Redundant IMU sensors for UAS inertial navigation
Unmanned systems and UAS join measurement data from different sensors to get an accurate navigation. The main sensors used are: IMU (Inertial Measurement Unit), GPS (Global Positioning System) and barometers. At the same time, the IMU embeds different sensors to add inertial data to the navigation. These IMU sensors allow to improve flight operations and the positioning estimation of the aircraft, permitting to perform missions with UAVs and other unmanned systems where precision is a key element.
Usually it is assumed that GPS sensors are the ones on charge of the biggest part of the navigation work, but sometimes they lose the GPS signal. For this reason, when there is no GPS signal, the precision of IMU sensors gets the main role, allowing to perform inertial navigation. IMU sensors usually are made of accelerometers and gyroscopes, which are sensitive to pitch, roll and yaw rotations. Obtained data by IMU sensors provide the autopilot with measurements that allow the estimation of the UAS position, permitting to continue the mission even without GPS thanks to the inertial navigation.
Relevant aspects of Veronte Autopilot redundant IMU
Veronte Autopilot embeds redundancy in its IMU, resulting on the availability of two independent units for navigation that provide an increased reliability and performance. The main advantage of having a redundant IMU is that data from two different IMUs in the same system allows Veronte Autopilot to include extended corrections of the positioning and orientation of the vehicle, improving the estimation of the position of the GPS sensor.
This high performance IMU allows to carry out any kind of mission. With a speed data transmission up to 1 kHz from the IMU to the processing unit of Veronte Autopilot, it can be configured to obtain an optimized precision, admitting the optimized calibration for spins up to 2000 º/s and accelerations in continued maneuvers up to ± 16 G. This means that its precision is especially high, either for small multirotors at low speeds of around 30 km/h, and for guided missiles and unmanned aerial targets at speeds over 1000 km/h.
Due to the precise calibration of the IMU, the system is robust on flights without GPS, keeping continuously the aircraft attitude with a deviation on the position good enough to maintain a stable flight until GPS signal is recovered. Veronte Autopilot has a great calibration data persistence and a reliability especially high on its components, resulting on a great resistance to hits and the passing of time. IMU calibration can be done through some easy steps from the control software Veronte Pipe.
For those cases where the redundancy on the IMU and GPS sensors are not enough, the redundancy of the 4x Redundant Veronte Autopilot is the best option.