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.

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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

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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

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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.

 

Cool Duplo Project #38 – The Tallest Duplo Tower in the World – Reaching for new heights!

For the occasion of the First Lego League competition at the Thayer School of Engineering at Dartmouth, I decided to beat my previous record for the highest Duplo tower in the World.

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.

Deploying safety netting, we’re as much worried about one of the many kids attending the First Lego League knocking the tower down as we are about the tower crashing on the crowd.baea98da931cda1d-blob

Your shipment of Duplos has arrivedIMG_7262

Peter and the ready-to-assemble towerIMG_7265

Here is it in all of it glory, all 1082 pieces of itIMG_3502IMG_3507IMG_3528

Here is how it met its demisedemise

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 😀