An interesting development - something that could be hacked and built in someone's garage. From the Australian Defence Science and Technology Group:
FLEXIBLE SKELETON TAKES THE WEIGHT OFF
The current generation of powered exoskeletons uses a complex system of rigid linkages and mechatronics. They are showing real promise in enabling the wearer to lift and move about with very heavy loads.
However, the design and natural movement of the human body tends to battle with the exoskeleton movement, causing a dramatic increase in the user’s energy cost when walking with a load. These systems tend to be heavy (>35 kg), very expensive and power hungry.
Defence science and technology researchers have developed a simple, lightweight (3 kg) fully-passive exoskeleton. This system uses Bowden cables to attached to a rigid backpack frame. The cables run down the back and legs to the base of the boot and transfer approximately two thirds of the backpack load to the ground. This load force bypasses the user’s body, reducing compression forces from the backpack load through the torso and legs.
The benefits of such a system compared to a powered exoskeleton include: simplicity, no requirements for heavy batteries; low cost; easier to integrate with the user and equipment and redundancy when no longer required – remove and add to pack.
The development is at a proof-of-concept stage with early testing showing encouraging results. However, the biomechanics of the system require extensive refinement to ensure it is integrated optimally with the soldier and truly fit for purpose.
Bowden cables are a wire rope encased in a flexible semi-rigid tube. These allow both pushing and pulling forces to be transmitted around a variable path. One common use is for small engine control - motorcycle and lawnmower throttles, etc... Very clever.
