Unmanned Systems Technology 007 | UMEX 2016 report | Navya ARMA | Launch & recovery systems | AIE 225CS | AUVs | Electric motors | Lethal autonomous weapons

6 Mission-critical info for UST professionals Platform one Swiss technology developer u-blox has launched a satellite navigation receiver module for the mass market that provides centimetre-level accuracy.  The module is aimed at unmanned aerial systems and robotics, combining a receiver for the GPS and GLONASS systems with RTK (real-time kinematic) error correction in a footprint of 12.2 x 16 x 2.4 mm. The RTK approach uses two types of module, a receiver at a known base location and one on the UAV. The u-blox NEO‑M8P‑0 is mounted on a UAV and receives corrections from a NEO-M8P-2 base receiver via a communications link that uses the RTCM (Radio Technical Commission for Maritime Services) protocol, providing error correction data that gives the centimetre-level positioning accuracy. The RTK algorithms are pre-integrated into the module. As a result, the size and weight are significantly reduced, and power consumption is five times lower than with existing solutions. RTK technologies have been used for some time in low-volume niche markets, such as surveying and construction, but a mass-market module opens up UAV applications, said Peter Fairhurst, principal engineer for high-precision products at u-blox. “For example, one use case is surveying a dam with a UAV, systematically flying across it with a camera at a fixed distance to look at cracks and so on,” he said. “Currently this is done manually from a distance with GPS at 1 to 2 m – it can’t be automated – but with centimetre-level accuracy you can control the trajectory and have the UAV automatically scan the dam without manual control and with better geotagging.” The comms link between the base and the receiver can be chosen by the customer depending on the application, with modules available for sub-GHz wireless links at 915 MHz for the US and Canada, 433 MHz for Europe and 433 MHz for China. Effective range is 10 km, as the errors from the satellite signals drift apart beyond that distance. The base module does not include an antenna, as the choice of antenna type and its position is a key part of the set-up of the base. “That will affect the level of performance, whether the accuracy is 1 cm or 10 cm, and these can vary from under $4 for a simple antenna to over $50 for a multipath one,” Fairhurst said. “A commercial UAV operator looking at getting stable flight trajectory and geotagging as accurately as possible cares about the antenna. They need to understand where the antenna is, and what the antenna phase is. “We see the mass adoption being by UAV makers developing their own base stations for the 1-10 km range. It’s about enabling a UAV manufacturer to develop a base that an operator can take with them, tied to the technology in the UAV.” Other application areas include agriculture and robotic guidance systems, such as unmanned tractors or robot lawnmowers. The module is available for sampling now and will be shipping in volumes in the third quarter of 2016. Navigation April/May 2016 | Unmanned Systems Technology Precisely for the mass market The u-blox system exploits real-time kinematic error correction to achieve its accuracy