Power Backpack for Energy Harvesting and Reduced Load Impact

Long-distance
walking with heavy loads is often needed when going
hiking or for field rescue, which is prone to cumulative fatigue.
There is also a great need for labor-saving and biomechanical energy
harvesting in daily life for extended security and communication needs.
Here, we report a load-suspended backpack for harvesting the wasted
energy of human motion based on a triboelectric nanogenerator (TENG).
Two elastomers are incorporated into the backpack to decouple the
synchronous movement of the load and the human body, which results
in little or no extra accelerative force. With such a design, through
theoretical analysis and field experiments, the backpack can realize
a reduction of 28.75 % in the vertical oscillation of the load and
21.08 % in the vertical force on the wearer, respectively. Meanwhile,
the mechanical-to-electric energy conversion efficiency is modeled
and calculated to be 14.02 % under normal walking conditions. The
designed backpack has the merits of labor-saving and shock absorption
as well as electricity generation, which has the promising potential
to be a power source for small-scale wearable and portable electronics,
GPS systems, and other self-powered health care sensors.