This week on Maker Update, a robot that flings paint, an RC duck, a pocket-sized replicant detector, and a pumpkin for your Pi.

++Show Notes [Maker Update Ep. 252]++

-=Project of the Week=-

Flingbot by JBV Creative
https://jbvcreative.com/blogs/project-details/the-flingbot

-=More Projects=-

Dave – the Remote Control Duck By Jude Pullen
https://www.instructables.com/Dave-the-Remove-Control-Duck/

Pocket-Sized Voight-Kampff by James Brown
https://twitter.com/ancient_james/status/1441558262604713988?s=03

Pumpkin Pi by Caleb Lemoine
https://github.com/circa10a/pumpkin-pi

-=Tips & Tools=-

Browser-Based SVG Nesting Tool
https://github.com/Jack000/SVGnest

Deep Dive into SPI by Jim Heaney
https://hackaday.com/2021/09/16/taking-a-deep-dive-into-spi/

Adam’s Favorite Tools: Heat Gun and Iron!
https://www.tested.com/making/tools/adams-favorite-tools-heat-gun-and-iron/

Opamp Interchangeability – Collin’s Lab Notes
https://youtu.be/sJB9wh91pxg

-=Digi-Key Spotlight=-

How to Calculate Resistor Bands – ATM: Quick Take
https://youtu.be/oc3TcoRb9ak

-=Transcript=-

This week on Maker Update, a robot that flings paint, an RC duck, a pocket-sized replicant detector, and a pumpkin for your Pi.

Hey everyone, I’m Donald Bell, and welcome back to another Maker Update. I hope you’re all doing well and finding some creative time. If you’re looking for your next project idea, you’ve come to the right place. Let’s get started, with the project of the week.

What do you do when you want to make a painting, but your inner perfectionist gets in the way? If you’re JBV Creative, you build a robot to throw paint at a canvas for you.

On his blog and YouTube channel he outlines the process he went through to create Flingbot — a 12-color, paint throwing, art machine.

This is a really fun build with a bunch of great features. I’ll start with the paint dispensers, which are 12 different inverted bottles that feed down into tubes.

Each tube is interrupted by a basic twist valve. But by adding a 3D printed geared collar around the tap, Jay can use a servo to twist it on or off and control exactly how much of each paint is being added to the mix.

Then there’s the catapult arm, which not only needs to swing around to collect the paint, but also needs to wind up and throw it, over and over again.

There’s a bunch of powerful servos at work here. One to wind the elastic reel, one to move it around to collect the paint, one to release the latch, and one more that uses fishing line to tension the custom made silicone cup that holds the paint.

And this is actually my favorite part of the project. After testing out the paint flinginging properties of a few different spoon shapes, Jay decided to make his own adjustable spoon. He used a 3D print to cast a design in silicone, which can change its shape by tensioning a bit of fishing line.

And he did all of this, just to add a bit of extra unpredictability to the paintings.

It’s a great project, and you can find more information, including the Arduino code, posted on the JBV Creative blog.

More projects. On Instructables, this project by Jude Pullen put a smile on my face. He shows how to thoughtfully mash-up a toy RC boat and a plastic duck decoy.

I’ve got a similar RC boat that my son and I take out on the water. It’s fun, but I expect it’s even more fun to operate a remote controlled duck.

Now, the basic idea is simple — you cut a hole in the bottom of the duck and your boat basically wears it like a costume.

But what’s great about someone like Jude doing this, who’s a product design engineer, is that you get to see how a mash-up like this can be done at the highest level.

By taking apart the toy, he’s able to cut a perfect outline of the boat into the duck.

But of course, you’ll still want access to the boat’s battery and electronics, so he carves out a lid from the top, and gives it a hinge using zip ties. He even adds a zip-tie loop on the duck’s back to make it easier to retrieve from the water.

I’m excited to give this hack a try.

On Twitter, I practically spit out my coffee after seeing this 3D printed, pocket-sized replica of the voight-kampff machine from Blade Runner.

The project is from James Brown, and it’s using a Raspberry Pi Zero, a Pi camera module, and a tiny CRT display pulled from an old camcorder viewfinder.

For the bellows, there’s a tiny linear servo that swipes back and forth.

I emailed James to learn more about the project and he told me that he has everything running off the Pi’s 5v input, including the mini CRT and the original driver board for it, which is the bit off to the right.

What’s even crazier to me is that he’s using OpenCV to do real-time eye-tracking which updates the screen with the cropped, live image of your eye. That’s a cool, creepy trick.

For another kind of creepy project that keeps its eye on you, check out this haunted pumpkin by Caleb Lemoine.

This one is also using a Raspberry Pi, along with a Pimoroni Pan-Tilt hat to move the pumpkin around.

To keep things relatively uncomplicated, two PIR sensors mounted on the sides are used to detect movement. Depending on the direction of the movement, the pumpkin head will turn to follow.

The movement is a little jerky in the video, but there’s some real potential here. I mean, you could replace the pumpkin head with any prop head or mask. Add a dash of animatronics or sound, and you could take this idea even further.

Now for some tips and tools. Through the Evil Mad Scientist blog I learned about SVGNest. This is an open source, browser-based tool for maximizing how many parts can be laser or CNC cut from a single sheet of material.

It includes settings that you can use to adjust the kerf space between objects, or whether or not to fit shapes within shapes. It’s quick, useful and free.

Through Hackaday I came across this deep dive video on SPI by Ben Eater. Ben’s done a number of great videos that go beyond how to use protocols or interfaces, and explores how and why they work the way they do.

Most of it is over my head, but SPI is such a common protocol for different sensors and Arduino breakouts, that I found it useful to get at least a slightly better understanding of what does what, and why.

On Tested, Adam Savage does a great job making the case for keeping a heat gun and an iron in your workshop.

I can’t say I’ve personally found irons to be useful very often, but I definitely get regular use out of my heat gun. When you need to pull something apart that’s held on with industrial adhesive, a heat gun is sometimes the only way to go.

But they’re also great for reforming or molding plastic–like when you’re trying to coax an RC boat into a plastic duck.

And on the Adafruit channel, Collin Cunningham has a quick video pointing out that, for all their variations, opamp chips have miraculously maintained the same pinout configuration.

You’ll still need to make sure the specs for voltage, impedance, and all that, but how great that you can reasonably expect the pin functionality to be the same if you need to drop in a replacement.

For this week’s Digi-Key spotlight, check out their latest Quick Take video on calculating resistor bands.

Not only is it a good refresher on what bands signal what values, but it’s also a good reminder that there’s a bunch of useful online tools you can access on DigiKey.com, including a resistor code calculator.

And that does it for this week’s show. Be sure to subscribe, leave a thumbs up or leave a comment. Let me know which project you liked the best this week?

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Thanks for watching, and I’ll see you soon.