What technology is used by the specialized large drone that contributes to increased safety and reduced workload in response to the forestry worker shortage?

Japan is one of the world’s few woodland countries with forests covering about 67% of the land. Many animals live in these woods, and they are home to diverse ecosystems. The forestry industry aims not just to produce wood products using timber from these woods but also to preserve the ecosystems and natural environment. As a forest grows, it gives rise to rich woodland ecosystems, and in addition to absorbing CO₂, a major cause of global warming, trees with their deep roots also prevent landslides and are essential for protecting the land in which we live.

However, the forestry industry is currently facing a severe labor shortage due to the impact of the aging society and other factors. In addition, it is difficult to ensure worker safety.
In response to these issues, attention has turned in recent years to the use of drones to support forestry work. For example, large drones can be used in place of people and helicopters to carry cargo into locations inaccessible by vehicle, thereby increasing work efficiency and reducing costs.

Furukawa Sangyo, a member of the Furukawa Electric Group, possesses experience and know-how in drones while conducting sales as its main business.

Furukawa Electric and Furukawa Sangyo partnered with Shimane Prefecture in 2021 with the aim of contributing to solving the issues facing the forestry industry by utilizing the accumulated know-how in drones through a “project for reducing forestry workload” involving the transportation of saplings. The following year in 2022, the companies partnered with Misato Town to begin a “forestry innovation project” involving the transportation of materials for preventing animal damage.

Misato Town, the site of both projects, is located in a mountainous area of Shimane Prefecture, and it is experiencing acute population decline. At the same time, the municipality is actively introducing cutting edge initiatives using digital and other technology in workplaces including education and nursing care. In addition, there is extremely active communication between residents. The town has been working with Furukawa Electric since 2020 to use AI to prevent animal damage and for disaster prevention and mitigation, and it has been an important partner who provides various feedback and proposals.

Given this background, the town became an important site for adapting Furukawa Sangyo’s experience and knowledge in inspection, measurement and transportation using drones to the forestry industry.

In the trial, Furukawa Sangyo’s specialized large drone was used to transport saplings and other materials (materials for making a wire ropeway and to prevent animal damage) to steep hillsides and other locations not easily accessible by vehicle.

Typically, when carrying materials by hand to inaccessible locations in mountainous areas, it is necessary to hike up mountain trails fully loaded with gear, which is extremely hard work. Also, transporting cargo with a helicopter is not economical unless several tons of cargo is transported, making it a difficult option in terms of cost.

On the other hand, using the specialized large drone, it is possible to make a round-trip flight of about 350m in 3 minutes. This greatly reduces the transportation time and workload, and it is also expected to contribute to solving other issues such as increased worker safety.

In the current trial, Furukawa Sangyo focused on a “safe, secure drone that can be used in actual worksites”.

When using a drone in an actual forestry setting, it is not enough simply to be able to lift heavy cargo. The drone must also have the durability and ability to fly multiple long-distance round-trips each day while loaded with hanging cargo. In order to carry out this work more safely, it was necessary to increase airframe performance and optimize the operating parameters.

To better support such “sustainable operations”, the specialized large drone used in the trial was equipped with two main functions not found on previous drones.

The first function was “automatic calibration”. Normally when operating a drone, it is necessary to calibrate the drone to ensure the internal compass correctly points to magnetic north by rotating the drone to the left and right in a test flight.

However, performing this with a large specialized drone measuring 3m wide and weighing more than 30kg requires relatively wide-open space with few surrounding obstructions. In addition, it involves three or more people rotating the drone by hand, so there were also issues in regards to workforce.

In response to this, Furukawa Sangyo worked with a partner company and utilized the knowledge accumulated through drone development to equip the drone with technology for performing automatic calibration during a test flight. This contributed both to reducing on-site workload and increasing safety.

The second function was cargo “sway prevention”. The specialized large drone flies at a speed of 6 m/s more than 10m in the air with the cargo hanging below. When the drone stops moving, the cargo starts to sway back and forth, making it difficult to accurately land the cargo onto the ground.

The drone operator typically resolved this issue by moving the drone forward, back, left and right to limit cargo swaying and hovering in place until the cargo stops swaying. However, when flying long distances, the operator cannot visually confirm the status of cargo swaying, requiring the operator to possess advanced drone control skills. Also, the time loss that occurs due to hovering prior to landing the cargo was also an issue.

Given this, Furukawa Sangyo’s partner company equipped the specialized large drone with an independently developed vibration suppression function. This function automatically moves the drone to suppress cargo swaying likely to occur when transporting cargo and stopped the swaying in about 1.5 movements, thereby reducing operator burden when landing the cargo.

In this way, during the approximately 2-year trial conducted at Misato Town, efforts were made to improve the specialized large drone. While listening to the feedback and requests from the forestry workers, several hundred test flights were made, and through improvements to drone performance, it was possible to successfully develop a drone that reduces worker burden and an operating method suited to the workplace environment.

In order to establish an operating system in the future that will enable on-site forestry workers to sustainably operate the specialized large drone without developer support, active initiatives are underway to train operators targeting members of the local community and provide drone operational support by local companies.

This current trial is not the end of our efforts. Going forward, Furukawa Electric Group will continue the cycle of “identify the next issue and make improvements” using the latest technology, and we will aim for further advancement and growth, including our partners, as we continue to challenge forestry DX.

The current specialized large drone also has the potential to be used in various industries outside of the forestry industry, including maintenance of steel structures in the electric power industry and transporting heavy cargo outdoors in the agriculture, construction and civil engineering domains.

Furukawa Electric Group is a long-time supplier of product lineups that support social infrastructure, including power cable and optical fiber and cable products. However, the environmental issues and other events in the past few years have started to rattle the safety and security of society, and we believe it is more important than ever to solve these issues.

For example, drones can be used to transport cargo to areas that have been cut off from the larger region during a disaster. In fact, a request was received from Misato Town to use the drone to carry water for disaster prevention.

Currently, Furukawa Sangyo offers small and medium-size drones capable of carrying 15kg, 24kg, and 40kg loads. Going forward, in line with customer demand, the company plans to provide even more thorough service. In order to realize a future in which drones are utilized in a wider range of domains, we will work to deepen the partnerships and co-creation with customers nationwide while establishing an operating framework within the Furukawa Electric Group.