Unmanned Systems Technology 022 | XOcean XO-450 l Radar systems l Space vehicles insight l Small Robot l BMPower FCPS l Prismatic HALE UAV l InterDrone 2018 show report l UpVision l Navigation systems

Aceinna, a spin-off from sensor maker MEMSIC, has developed a professionally supported, open-source inertial navigation software stack and hardware module for navigation applications (writes Nick Flaherty). “Our open-source software for INS/GPS algorithm development is the first professional-grade open-source navigation stack running on a low-cost IMU,” said Mike Horton, CTO of Aceinna. “We are trying to take it easier to take a calibrated IMU and put it to work.” The OpenIMU uses a 32-bit 180 MHz microcontroller from STMicroelectronics with libraries of key source code software available on Github. This includes a real-time operating system based on the open-source FreeRTOS code as well as a real- time, navigation-grade GPS/INS Kalman filter library. “It’s the code we’ve been using for years in our Crossbow IMU products, when that was acquired by MEMSIC, so it has thousands of flight hours,” said Horton. “There’s a complete set of documents on the practical implementation of high-quality IMU Kalman filtering that evolved from Crossbow to correct errors in roll, pitch and heading, and errors in the bias of the module. The Kalman filters can correct for all of that by compensating for the errors in the sensors – it mathematically handles all that.” A key difference from other open-source implementations is a robust simulation environment using the Python language with advanced sensor error models. The OpenIMU module features Aceinna’s 5 º /h, nine-axis gyro, accelerometer, and magnetometer sensors in a module measuring 24 x 37 x 9.5 mm; it runs on 2.7-5.5 V DC.  Navigation Open-source INS stack The OpenIMU is designed to make it easier to take a calibrated IMU and put it to work