Keeping the overall vehicle weight to a minimum is important and the sensors typically feature titanium and carbon-fibre components to ensure that the mass of the sensor has minimal impact on the vehicle operation. Sensor length can be as little as 20mm, allowing for precision monitoring of small reservoirs.
Environmentally protected to IP68, Gill’s miniature sensors are suitable for full-submersion in aviation-grade fuel, oil or coolant and are rated for operation from -40ºC to +125ºC. Sensors can be ordered with an integral connector or flying leads, and will meet the most stringent military EMC requirements.