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.
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.
Ok we have a web controlled Lego motor going. Let’s see if we can replicate with the RC car’s motors.
Then with the Pi controlled relaysOur 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.
Eventually, 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.
But 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.
With an awesome venue and a lot of eyeballs on the project, it was time to do something big… Except that I barely went over my previous 17 feet. I thought I had much better chances with an improved design but I only made it to 20.5 feet. In part because I was risk averse given the project had visibility. But also because my design didn’t deliver what I thought it would in terms of resistance to wobbliness. I’ve learned a few lessons and will bring a laser level to my next attempt.
And a timelapse of its build
Thank you to the wife & kiddo, Jared, Oliver, Dan, Crystal, Peter, Sarie & the Thayer School of Engineering for all the help in making this possible 😀
With a hand pump being our only access to water, we’re taking extra precautions to ensure it will survive the tough winters we get. While technically not necessary for the pump we got, it can only help and should also improve the chore of gathering water. And we get a greenhouse out of it
I like the idea of combining under one roof, 2 functions where freezing is non-desirable, water and growing plants. Our dream is to build a bigger greenhouse down the road and maybe even heat it. Water for the plants would be right where it’s needed and benefit from the higher temperatures. Our only worry right now is whether it will survive the freak wind gusts we get.
Our well is somewhat unique in that water has been oozing off the top constantly at a rate of about 2 gallons per hour. This is a problem in the cold months as it can freeze and damage the casing or the hand pump. Since we had the well drilled last March, we knew we’d have to take care of this before Winter came back. Well, here we are; I spent the whole Summer thinking about what we could do with it. The standard solution in these cases is to create a sump pit near the well to dispose of the water and give it back to the ground bellow frost line. But few things are standard in our house, so I thought about maybe pumping the water out with a Raspberry Pi driven pump but this presented its own set of challenges.
Finally, I decided to indeed dispose of the water in the ground but first run it all around the house, 170 feet away from the well. It brings me to great soil which percolates well; above all, it gives us a fresh potable water line running all around the house which we can tap for projects.
We could circulate it in a coil for air conditioning in the house, we could use it for filling our outside shower in the Summer without having to move water, we could have it keep an animal water tank replenished. In other words, the flowing water becomes an opportunity for improvements as opposed to something we just dump back into the ground.
Of course, it’s harder, less standard and more costly. The well is by far the most expensive project we’ve undertaken so far, we have spent on it as much as than the house itself.
Ken is back for a huge trench
This Summer having been very dry, the well actually stopped flowing a few weeks ago. It’s unlikely that the water tables will fill up very much before Winter is here for good, so the project will not be tried by fire immediately. We expect trial when the snow melts next March. Maybe our well was relieving pressure and will never flow over the top again which would suck given everything we’ve done for it. No matter what, we’ll be ready if it happens, and counting on it for projects if it does so consistently.
6′ down the well casing, Mike helped me tap a threaded 3/8″ hole so the extra water would go in the black pipe underground. This is the poor man’s way of doing it without a pitless adapter, down the road when we are ready to run water to the house we will make that hole bigger and do it right with a pitless adapter. It didn’t make sense for me do “do it right” immediately because installing a pitless means having to remove the hand pump, which means I might as well put in a second pitless for running water to the house. Which means I might as well dig another trench to the house. Et cetera… It’s just to much to tackle for now, and we don’t even have room in the house for a water tank.
Except that of course, all the rain that we didn’t get this Summer decided to come down right before we had to work in the hole, it made it hard to work in, and it brought the water table up. For the longest time I thought that what we had rigged together was leaking which could contaminate the well. I ended up redoing it all and checked it thoroughly to be convinced that no water from the ground would find its way to the well. I spent many hours after dark in a muddy hole re-doing and checking until I was certain no water was seeping out.
Take 2, with a check-valve, currently checking for leakage
All in all this was a long, stressful and costly project. As with many things, I’ve learned a whole lot in the process and I feel more prepared for the next challenge. The hope is that it will also be worth it to have this fresh water flowing around the house that we can tap into for projects. I said earlier that the well had stopped flowing at the top. Well 6′ down the casing, we found out it hasn’t It was a good surprise to find water there.
It’s very nice to be able to rely on Mike, Matt & Rick for help & feedback on this massive project. Once again we find ourselves indebted to people’s kindness in helping us.
I will add hay to the top of the leach field for good measure in ensuring it doesn’t freeze; the setup will then be tested by this coming Winter.