Project Description:
Our goal was to create a device that could provide substantial and reliable power for hikers and campers. Our design is centered around solar panels, which provide a mostly consistent and passive way of collecting energy and turning it into electricity. Our device consists of three subsystems; the solar panel assembly, the telescoping base, and the electronic components. These are all housed in an approximately 100 x 200 x 50 mm rectangular volume. Energy tranfer is managed using an MPPT solar power manager, stored in a LiPo 18650 battery pack, and output through USB ports.
The electronics that manage battery charging/output include three 18650 LiPo batteries, six solar panels, and the MPPT solar power manager. The MPPT solar power manager keeps a constant current and voltage. This is unlike PWM charge controllers that only manage the voltage, and lead to significant power loss. This is ideal for our application because even in inconsistent lighting the MPPT charger will output 5V and 1 amp which is key for battery health and safety.
The solar panel assembly contains 6 solar panels, two small and four large, housed in custom cases. These panels are wired in parallel to maintain a 5V output. The two small panels fold out from the small sides of the device to be flush with the top of the device. The four large panels are arranged in pairs, one folded under the other, so that the pairs fold out from the long sides of the device, then the bottom panels fold out again to expose all four panels.
The electronics are housed in the center stack of the device, which also acts as the telescoping base to keep the solar generator, when deployed, above uneven ground, or out of the user’s way if mounted to a backpack. The batteries, BMS board, and Arduino are mounted here. The USB ports used for charging devices are located on the BMS board in the center stack.
