Hikers contemplating tackling some of the most daunting treks in Japan - such as the 1,200-kilometre (750-mile) pilgrimage that visits 88 temples on Japan's Shikoku island - should soon be able to get a leg-up with the help of a robotic exoskeleton that optimises a walker's gait.
The Tokyo Institute of Technology is collaborating with Tokyo-based tech venture Walk-Mate Lab and Japanese airline All Nippon Airways to explore the concept of a "new walking journey" that brings together ancient pilgrimages and modern robotics technology.
The companies have been testing their Walk-Mate robotic suit, an external skeleton that is strapped over the user's clothing and comes equipped with sensors at the waist and ankles and a battery pack.
Originally designed to help people walk again who have suffered a stroke or have Parkinson's, or another debilitating disease, the equipment synchronises and optimises the user's steps and the rhythmic swinging of their arms.
While other robotic exoskeletons detect electrical impulses from muscles and then use the motors in the suit to mimic and enhance the actions of those muscles, the Walk-Mate uses the rhythm of walking to stabilise the user's steps and get them into a settled and comfortable routine.
According to the researchers, the user's walking speed and stride length both increase when wearing the suit. Extended use of the unit imprinted those same walking habits on the user.
The device goes beyond the physical, however, with participants in a number of tests reporting that they felt a "sense of togetherness" when using the equipment, both with other walkers and the robotic suit they were wearing.
Walk-Mate was put through its paces most recently in mid-October, at Mount Koya, a holy peak in Wakayama Prefecture that is home to the Danjo Garan temple complex and the mausoleum of ninth-century monk Kobo Daishi, also known as Kukai, the founder of Shingon Buddhism.
The real test of the units' mettle, however, was on a stretch of the Shikoku 88 Temple Pilgrimage, with the designers suggesting that the Walk-Mate was replicating the gait and pace of Kobo Daishi on the route.
The pilgrimage is one of the few circular holy hikes in the world, taking in 88 temples and locations where Kobo Daishi trained or meditated in the ninth century.
Today, pilgrims typically wear the white hakui vest, which represents purity and innocence (although, in the past, it also indicated the death shroud, meaning that the pilgrim was prepared to die at any point on their journey), and the sugegasa conical hat.
Hikers may also carry a rosary, a small bell to ring after reciting each sutra, and a zudabukuro cloth bag in which to carry candles, incense and a pilgrim's book, which is stamped after praying at each site.
Another critical item is the kongozue staff, which is believed to be the embodiment of Kobo Daishi as he guided pilgrims, but also served as a grave marker in centuries gone by for those who died on the arduous 1,200km route.
The temple of Ryozenji, in Tokushima Prefecture, is considered the traditional starting place for the journey, which takes around six weeks to complete for someone who can cover 30km a day.
For the less energetic - or those not equipped with a Walk-Mate - visiting every location on the trek by car would take around 10 days.
The developers of Walk-Mate say they aim to create a "new style" of travel, which they refer to as "Pilgrimage x Robot", and encourage the revitalisation of rural parts of Japan through tourism.
