A Multi-Tasking Wonder Worker, Crane Helps To Erect Buildings, Create Roads

HAMPTON, Va. — A new type of crane can assemble itself, lift loads, hop onto a mobile platform to head to a different worksite, perform grading and site-preparation jobs, and more, all by remote control.

Oh, by the way, it will do all this on the moon. And if need be, crane operators could be on the Earth.

NASA experts at the Langley Research Center briefed the media on the Lunar Surface Manipulation System (LSMS), and then demonstrated a full-scale model of the device.

The experts included Diane Hope, program element manager in the LSMS program, and John T. Dorsey, senior research engineer with the Structural Mechanics and Concepts Branch at NASA Langley.

Designed, developed and built by Langley researchers, the crane on a voyage to the moon will be an unprepossessing, roughly yard-high set of super-strong but very lightweight, inter-nesting beams. Some cables and electric motors complete the straightforward package.

But upon arriving on the moon aboard the Altair Lunar Lander, the crane will spring to life, unfolding itself from a lump of structural pieces to form a working crane.

Its cables resist pulling and its strong members resist pushing or compressing forces, making it strong in multiple ways.

Once erect and deployed as a recognizable crane, it can lower a moon buggy, a six-wheeled vehicle, to the lunar surface. Then the crane can attach itself to the buggy (like an inchworm, it can attach itself at either end to a base) and go mobile, lowering an earth-moving scoop to the surface that then is attached to the buggy. At that point, the crane is set to act as a bulldozer/power shovel for site preparation, roads construction, building landing pads and more.

Then the LSMS crane moves back to the lander and unloads items onto the prepared site, such as a large lander airlock module, or a lunar oxygen generation plant.

(Since the moon has little atmosphere, where would that oxygen be found? In the lunar soil, or regolith. The oxygen in the soil is combined with other materials, so there would have to be a process to separate the oxygen into usable pure form, which is the job of the oxygen generation plant. Then, that oxygen plus whatever Altair brings with it from Earth could be purified and reused thanks to the same system that provides breatheable oxygen on Earth: plants that would be grown on the moon.)

The LSMS with that dirt scoop also would be able to cover the habitat and work modules with lunar soil, to shield astronauts inside from harmful space radiation.

Understand, Altair wouldn’t be a tiny vehicle. So the crane has to be huge, able to reach as high as the top of a house, or 30 feet up (it can have a 40-foot reach with an extension) and as much as 25 feet out.

And the crane is strong. On the side of one structural member is a picture of Earth, the big blue marble, and a notation that the maximum load that can be lifted on the home planet is 150 kilograms, or 330.7 pounds. Then there is a picture of Mars, the red planet, where the gravitational pull is much weaker. There, LSMS can heft something that would weigh 500 kilograms, or 1,102 pounds, on Earth. Finally, there is a picture of the moon, where the LSMS can hoist an object that would weigh 1,000 kilograms, or 2,205 Earth pounds (more than a ton).

As a rule of thumb, something on the moon weighs one-sixth what it would on Earth. Something on Mars weighs a third as much.

Depending on configuration and where on the crane the load is suspended (the elbow instead of the wrist), it can lift up to 3,000 kilograms, or 6,600 pounds.

For all the myriad functions it provides, and the strength and lifting power it affords, one might expect a highly complex system. And one would be wrong.

The crane has a single vertical member called a kingpost. It is attached to a base, or to a lunar buggy, at the waist, so called because it can swing back and forth on its axis, much as a person can turn at the waist to face in different directions without moving the legs or feet.

Then there is the shoulder, a point at the top of the kingpost where the horizontal member attaches. That horizontal member is the arm. At the end of the arm is the elbow, followed by a second horizontal member called the forearm, which ends at the wrist.

In a demonstration in a hangar-sized building at NASA Langley Research, an operator sitting at a computer ran the crane through its paces. He was aided by cameras mounted on the LSMS crane, and on a nearby wall to give him a lateral view, because this work isn’t as easy as it would appear. Video from the cameras was displayed on a computer screen next to the operator. When the real LSMS crane is built and boards the Altair lander for the trip to the moon, it may have cameras on arms that would splay outward from the shoulder joint to give the operator that sideways view of objects being lifted.

Objects used in the demonstration were sitting, waiting, on a raised platform, with each object having atop it a metal lifting hook.

Unerringly, the operator would swing the crane to the object to be lifted, selecting first one that was in a remote spot on the platform and difficult to reach. A horizontal rod at the end of the hoist component at the end of the crane would grab the hook on top of the object and the crane would lift the object off the platform and lower it to the floor. Then the operator reversed the process and picked up each item and placed it back on the platform.

It’s a highly capable system. Still, it’s not yet complete.

The NASA Constellation Program now is developing the Orion space capsule that will carry Altair and a crew to the moon (Lockheed Martin Corp. [LMT]), boosted by the Ares rocket that will have various components (The Boeing Co. [BA], Alliant Techsystems Inc. [ATK], and Pratt & Whitney Rocketdyne, a unit of United Technologies Corp. [UTX]).

For lighter loads, the crane could be fashioned to handle small cargo packages, delicate science instruments, inspection devices for peering into hard-to-access locations and unpressurized rovers.

In a more muscular configuration, the LSMS crane could handle large cargo packages, habitat modules, power supply modules and regolith processing equipment.

Either way, it offers light weight (while the demo model used aluminum, the real deal going to the moon will be made of sophisticated composite materials), a simple design that’s easy to maintain, repair and upgrade, with a long life, operational simplicity, and cost savings because it is modular, expandable and upgradeable.

LSMS in June proved it can deliver as promised, in tests at the lunar-like landscape of Moses Lake, Wash.

The crane hoisted various modules without any strain, and withstood something it won’t have to contend with on the moon: buffeting wind, and even some occasional rain.

This crane or something similar operating on the same principles could be just as serviceable on Mars, though that mission may not occur until 2030.