Author: Lewin Day

3315 Articles

A Robot Controller With The Compute Module 5

August 6, 2025 by 16 Comments

The regular Raspberry Pi line is a flexible single-board computer, but sometimes you might find yourself wishing for a form factor that was better designed for installation into a greater whole. This is why the Compute Module variants exist. Indeed, leveraging that intention, [Hans Jørgen Grimstad] has used the powerful Compute Module 5 as the heart of his “Overlord” robot controller.

The Compute Module 5 offers a powerful quad-core 64-bit ARM chip running at 2.4 GHz, along with anywhere from 2 to 16GB of RAM. You can also get it with WiFi and Bluetooth built in onboard, and it comes with a wide range of I2C, SPI, UART, and GPIO pins to serve whatever ends you envision for them. It’s a whole lot of capability, but the magic is in what you do with it.

For [Hans], he saw this as a powerful basis for a robot controller. To that end, he built a PCB to accept the Compute Module 5, and outfit it with peripherals suited to robotics use. His carrier board equips it with an MCP2515 CAN controller and a TJA1051 CAN transceiver, ideal for communicating in a timely manner with sensors or motor controllers. It also has a 9-axis BNO055 IMU on board, capable of sensor fusion and 100Hz updates for fine sensing and control. The board is intended to be easy to use with hardware like Xiaomi Cybergear motors and Dynamixels servos. As a bonus, there is power circuitry on board to enable it to run off anything from 5 to 36V. While GPIOs aren’t exposed, [Hans] notes that you can even pair it with a second Pi if you want to use GPIOs or camera ports or do any other processing offboard.

If you’re looking for a place to start for serious robot development, the Overlord board has plenty of capability. We’ve explored the value of the Compute Module 5 before, too. Meanwhile, if you’re cooking up your own carrier boards, don’t hesitate to let the tipsline know!

Australia’s Space Program Finally Gets Off The Pad, But Only Barely

August 6, 2025 by 42 Comments

Australia is known for great beaches, top-tier coffee, and a laidback approach to life that really doesn’t square with all the rules and regulations that exist Down Under. What it isn’t known for is being a spacefaring nation.

As it stands, a startup called Gilmour Space has been making great efforts to give Australia the orbital launch capability it’s never had. After numerous hurdles and delays, the company finally got their rocket off the launch pad. Unfortunately, it just didn’t get much farther than that.

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A Speed Loader For Your 3D Printer Filament

August 6, 2025 by 23 Comments

Reloading filament on a 3D printer is hardly anyone’s favorite task, but it’s even worse when you’re trying to shove stiff filament down a long and winding Bowden tube. Enter the speed loader from [Mr Flippant], which aims to take the pain out of this mechanically-frustrating chore.

The design is simple enough. It’s a small handheld tool that uses a 12 VDC gear motor to drive a set of Bondtech-style drive gears that you might find in an extruder. They’re assembled in a 3D printed housing with a microswitch to activate the motor, and a 9 volt battery to supply the juice.

To use the device, first thread the filament into the beginning of the Bowden tube. The idler gear is on a hinge, such that clamping it into position around the filament with the main gear activates the microswitch and turns the motor on, driving the filament all the way to the extruder. Job done! [Mr Flippant] notes that the filament should be as straight and unkinked as possible for best results, but that’s good advice when 3D printing in general.

Funnily enough, around these parts, when we talk about speed loaders, we’re usually discussing tapes.

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What Happens When Lightning Strikes A Plane?

August 5, 2025 by 24 Comments

Lightning is a powerful force, one seemingly capable of great destruction in the right circumstances. It announces itself with a searing flash, followed by a deep rumble heard for miles around.

Intuitively, it might seem like a lightning strike would be disastrous for something like a plane flying at altitude. And yet, while damage is possible, more often than not—a plane will get through a lightning storm unscathed. Let’s explore the physics at play.

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Spatial Audio In A Hat

August 5, 2025 by 5 Comments

Students from the ECE4760 program at Cornell have been working on a spatial audio system built into a hat. The project from [Anishka Raina], [Arnav Shah], and [Yoon Kang], enables the wearer to get a sense of the direction and proximity of objects in the immediate vicinity with the aid of audio feedback.

The heart of the build is a Raspberry Pi Pico. It’s paired with a TF-Luna LiDAR sensor which is used to identify the range to objects around the wearer. The sensor is mounted on a hat, so the wearer can pan the sensor from side to side to scan the immediate area for obstacles. Head tracking wasn’t implemented in the project, so instead, the wearer uses a potentiometer to indicate to the microcontroller the direction they are facing as they scan. The Pi Pico then takes the LIDAR scan data, determines the range and location of any objects nearby, and creates a stereo audio signal which indicates to the wearer how close those objects are and their relative direction using a spatial audio technique called interaural time difference (ITD).

It’s a neat build that provides some physical sensory augmentation via the human auditory system. We’ve featured similar projects before, too.

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A Simple Simulator For Model Rocket Performance

August 4, 2025 by 7 Comments

When building a model rocket, it can be fun to get into the maths of it all—calculating the expected performance of your build, and then seeing how it measures up in the real world. To aid in that task, [Rotislav Persion] has created a simple web-based simulator for charting the potential performance of your own rockets.

The calculator lets you key in the fundamentals of your hobby rocket. Punch in the diameter of your rocket, its mass, the standard rocket engine you’re using, and the diameter and delay time of your parachute, and it will chart the altitude profile expected during flight.

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Repairing An Obscure Apple II Clone

August 3, 2025 by 8 Comments

The Apple II was made in great numbers, as was the Commodore 64. But the Mimic Spartan? It was a weird Apple II clone that you needed a Commodore 64 to use. [ARC Javmaster] has found one of these obscure machines and has set about bringing it back to life. Check out the video below.

The story of the machine has been told online by one of the developers on the project, one [Brent Marykuca]. Basically, the Mimic Spartan was an Apple II clone that was intended to take advantage of a C64 as a host machine. It came in a beige box with a bunch of edge connectors and cables sticking out, and you were intended to nest it on the back of your C64 so it could hook up to all the ports. Then, you could use your machine as a C64 or an Apple II, or sort of… both… and even exchange data between both machines in some limited ways. There are also a few details of this obscure machine that have been collated by [Mike Naberezny], who is seeking the original disk that shipped with the machine when new.

It’s early days yet for [ARC Javmaster]’s efforts to restore the Mimic Spartan. Thus far, it’s had a clean and basic test. It was able to display a short line of text on a display before ceasing activity. A full boot hasn’t been achieved just yet, but we can’t wait to see where the resurrection efforts go next.

Back in the day, there were all kinds of Frankenstein computer cards that effectively put one kind of computer inside another. These days, you can condense an entire retro machine down to run on a single microcontroller.

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