Off-world Power Generation Lab 1: Free Space 1W Transmission

NEEDED: POTENTIOMETER(S) (variable resistance) to adjust power to laser

Overview

• Use a full-sized solar panel to power a large battery through a commercial regulator.
• Use the large battery to power a raspberry pi.
• Use the large battery to power a small laser through a voltage regulator that reports the delivered power.
• Add an on/off switch to the laser circuit that is controlled by the pi.
• Point the laser at a diffraction lens that illuminates a small solar panel.
• Use the small solar panel to power a small battery through a voltage regulator that reports the delivered power.
• Use the small battery to power...
  • something simple, a fan or a light, through a usb multimonitor
  • an arduino that can monitor the voltage and current
  • a lan-connected raspberry pi that can monitor the energy and call an API to report snapshot values. These guys suggest that the best way is via an arduino, really?

Remember: we regulate the voltage, everywhere. Only voltage can force current where it is not wanted.

Can we keep the arduino powered 24/7?

[large panel] > [regulator] > [battery] > [pi]                    SPACE
                                        > [regulator] > [laser]   =====>   [small panel] > [regulator] > [battery] > [arduino]

Gear

Primary

• 100W solar panel
• solar power regulator - I have no idea if this will do the job yet... but it's on the way!
• 88 Wh battery
• fully-configured raspberry pi 3, hostname Lime
• $45 300mW laser
• small solar panel
• 15 Wh battery
• Arduino Uno

Secondary

• lots of experimental voltage regulators, what works is still TBD
• Breadboards
• Multimeters (two hand-held, two usb inline)
• 190-540nm laser goggles for our 405nm laser
• Winners® 7A DC 60V Adjustable Step Down Regulator
• LM317 on a board with a dial
• a bag of LM317T Adjustable Regulators really popular, need heatsinks!
• Ultra Low Voltage Boost Converter i looked hard for a very-low-voltage booster, will this work? the 5V booster of projects i found is no longer avail
• Arduino Compatible Expansion Board
• a full power supply kit, probably good to build-and-learn, and also probably very useful

More

• cheap <$1 5mW laser
• fully-configured raspberry pi 3, hostname Carambola
• bare Arduino Uno

Connectors

• large panel uses MC4 connectors: we got a bunch of connectors to splice wire into
• commercial solar regulator: raw wire input/output
  • Output: 12V Battery (make sure to config to use 12V not 24V)
  • Input: Max solar Panel Power: 360W
• large battery
  • some sad Japan Jack Input: 14-25V, 3A
  • USB Output: 5V/2A USB (12V/6A, 16V/5A, 19V/4.5A, 24V 3.5A??) - USB QC: 5V/3A, 3.6V-12V, 18W Max.?) wtf
• laser power: raw wires - replace power supply with an inline resistor??
• small battery uses USB out, microusb in: we got a bunch of usb connectors and cables
  • Output: 5V/1A USB
  • Input: 5-6V/1A MicroUSB

TODO

• make the pi sleep
  • use an arduino! uugear explanation
  • if arduino is a pita, use witty pi 2 or witty pi mini board with pi, it runs its own clock, can turn raspberry pi on/off, can pulse battery supply to keep it alive, should make a sleeping pi arrangement SO MUCH easier [1] mini pinout
• all the regulators
• more breadboards, perfboards, any needed soldering thingees
• pi uses some adapter bullshit
• arduino is also a pita
• consider this sparkfun boost converter, handles low power