Multiaxis symmetrical drawing – A Mandala maker that doesn't suck

I’ve had a terrible time finding a good piece of software to draw mandalas with. To be honest, I don’t care what mandalas are but I’m obsessed with how cool it is to draw with replicated symmetry on multiple axis.

Without further ado, here it is (drag your mouse to draw):

I hope you find it addictive. Click to pop out.

So wow… just wow, this blew up. This little tool ended up making the front page of Reddit in one amazing thread in which  many people shared their mandalas. It was an amazing day in many ways, first of all I’ve never seen so many positive comments in a single thread online. The amount of people who seem to have been positively touched by this program is humbling. Drawing mandalas is apparently great stress relief for many and I’ve received several personal notes on how much this program had done for them. I did not see that coming to say the least. Then the fact that this tools was picked up by real artists pushed it to build creations I didn’t even know it was capable of. Lastly, my solar powered raspberry Pi handled hundred of thousands of connections in a single day which turned out to be a technical challenge on top of the overwhelming response. When I set out to create this program, I did not have the slightest idea that it would hit such a sweet spot. I mainly wanted to scratch an itch and couldn’t find any good apps out there. It is a true privilege to have had the chance so see so many people use a tool I made, and have them report they were positively touched by it.

Here is a few of the most amazing mandalas that were posted on the Reddit thread, this is what it looks like when real artists take over your tool 🙂


Nosy Monster

Robin & I have been working on a rover for the land since his toy RC car broke. I opened it up to see if I could fix it, and as with many things, I quickly came to the conclusion that “I’ll just throw a Pi in there and do it myself”.

Here’s the supposedly amphibian piece of shit that broke withing 1 hour of use.

Screen Shot 2016-10-16 at 6.04.40 PMThe engines still worked so I bought a Raspberry Pi Zero with a Pi cam, some super cheap Sunfounder Relays

From the ground up

Before anything else, we introduced the notion of a relay. In the past we used Lego motors and batteries to apply power directly to actuators and create little robots. I just snipped one of the wires and had Robin create contact manually so he could make the correlation between a closed circuit and the motor going.


With this “manual relay” in mind, we added a Pi controlled relay to make him realize that what the new gizmos do, is what he was doing by hand.IMG_7013


Ok we have a web controlled Lego motor going. Let’s see if we can replicate with the RC car’s motors.

IMG_7020IMG_7021First the manual relay


Then with the Pi controlled relaysIMG_7024nosy_monster_04Our first iteration looked like this and had a few issues. I separated the circuit powering the DC motors and each were powered by only 1 AA battery. I also had many adjustments to make in the logic.

IMG_7064Eventually, by adding a DROK voltage regulator, I was able to power everything from a single USB charger and prevent the motors from affecting the rest of the circuits.

IMG_7127But the extra hardware is hard to fit in the Nosy Monster so it’s unlikely that I will be able to fit the solar panel that would turn it into a completely autonomous robot. So I started googling for other potential frames and OH GOD I JUST STUMBLED INTO THE WORLD OF RC ROBOTICS. Oops…

In any case, I broke down the control into a step by step process. Instead of pressing “Go” and “Stop”, pressing “Go” will make it go for 1 second. There is 2 reasons for this. First, web based control introduces delays which make for a shitty live driving experience. Second, I would like this to behave like an actual rover on another planet. It reports back its sensors status and human decide on the next steps to follow. Heck I’m even thinking the next steps could be something that is voted on online. This would not be possible with “live” control.


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IPv6 link-local address to MAC address online converter

The converter

It can also be addressed directly via:
for all your API needs.


This converter was implemented per Dave Russell’s suggestion as a follow up to the MAC address to IPv6 link-local address online converter. If you are interested in the steps behind this conversion, they are simply a reverse of the original Mac->IPv6 converter.

Please note that of the various IPv6 notations, the one this script will expect is fe80::xxxx:xxxx:xxxx:xxxx.