Unmanned Systems Technology 038 l Skyeton Raybird-3 l Data storage l Sea-Kit X-Class USV l USVs insight l Spectronik PEM fuel cells l Blue White Robotics UVIO l Antennas l AUVSI Xponential Virtual 2021 report

72 In operation | Blue White Robotics Platform harnesses and processors are prioritised. The second component of the kit is the high-level computer. If automated control outputs are the front end of vehicle autonomy, this second computer is in charge of the back end. Sensors, processors and other components for perception, navigation and data comms are wired into this system. “Both the low-level and high- level computers go inside the same ruggedised box somewhere out of the way in the cab,” Ascher comments. “To provide the high-level computer with forward perception, there’s one Lidar at the front – mainly we use Ouster’s Lidars for that – but solid-state Lidar could be very interesting in the future.” Cellular as well as RF links are used to ensure consistent comms between the tractors and the operator. LTE is the standard cellular mode, although Blue White is working towards adopting 5G, having been accepted into the 5G Open Innovation Lab alongside companies such as Intel, T-Mobile and Microsoft. The RF data links enable continued connectivity for times and fields where there is no cellular infrastructure. The company declines to disclose which frequencies or antennas they operate with, however, as finding the optimal RF arrangement for consistent comms in fields (particularly under orchard canopies) has proved to be one of the hardest challenges to solve, particularly for remote farms in the US or Australia. In addition to these various electronic and electromechanical systems, a mechanical bumper kill switch is installed on the front as a safety measure of last resort if the perception and navigation systems all fail at the same time. The last component of the platform is the set of control linkages for tractor attachments such as sprayers, mowers and shredders. They consist of rugged servos and hydraulics connected to the equipment and the low-level computer for activating and deactivating them at the correct waypoints. “Tractors have to operate in harsh environments, with vibration, dust, chemicals and occasional impacts from tree branches, so we need to use ruggedised components everywhere, along with cage-like bars over some components,” says Ascher. Before a mission While software for simulating vibrations and thermal effects on components is available, Blue White opts instead for real-world trials of different parts. Its r&d team puts together different combinations of tractors, electronics and environments outside of their workshops most days to gather data on how different suites of perception, navigation, data link and other systems perform depending on the farm and fleet. “We learn from our operations and customers too,” Ascher says. “It’s crucial to get real-world feedback and data on how the components behave on real tractors with real implements in real fields.” Such test data is critical when it comes to tailoring an autonomy kit for a customer, and that bespoke approach includes the writing of algorithms and scaling of processors for handling the dynamics of different farms all year round. “For example, you might have an apple orchard with rows of trees, and for half the year their tractors run the same patterns of waypoints throughout those fields. But then pollination season comes around, and the growers have to move their beehives into those routes,” Ascher notes. “Now you have a bunch of incredibly valuable obstacles everywhere that need to be accounted for and avoided. Such seasonal changes need to be considered during the planning stages.” If a given farm is using well-known tractor models that Blue White’s engineers are familiar with, the whole integration process typically takes a few days per vehicle, plus a few days to set up the comms infrastructure around the farm. So if a grower owns six or so known tractors then typically two Blue White engineers will perform the required integration tasks over a few weeks, with a few additional weeks added if unknown tractor models are in use. “Most attachments add little or no time to integrate with our systems,” Ascher adds. “A lot of shredders and other trailers work passively behind the tractor, and as such need no electronics or mechanical upgrades. “After all the assemblies are complete, we run a final acceptance test, June/July 2021 | Unmanned Systems Technology As tractors often have to work under trees, high-end perception sensors and IMUs are critical for safely navigating during GNSS outages