[CONTEST] Solar Powered Arduboy

Make an Arduboy that runs off of solar power and doesn’t use a battery!

I keep seeing this thing around the internet and I know we can do better:

I think the coolest implementation would be a PCB that is custom made with space for panels. But just gluing some panels to a working Arduboy would be ok, make it look nice with some 3d printed parts maybe.

It’s open ended.

No batteries! A super capacitor is ok, but it would be cooler if it was just able to run off of available sunlight.

Win an Arduboy Mini!

Bonus Level: Power an Arduboy with a crank also eligible for a prize.

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To get the power you need to run an Arduboy, it’s going to end up being an Arduboy glued to some panels (or one large panel)!

Oh good timing!

I try to use solar power for my original mobile game console.

I use super capacitor and solar panel. When I use 3.5F super capacitor, it runs for about 15min.

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Haha nice, those LED take a lot of current, have you measured?

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No I didn’t measure. But it is driven by PWM, so it is not so much current.

That’s why this gadgets front panel is smoke acrylic plate.

I was thinking a 3D printed case you can plop your arduboy in (with the back and battery removed)
and then just glue a solar panel onto the top of the flat pad.

I want to adjust the scad code to allow you to input the size of the solar panel, and it’ll change the size of the platform above and also add holes for wires and what not, so it’s nowhere near complete but it’s an alright proof of concept.

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I’ve always been interested in making a solar powered device with an eink/epaper display. It feels like the combination of being low power and readable in sun light would pair well with the solar panel.

Alas my hardware knowledge is too lacking to build one. Maybe some day!

An Arduboy with eink would not be too much fun with such a slow refresh rate though!

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No batteries? Lol, that’s retard. I don’t want to play in the sun :poop: also: no sun in Norway

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Solar calculators work indoors broseph

Bonus Level: Power an Arduboy with a crank also eligible for a prize.

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I’ve had one of these for over 30 years now… still kinda fun to play.

Compare the wattage that one of these calculators uses to what the Arduboy uses. Scale the size of the calculator solar cell up to match at see what you end up with.

I did a project where the microcontroller (SAMD51), radio (NRF24L01) with accelerometer (very low power) and mems microphone (ditto) were powered from a solar cell and a very bright LED floodlight. This was to bridge an air gap to allow movement.

Anyway, I looked at solar cells then and although we went with an IXYS model (only available from digikey AFAIK) I was disappointed with their performance when the illumination was pretty much anything less than full sunlight.

On a subsequent project I briefly tested flex solar cells from https://flexsolarcells.com/ and they did much better as a function of their spec in lower light levels (as in by a window in daylight but not full sun). May be worth a look for anyone keen to minimise their photovoltaic area.

Lastly, anyone who hasn’t used solar cells before should pay attention to the current/voltage curve on the cell, which usually shows the maximum power point. What these datasheets don’t show is that the current at which voltage drops drastically is variable, depending on illumination. For this reason, to get the best out of the cell you need to make sure that you don’t drag it into the condition of effectively open-circuit, pulling your voltage right down, even if you don’t implement maximum power point tracking. I have a solar powered night light in our bathroom which charges supercapacitors using an ATtiny402 that runs a charge pump to boost the peak voltage to 5.5V and a second ATtiny handles the PIR sensor, LDR and LED. A charge pump isn’t the most efficient way of using the solar power but it’s nice and simple. I had a fascinating chat with a guy in New Zealand who used to implement a battery charger from solar cells on agricultural electronics in the '90s using an inductor and the GPIO protection diodes on the PIC to charge the battery via the VCC connection to the PIC.

If I were going for this challenge, I think LCD display would be a good start for lower power and possibly a different chip or at least a slower clock rate.

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Which is probably what the device shown in the O.P. has.

Many “solar powered” calculators have fake dollar cells and an integral battery as their power consumption is so low and build is so cheap. There are some fun teardown videos online for them.

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And LCD is a better choice for play in direct sunlight, which makes sense for a solar powered device

Thinking about it, a good candidate for a 1000-year lifespan post-apocalypse game console would have the following qualities:

  • chunky Soviet-era-style build quality, built to last
  • similar low-power to existing Arduboy hardware
  • replaceable standard-sized batteries, easy to source
  • regulated input to cope with dubious-quality power sources - alkaline, NiMH, NiCad, lithium etc.

i.e. pretty much the Keystudio knock-off :slight_smile:

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128x64 LCD,

Datasheet says max 3.0mA draw without backlight, guessing maybe 2mA average draw, suer low.

Being LCD, the refresh rate might be a problem though of course, as with the original Game Boy

The black on yellow/green version would be a better choice. It’s more transreflective, meaning it will be easier to read in bright light without needing the backlight.

If you were really going for power savings, use something like this: