While pursuing his MFA in Advanced Product Design at Sweden's Umeå Institute of Design, Jakob Kohnle did some "high-level" research. "[I] had the amazing opportunity to follow a pair of cell [tower] technicians very closely for an entire week," he writes, "during which they constructed a 72-meter (246-foot) tall 5G mast, working up in the mast as well as on the ground."
These folks need to carry tools up to the top, and safety regulations require the tools be tethered. But "there was a trade-off that had to be made," Kohnle observed. "With the current systems each tool requires its own tether, which means that more tools equals more ropes, and with that more clutter. Because of this, small to medium sized tools were often not tethered, even though these can still lead to serious injuries."
Kohnle then designed this clever TetherLock system:
Each tool has two sockets, one to secure it to the climber's belt or harness, the other to attach the tether. The sockets are designed so that inserting the mounting attachment in one socket automatically disengages the other, while holding the inserted member fast. Kohnle went above and beyond here, straying into Mechanical Engineer territory to work out the mechanism.
"This system enables a quick switch of a tool between the base and the tether, without it ever being unsecured."
It's a little difficult to understand by looking at images, but the video makes clear how the mechanism works:
"The Tether Lock has a simple and reliable construction. Additionally, the parts for the mechanism are the same between all tools making replacement and maintenance easy."
"The tether and the base can be attached to a harnesses or belt. The wrenches have the TetherLock integrated in the middle for optimal ergonomics and balance. Additionally the design is optimized for lower weight instead of strength to fit the needs of industrial climbers."