Powered rope ascender
February 19, 2007 - A motorized pulley, which will let military, paramedics and firefighters climb up 30-storey buildings in 30 seconds, has become a reality thanks to the Powered Rope Ascender. Developed initially for military use, the Ascender is now being touted as a valuable device for the emergency services. The Ascender has been awarded the Lemelson-MIT Student prize for U.S. inventions.
Imagine a device that allows you to soar up a rope, scaling the highest cliffs and tallest buildings at breakneck speeds like some comic book hero. Such a device has become a reality thanks to the Powered Rope Ascender. Developed initially for military use in urban warfare situations, the Ascender is now being touted as a valuable device for use by the emergency services in rescue operations.
The Ascender was first developed for the 2004 student U.S. Army Soldier Design Competition. Following a requirement to create a lightweight device capable of rapidly lifting a fully equipped soldier up a rope, principal inventor Nathan Ball and three other students at the Massachusetts Institute of Technology came up with a prototype cobbled together from old power tool parts. Ball is now the Chief Technical Officer of Atlas Devices, a company set up after the competition to exploit the commercial potential of the gadget. He was at the forefront of developing the novel split capstan, the key to the Ascender’s efficient operation. This consists of a series of rollers sitting on a turning spindle that pulls the rope tighter as it is wound around the rollers during an ascent.
Atlas Devices claims that speeds of 10 feet (3 metres) per second are possible, with a fully loaded fire fighter or soldier able to reach the top of a four-story building in less than four seconds. This is about the speed of a typical elevator, and much quicker than plodding up a staircase with heavy equipment or using a traditional winch. Furthermore, ascending only requires one hand, leaving the other hand free to carry equipment. However, the rope does need to be attached at rooftop level before any ascent is possible. So unless a rope is left permanently in position on a building, it would only be of use to a second batch of rescuers.
Remote operation is possible, allowing equipment and supplies to be hauled up or down a rope. And by combining the device with a suitable gearbox and an appropriate rope, it will provide an effective winch to tow loads of more than 1,000 pounds (454 kilograms) – very handy for moving vehicles or other obstacles blocking roadways. As it is powerful enough to pull a rescuer and casualty up a rope together, it is particularly useful in recovery operations. Weighing just 15 pounds (7 kilograms), the Ascender can be easily carried to remote mountainous areas.
Users have two options for powering the device. They can either rely on the integrated rechargeable lithium-ion battery, which allows it to lift a 250-pound (113-kilogram) load over 600 feet (183 metres) on a single charge, or power from a vehicle through a special adaptor. Atlas Devices has recently succeeded in securing its first contract, worth US$120,000, from the U.S. Army to provide various prototypes. But the Company expects the cost of the Ascender to come down significantly in the next few years when it might even be within the budget of the average weekend adventurer.