Unmanned Systems Technology 017 | AAC HAMR UAV | Autopilots | Airborne surveillance | Primoco 500 two-stroke | Faro ScanBot UGV | Transponders | Intergeo, CUAV Expo and CUAV Show reports

70 Digest | Faro ScanBot UGV one at the front and one at the back, to detect movement and obstacles, and stop the robot if anyone gets close. This is also important as the scissor lift could hurt someone when it’s moving. The Lidar sensors may be appropriate for safety reasons, but for accurate indoor navigation a 3D camera is required. “For example, a laser can see the legs of a table and would steer between them, but a 3D camera can see the top of the table and know that it cannot go that way,” Santos explains. The challenge is that low-cost 3D depth sensors such as Microsoft’s Kinetic that use ‘time of flight’ measurements are not accurate enough, and stereo cameras such as those from Stereolabs generate large amounts of data that need a high-performance graphics processor that consumes a lot of power. All of this has to be handled in real time as well. “We want everything in real time, so we still need to find a solution for that,” Santos says. “It’s about the technical details, so we have to achieve a compromise in the price of the ScanBot – if we start adding sensors to solve every issue we increase the price of the system. Also, these cameras do not work so well outdoors so we want one that works well outside.” The data from the SLAM software is used to create a 3D map of the environment by combining the data from the Lidar and 3D camera, and the system then computes the best path to each scanning point. All of that is handled on board. Software development The central controller is a standard PC board using an Intel Core i7 processor running Linux. Faro has developed its own real-time software, using the libraries supplied by the various component suppliers for onboard systems such as the wireless comms board and the lift controller. “Even for the small controller for the scissor lift the manufacturer provides the libraries, and we use a commercial actuator,” Santos says. The central controller sends velocity December/January 2018 | Unmanned Systems Technology Early scissor lifts proved not to be up to the task of supporting the 1.5 kg camera