Soldiers gotta eat.

That means that when the front line moves, kitchen equipment moves too, including great big refrigerators that typically measure 20 feet long, 8 feet high and 8 feet wide. That’s a logistical headache.

What the Army really needs is a foldable fridge, something maybe one-third the size of the typical container than can be easily opened up to become a full-sized cooling unit. Fortunately, the Army’s Natick Soldier Research, Development and Engineering Center’s Combat Feeding Directorate says it has prototyped just such a thing.

“There are tens of thousands of refrigerated container systems in use in the military. They may not be on the move in a daily basis but thousands may get shipped to a war zone in the course of a conflict. It’s an essential part of any larger-scale deployment,” said Ben Williams, mechanical engineer and product officer. “You need it for food, you need it to make ice, you need it for morgues.”

Williams’s team recently announced the successful prototyping of a collapsible system that’s not only smaller and easier to transport but also more fuel-efficient. The collapsible fridge can run on 75 percent less fuel thanks to a smaller motor and high-efficiency insulation.

Developing a folding fridge was “easier said than done,” Williams said.

First, the team had to sort out a method for creating airtight seams. “When it expands, you need to seal the walls in a way that doesn’t allow a lot of heat in, so that the system can perform as required,” he said.

There were also issues around engineering and materials. “It has to have some durability, things have to line up appropriately. And the panels have to be light enough that a person can physically manipulate them in order to set up the container,” Williams said. “You have to be clever about how the walls collapse, to make it all fit together.”

Most of these issues got resolved through the use of composite materials that incorporate vacuum-insulated panels. They’re light and thin, compared to standard foam insultation, so they can be handled easily while still delivering high performance.

Layered on top is a proprietary thermal management coating, a technology that helps deflect heat off the surface of the unit, reducing absorbed radiation by up to six times. “These containers are kept outside, they get a lot of sunlight, so reducing the infrared can make a big difference to their performance,” Williams said.

He expects it will take three more years of development and testing to produce a field-ready product. When it’s done, though, the collapsible fridge could go a long way toward easing a longstanding logistical burden facing all the armed services.

Autonomous delivery

In other logistics news, the Office of Naval Research announced recently that it had carried out a successful helicopter flight demonstration in its Autonomous Aerial Cargo/Utility System (AACUS) program.

A partnership between ONR and technology company Aurora Flight Sciences, AACUS uses sensors and software to improve logistics by helping manned or unmanned helicopters to detect and avoid obstacles such as telephone wires; to fly in bad weather; and even to carry out logistics missions autonomously.

“Imagine a Marine Corps unit deployed in a remote location, in rough terrain, needing ammunition, water, batteries or even blood,” Walter Jones, ONR’s executive director, said in a news release announcing the demonstration. “With AACUS, an unmanned helicopter takes the supplies from the base, picks out the optimal route and best landing site closest to the warfighters, lands, and returns to base once the resupply is complete — all with the single touch of a handheld tablet.”

Planners say an operator with minimal training can use the system to easily call up supplies. During the recent UH-1 “Huey” demonstration, a Marine with no prior experience trained for just 15 minutes before successfully putting the system through its paces, delivering supplies and even autonomously selecting an alternative landing site based on last-minute no-fly-zone information.

“We’ve developed this great capability ahead of requirements and it’s up to us to determine how to use it,” said Lt. Gen. Robert Walsh, commanding general, Marine Corps Combat Development Command, in a news release. “The young Marines today have grown up in a tech-savvy society, which is an advantage. We’ve got to keep pushing and moving this technology forward.”