A blasting test of a new system for remotely loading explosives for tunnel construction, developed by Associate Professor Takahiro Nozaki of the Faculty of Science and Technology, Keio University, and general contractor Obayashi Corporation, was conducted at the construction site of the San-En-Minami-Shindo No. 6 Tunnel in Nagano Prefecture, and successfully detonated explosives on the excavation face of a mountain tunnel. It is expected to be the first step towards unmanned tunnel excavation work.
According to Keio University, the blasting test was a success, with a loading robot mounted on a large heavy machine being operated from outside the tunnel, 30 meters and 320 meters from the blasting site, to load explosives and detonate the explosives. Using a technology that remotely reproduces haptic sensations (Real Haptics®), a worker in an operator's room outside the tunnel remotely loaded the explosives while visually checking the area around the explosive hole on a monitor.
According to Keio University, Real Haptics® is a technology that transmits contact information with real objects and the surrounding environment in both directions to reproduce the sense of touch. By transmitting the sense of touch that humans feel when touching an object, such as hardness or softness, the elasticity of a balloon, and autonomous movement, it is possible to reproduce the same sense of touch at the hand of a remote operator.
As part of NEDO's "Public and Private Sector Support Project to Discover Young Researchers," Associate Professor Nozaki's research group and Obayashi Corporation applied Real Haptics® to develop an automatic explosives loading system in September 2023. In indoor testing, they succeeded in automatic loading using remote loading technology and the haptic data transmitted by the remote loading technology.
Serious accidents in mountain tunnels frequently occur during the installation of steel supports and during the loading and wiring of explosives. Installation of supports using heavy machinery has already been remotely controlled and automated, but loading and wiring of explosives requires delicate force and dexterity, so it is still done by hand while taking safety measures.
Associate Professor Nozaki and Obayashi Corporation are working to integrate the automatic operation of large heavy machinery with the automatic explosives loading system, as well as automating the task of tying the leg wires to detonate detonators, with the aim of utilizing this series of technologies at mountain tunnel construction sites.
