Issue 41 Unmanned Systems Technology December/January 2022 PteroDynamics X-P4 l Sense & avoid l 4Front Robotics Cricket l Autonomous transport l NWFC-1500 fuel cell l DroneX report l OceanScout I Composites I DSEI 2021 report

58 It is unsurprising then that more than a few companies are developing efficient, large-scale, waterborne public transport services, and in the 21st century, going for scale and efficiency means going for autonomy. One of the companies furthest along in the development of autonomous ferries is Callboats, in Finland, which began its r&d in 2017 to create a small-scale prototype vessel called the CAT-6. That ran in commercial trials in Helsinki in 2020, and the lessons learned from that have now been fed into the larger CAT- 10, which Callboats intends to use as its production model. “I believe we’re the first to have launched a service like this, so there have been no models to follow – getting real-world testing data has been really important,” Peter Ostberg, managing director at Callboats, says. “Effective water transport these days is nearly non-existent. There are traditional water taxis, which are usually very expensive for individual passengers, and the only alternative are ‘scenic route’ ferries, which are docked in inconvenient locations and run for very limited hours and only few times a day.” The CAT-10 has thus been engineered to be as energy-efficient as possible, to pose a far more cost-effective alternative to both these options as well as road transport. The system is all-electric, to prevent the noise and harm to health of running on diesel. It has a 1.2 kW roof-mounted solar panel that recharges two 30 kWh lithium- ion battery packs (although 8 kW three- phase plug-in charging can also be used). That and the solar roof give about 16 hours of operation. Most of the energy is supplied to four 10 kW pod thrusters for propelling and steering the 4 tonne, 12-seater ferry at a cruising speed of 6 knots; there is enough standing space for an extra eight passengers. The boat itself is made from aluminium for optimal manufacturability and recyclability. Autonomy is achieved by following predefined routes with a combination of vision and Lidar sensors about the hull for obstacle detection, and a remote operating centre will oversee the activities of a given fleet for added safety. “It’s a catamaran, and each hull is independent from the other for redundancy. If one motor or battery has a fault we can keep running smoothly on the other, and then we’ll slow-charge them overnight to prolong battery life and minimise electricity costs,” Ostberg explains. “We want to offer this boat as an on-demand service, so we have a smartphone app and the boat is designed with a ramp to dock at any pier from 20 to 150 cm in height. Docking stations are not needed, and the boats do not require any new infrastructure. “And we aim to reduce the transport industry’s operating costs, both in energy terms and – through our Nvidia TX2-powered autonomy – being able to hire drivers who don’t need years or months of training to start working for us, and won’t become stressed by the burden of captaincy.” Elsewhere, and earlier this year, autonomy company Buffalo Automation partnered with the Future Mobility Network and Next Generation Shipyards to launch its electric robotaxis as a service in the Netherlands. “We did our first launch in Warmond, with our Greycraft all-electric autonomous water taxi serving to carry passengers between the golf courses and marinas there,” CEO Thiru Vikram says. “Now that summer in Europe is over, we’ve wrapped up those operations, but next year we’ll launch a number of Greycraft services in Rotterdam, Amsterdam and other dense metropolitan areas where people are already using waterways to get around.” The company’s facility in Knoxville, in the US, is used for r&d, with some data having been accrued from Warmond, although that launch was mainly a commercial venture rather than for research. To create a stable, introductory platform for autonomous water transport, particularly among customers new to boating, Greycraft has been built as a low-speed, dual-pontoon electric system. A roof provides shelter for passengers as well as a mounting point for solar cells, and the multi-hull configuration helps to spread and maximise the surface area of the roof to provide extra space for solar charging. Notably, the Greycraft uses AGM-type deep-cycle marine batteries rather than lithium-ion packs, a decision made to better ensure that the solar panel can continue recharging the batteries at below- freezing temperatures without expending energy on heating them. “We want anyone to be able to operate and maintain these boats. You can walk December/January 2022 | Unmanned Systems Technology The CAT-10 USV from Callboats will initially provide on- demand transport around Helsinki (Courtesy of Callboats)