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We designed and custom built a two part harness system to negotiate obstacles that the Trailrider could not. We used it for ladders, river crossing platforms, suspension bridges, and getting around fallen logs. The harness was simple, yet effective and served us well on the trip. In fact, the harness design was so successful that, after the trip, it won the 2006 Sam Sullivan Gizmo Award for being the invention that best defined the Tetra Society's mission statement of " assisting people with disabilities to achieve an independent and fulfilling life in the community". The Tetra Society is a non-profit organization dedicated to allowing those who are disabled to live an independent and fulfilling life by providing them assistance.
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How the Custom-Carrying Harness Worked
Brad wore a harness that was used in conjunction with another harness worn by a person to carry him in a piggyback fashion. Robert Green of Carleton Rescue Equipment and Roy Hamaguchi of the Tetra Society of North America contributed many hours of their time to designing the harness system. From his store, Robert donated the pieces that would become the harnesses and secured a donation of rope, pulleys, carabiners, and a gri-gri from Petzl America. Hobey Walker of Integrated Combat Equipment contributed |
his time and expertise to measure, fit and sew the harness system according to our design. There were many criteria that Brad's harness had to meet. First, people with quadriplegia have very delicate skin. This ruled out almost every style of harness on the market as they typically have leg and waist straps that apply a lot of pressure in a small area. This is not an issue for able bodied people, but for Brad, those straps would likely break his skin, which is a potential emergency scenario on the trail. We had to find a way to relieve that pressure. Also, Brad had to be sitting in this harness for hours at a time. That meant that every part of the harness that he was sitting on had to be extremely low profile. Any lump or twist underneath him could also cause skin problems. Finally, to get Brad in and out of it, the harness would have to open up entirely so Brad could be seated into it or lifted off of it. It had to be able to be done up or undone around him, rather than stepping into a harness like an able bodied person would.
For Brad's harness, we started with a pair of sailing shorts. The legs and waist of these shorts open up all the way and they have pads at the back of the thighs to protect a seated sailor from the gunwale of a sailing dinghy. Hobey sewed on a climbing waist harness and ran its leg loops directly under the short's thigh pads so that Brad's weight would be dispersed over the pad against the back of his leg. The sailing shorts have a full seat which dispersed Brad's weight over his whole bum helping relieve the pressure applied to his skin by the straps of the harness. Hobey then added webbing loops at Brad's waist, from which we would attach his harness to the carrier's harness. For lateral support, Brad also wore a chest harness. Tethers added to the chest harness brought Brad's shoulders tight against the carrier's back. Hobey sewed a long loop down Brad's back to contain and support his legs when he was suspended in the harness.
The carrier's harness required little modification. It was adapted from a work safety harness, having shoulder and leg straps, and a dorsal D ring belay point. Hobey added a weight bearing belt at upper chest height, with D ring attachment points under the carrier's arms where Brad's seat harness would connect. There were also connection points for the shoulder tethers to secure Brad's torso against the carrier.
Together, the harnesses had a belay point that started at Brad's waist and chest harnesses, and then ran through the carrier's dorsal D ring before attaching to the belay rope overhead. With Brad hanging in a piggyback position, we found it remarkably easy for someone to carry him. Without a problem, we could go up a sixty foot ladder or walk for about 200 meters at a time. The rest of the crew operated the belay system or ran packs and the Trailrider up ahead to where we would start rolling again.
Integral to our design was that the harnesses could separate. This meant that the carrier could put on his harness before connecting with Brad. But Brad's harness had to serve another function too. When we came to the Klanawa River, we had to use the cable car system in place to cross it. Hikers are meant to climb up a ladder to a platform where they pull the two person tram in along a steel cable, load it with two hikers and two packs before pulling themselves across. We did it slightly differently.
The carrier would walk Brad around to the far side of the elevated platform on the river's edge. From there, we dropped a line in between Brad and the carrier to pull Brad up to the platform. Suspended from the steel cable overhead, the line was attached to Brad's seat and chest harness on a 3 to 1 mechanical advantage system. We disengaged Brad's harness from the carrier's and pulled him straight up to the platform. We loaded him in the cable car, pulled him across and did the loading process in reverse, right down to re engaging with the carrier on the river's edge at the far side of the river.
The harness was destroyed in a fire two weeks before we set out on the trail. In those two weeks, we replaced a harness than had taken two years to assemble. Even after doing so, I believe that even with more resources, our design could only be improved with more time to spend perfecting the fit. As a prototype, it met all our criteria and it was extremely effective. We hope that other people will use it, or at least ideas from it in their own adventures.
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