Drones have recently been introduced in a variety of scenarios. Amendments to the Civil Aeronautics Law and its enforcement have made it possible to conduct 'unobserved flights in manned areas = Level 4' from December 2022. Their use is expected to expand further, but one of the challenges is flight time. Currently, most flights last for 20-30 minutes, and there is a need for even longer flights. Robodex Corporation (President: Daisuke Kaiou, Asahi-ku, Yokohama) is attempting to overcome this barrier with fuel cells using high-pressure hydrogen. The company's drones have already achieved flights of over 80 minutes. 

 

From Robodex HP

 

The company was established in June 2019. President Kaiou went independent after becoming attracted to the potential of drones from an engineer at a manufacturer, and has experience in obtaining six patents related to drones and robots, as well as developing an early drone school nationwide. He then established the company with the intention of specialising in the development and manufacture of drones for industrial use. So far, they have modified existing models from other companies and built a hybrid drone that can carry more than 30 kg in a two-hour flight on electricity generated by a petrol engine, but their main focus is on fuel cell drones that use high-pressure hydrogen. As a "hydrogen drone pioneer", the company has been involved in development since its establishment and completed the Aigis One, which was designed and manufactured by the company, in June 2022.

 

The main unit weighs 15 kg, has a payload of 5 kg and can fly for up to 120 minutes. The box-shaped fuselage has a 4.7 l cylinder at the top, and the hydrogen in the cylinder reacts with the fuel cell below the cylinder to generate electricity to power the vehicle. The cargo is carried in a container at the bottom of the aircraft. Some people may be worried whether it is safe to fly in the air with cylinders filled with hydrogen, which do sometimes explode. However, the aircraft has received special ministerial approval to ensure that hydrogen does not leak even if dropped from a height of 150m. "You see the oxygen cylinders that firefighters carry on their backs? Think of it as being as robust as those," says president Kaiou. It is made by Teijin Engineering and has excellent safety features. The fuel cells are from Intelligent Energy of the UK. In addition, it is equipped with JTEKT capacitors to provide the high-power output required for rapid ascent, for example. 

 

Aigis One, test flight at Fukushima Robot Test Field. (Courtesy of Robodex)

 

The hydrogen gas pressure in the cylinder is 19.6 megapascals. The cylinder itself can handle up to 29.4 megapascals, but the Japanese standard is 19.6, and if the system changes in the future to allow up to 29.4, the cruising range can be extended further.

　

The head office in Asahi-ku, Yokohama, is positioned as the "Yokohama Lab" and is located in a building along the Hodogaya Bypass. The basement room is a real workshop, with pipe-framed shelves lined with various drone components and tools, between which employees work on desktop computers. There are also several 3D printers, where the drones are actually manufactured. In addition to this facility, there is a Fukushima Lab at the Fukushima Robot Test Field in Minami Soma City, which was established by Fukushima Prefecture, and a test airfield in Kayakisaki City, Kanagawa Prefecture. President Kaiou and his employees move back and forth between these locations, working day by day to improve the performance of their drones. 

 

Yokohama Lab

 

Yokohama Lab, President Kaiou looking at his drone.

 

Hydrogen is the key. Fuel cell drones, which emit only water no matter how far they fly, are an excellent means of transport for achieving carbon neutrality in the future, but at present there are few hydrogen filling facilities which is a disadvantage. However, a major step forward in the future may be the FH2R hydrogen production facility built by NEDO, Toshiba Energy Systems, Tohoku Electric Power and Iwatani Industries in Namie-cho, Fukushima Prefecture, near Fukushima Lab, which will be completed in March 2020 and will produce 1,200 m3 of hydrogen per hour using solar power. In December 2022, the Fukushima Hydrogen Filling Technology Research Centre also started operating on an adjacent site. Against the backdrop of these developments, President Kaiō commented: "The stage is being set to realise the ideal of fuel cell drones flying on green hydrogen. We will do our best to develop an aircraft that can carry 5-10 kg of cargo and fly for 5-6 hours", he said, expressing his determination to achieve this goal.

 

 

（IRuniverse Shinji ABE, translated by Marcin）

 

Related articles