Good Thinking

A winning idea for wall-climbing

A winning idea for wall-climbing
Two climbers ascend a silo, using Utah State University's PVAC system (Photo: USU)
Two climbers ascend a silo, using Utah State University's PVAC system (Photo: USU)
View 5 Images
The Utah State University team, suiting up one of the Air Force-supplied climbers (Photo: USU)
1/5
The Utah State University team, suiting up one of the Air Force-supplied climbers (Photo: USU)
The PVAC climbers nearing the top of the silo (Photo: USU)
2/5
The PVAC climbers nearing the top of the silo (Photo: USU)
One of the PVAC climbers setting out (Photo: USU)
3/5
One of the PVAC climbers setting out (Photo: USU)
The victorious Utah State University team (Photo: USU)
4/5
The victorious Utah State University team (Photo: USU)
Two climbers ascend a silo, using Utah State University's PVAC system (Photo: USU)
5/5
Two climbers ascend a silo, using Utah State University's PVAC system (Photo: USU)
View gallery - 5 images

Last month we told you about a team of Brigham Young University engineering students, who created a clever Batman-inspired wall-climbing system. They were competing in the U.S. Air Force Research Laboratory’s 2012 Service Academy and University Engineering Challenge, in which teams had to design gadgets that would allow soldiers to safely and quickly ascend vertical surfaces. Given that the Brigham Young entry didn’t take first place, however, we thought it only made sense to take a look at the entry that did ... and that would be a little something known as the Personal Vacuum Assisted Climber (PVAC), designed by a team from Utah State University.

The contest took place April 16th to 20th, at Wright State University’s Calamityville tactical laboratory in Fairborn, Ohio. It was required that all competing devices must allow users to climb higher, faster and with less effort than current techniques allow. The devices also had to be reusable, permit multiple pitches within one climb, allow the operator to keep one hand free for using other equipment, and be capable of getting three people each carrying 300-pound (136 kg) loads up a 90-foot (27.5-meter) vertical silo within 20 minutes.

At the heart of the two PVAC units were two back-mounted carpet extractor motors. These each created suction with a three-stage impeller, were powered by seven lithium-polymer batteries, and created a seal against the wall using connected handheld pads lined with closed-cell foam. A pressure release lever on each pad allowed it to be secured against the wall when being used by the climber to pull themselves up, then released so it could be lifted higher.

A gauge indicated safe vacuum levels, while a volt meter let climbers know if they were about to run out of juice (as it turned out, they just made it).

Hanging beneath each pad was a stirrup, with a foot rest made from fiberglass rebar. Users placed one foot in each stirrup, then set to climbing the wall. “The motion of the system is like that of climbing a ladder,” team leader TJ Morton told us. “The only difference is the climber must learn to correctly distribute his weight as he climbs.”

The Utah State University team, suiting up one of the Air Force-supplied climbers (Photo: USU)
The Utah State University team, suiting up one of the Air Force-supplied climbers (Photo: USU)

Two PVAC-equipped climbers scaled the Calamityville silo, trailing climbing rope behind them as they went. When they reached the top, they secured the end of this rope to the wall face using a “glue pad” – this consisted of fiberglass mesh with a nylon rope-attachment strap sewn into it, and very fast drying, high strength superglue. Once that patch was secure, two other climbers (still waiting below) attached ascending devices to the ropes, then winched themselves up to join their colleagues at the top.

Although the contest didn’t require it, the PVAC system also allowed climbers to get up around a protruding ledge at the top of the silo. This was accomplished with the addition of rope-style rock-climbing ladders and “daisy chain” climbing straps, that could be attached to the pads when needed.

“We feel that we were successful in completing the challenge because of the extensive testing we did prior to the competition,” said TJ. “There were many impressive designs and ideas displayed, but very few had the success they had hoped for. We feel that we did a fair amount of testing and we still had a few hiccups at the competition. So, the biggest lesson we took away from this is that testing leads to success and that you can never test too much.”

Source: Wright-Patterson Air Force Base

View gallery - 5 images
9 comments
9 comments
Ct
The element of surprise from climbing a vertical wall is lost from the sounds of two whirling motors.
Slowburn
I am not convinced that a tiny ICE would have added enough noise to matter and it would increase use time by weight.
domshmom
Got to say though, this has already been done - by the BBC science programme Bang Goes The Theory - http://www.youtube.com/watch?v=W1qoINo2MPM
Joe Sobotka
I'm guessing this won't work on rocky/uneven surfaces. Also how much does the pack weigh. And if you have that strapped to your back what about the gear you need for your mission? Although I suppose that can be winched up once you're at your destination
Artisteroi Rlsh Gadgeteer
A middle school kid built the same thing 3 years ago. I hope these "winners" are going to give credit to him.
http://youtu.be/i31AYw8uCyY
Alyssa Wahlin
Actually, the system has been designed to climb up structures with some uneven surfaces including brick. This is the main difference between our design and previous, similar ones.
Aquatus1
Chances are pretty low that this type of gear is going to be used for cliff climbing. It was designed for soldiers, and soldiers generally try to find ways around having to stay on an open, exposed, unstable surface (like a cliff face), for extended periods of time. This sort of device would work very well in a more urban or industrial environment. In many situations, like work offices or oil rigs, there is less chance of being seen on the back side of a building than in the stairwell. Similarly, it is more likely that the sounds be mistaken as regular machinery, or masked altogether by the ambient sounds.
VHomer
I built three climbers on a DARPA contract about 10 years ago. They were powered by batteries, an air turbine, or a weedeater engine. The weedeater engine one was the fastest and would lift over 500 lbs with an all-up weight for the unit of around 20 lbs. The battery powered one weighed 17 lbs and would haul 200 lbs up over 300 feet of rope. They worked on rope sizes from 1/8" Spectra to 5/8 climbing rope. The company I worked for left town and eventually patented and marketed the battery powered version. Unforrtuanetly, when they filed the patents they failed to remember that I designed and built the prototypes. Don'tcha just love the patent system?
David Cannon
@VHomer, I'd recommend consulting an attorney. We haven't converted into a "First to File" patent system yet, and depending on what kind of Proprietary Information Agreements you signed, you may be able to dispute the patent. There is no statute of limitations on patent infringement.