pic32

75 Articles

2D-Platform Seeks Balance With A Touch Screen

January 4, 2020 by 17 Comments

It’s the [Bruce Land]-iest season of all, when the Cornell professor submits the projects his microcontroller class students have been working on all semester. Imagination does not seem to be in short supply with these students, and we always look forward to these tips this time of year.

[Greg] and [Sam]’s touch-screen two-dimensional ball balancer is a good example of what [Land]’s students turn out. The resistive touch screen is supported by a 3D-printed gimballed platform and tilted in two axes by hobby servos. [Greg] and [Sam] chose to read the voltage outputs from the touch screen directly using the ADC on a PIC32, toggling between the two axes at 2 kHz. Two PID control loops were implemented to keep the ball as centered as possible on the platform, and the video below shows that there’s still some loop tuning to do. But given the positional inaccuracies of hobby servos and the compliance in the gimbal, we’re impressed that they were able to keep the system under control at all.

Of course we’ve seen ball-balancers before, but most of them have closed the loop using either cameras or microphones. Seeing direct sensing on the platform like this is a nice change of pace. Continue reading “2D-Platform Seeks Balance With A Touch Screen” →

Team Scores Big Points With Pinball Final Project

December 25, 2019 by 6 Comments

For their final project in [Bruce Land]’s class on designing with PIC32 microcontrollers, [Sujith], [Julia] and [Andrew] wanted to do something fun. And what could be more fun than bending to the electromechanical siren song of the pinball machine?

This machine looks great, and as you can see in the demo video after the break, it plays and sounds great, too. We particularly like the boomerang obstacle and the game state-driven LED strip. The more points you score, the brighter they go. We also like that this machine combines traditional scoring methods with a few really clever ones, like the boomerang target near the top and the scoring triggers made from copper tape.

The team started by designing the heart of any pinball machine, the flippers. Though we have seen car door lock actuators used in homebrew machines, the team went with traditional solenoids to drive them. Unfortunately the solenoids caused a lot of interference, but the team got around it with filter capacitors and aluminium foil Faraday cages around the wires.

If all this pinball talk has your circuits lit up, why not try making your own machine? Continue reading “Team Scores Big Points With Pinball Final Project” →

Vintage Console Becomes The Calculator It Appears To Be

August 25, 2019 by 9 Comments

What’s sitting on [Bob Alexander]’s desk in the video below did not start out life as the desktop calculator it appears to be. Turning it into a standalone calculator with features the original designers couldn’t imagine turned out to be an interesting project, and a trip down the retrocomputing rabbit hole.

A little explanation is in order. Sure, with its Nixie display, calculator keypad, and chunky mid-century design, the Wang 360 desktop console looks like a retro calculator. But it’s actually only a dumb terminal for a much, MUCH bigger box, called the Electronic Package, that would fit under a desk. The foot-warming part that was once connected to [Bob]’s console by a thick cable that had been unceremoniously lopped off by a previous owner. [Bob] decided to remedy the situation with modern electronics. The console turned out to have enough room for a custom PCB carrying a PIC32, some level-shifting components, power supply modules that include the high-voltage supply for the Nixies, and a GPS module because Nixies and clocks just go together. The interesting bit is the programming; [Bob] chose to emulate the original Wang methods of doing math, which include multiplication by logarithmic addition. Doing so replicates the original look and feel of the calculator down to the rapid progression of numbers across the Nixies as the logarithms are calculated using the display registers.

We normally frown on vintage gear being given modern guts, but in this case [Bob] hit just the right balance of new and old, And given that the Electronic Packages these consoles were connected to go for $1500 or more on eBay, it was a better choice than letting the console go to scrap. A similarly respectful approach was taken with this TRS80 Model 100 revival.

Continue reading “Vintage Console Becomes The Calculator It Appears To Be” →

Tweetbot Expresses Twitter Emotions

March 16, 2019 by 3 Comments

When reading textual communications, it can be difficult to accurately acertain emotional intent. Individual humans can be better or worse at this, with sometimes hilarious results when it goes wrong. Regardless, there’s nothing a human can do that a machine won’t eventually do better. For just this purpose, Tweetbot is here to emotionally react to Twitter so you don’t have to.

The ‘bot receives tweets over a bluetooth link, handled by a PIC32, which also displays them on a small TFT screen. The PIC then analyses the tweet for emotional content before sending the result to a second PIC32, which displays emotes on a second TFT screen, creating the robot’s face. Varying LEDs are also flashed depending on the emotion detected – green for positive emotions, yellow for sadness, and red for anger.

The final bot is capable of demonstrating 8 unique emotional states, far exceeding the typical Facebook commenter who can only express unbridled outrage. With the ‘bot packing displays, multiple microcontrollers, and even motor drives, we imagine the team learned a great deal in the development of the project.

The project was the product of [Bruce Land]’s ECE 4760 course, which has shown us plenty of great hacks in the past – Bike Sonar being one of our favorites. Video after the break.

Continue reading “Tweetbot Expresses Twitter Emotions” →

Laser Harp Sounds Real Thanks To Karplus-Strong Wave Equation

December 29, 2018 by 9 Comments

The harp is an ancient instrument, but in its current form, it seems so unwieldy that it’s a wonder that anyone ever learns to play it. It’s one thing to tote a rented trumpet or clarinet home from school to practice, but a concert harp is a real pain to transport safely. The image below is unrelated to the laser harp project, but proves that portable harping is begging for some good hacks.

Concert grand harps are so big there’s special equipment to move them around. This thing’s called the HarpCaddy

Enter this laser harp, another semester project from [Bruce Land]’s microcontroller course at Cornell. By replacing strings with lasers aimed at phototransistors, [Glenna] and [Alex] were able to create a more manageable instrument that can be played in a similar manner. The “strings” are “plucked” with the fingers, which blocks the laser light and creates the notes.

But these aren’t just any old microcontroller-generated sounds. Rather than simply generating a tone or controlling a synthesizer, the PIC32 uses the Karplus-Strong algorithm to model the vibration of a plucked string. The result is very realistic, with all the harmonics you’d expect to hear from a plucked string. [Alex] does a decent job putting the harp through its paces in the video below, and the write-up is top notch too.

Unique musical instruments like laser harps are far from unknown around these parts. We’ve seen a few that look something like a traditional harp and one that needs laser goggle to play safely, but this one actually looks and sounds like the real thing. Continue reading “Laser Harp Sounds Real Thanks To Karplus-Strong Wave Equation” →

Microcontroller And IMU Team Up For Simple Flight Sim Controls

December 23, 2018 by 3 Comments

Classes are over at Cornell, and that means one thing: the students in [Bruce Land]’s microcontroller design course have submitted their final projects, many of which, like this flight control system for Google Earth’s flight simulator, find their way to the Hackaday tips line.

We actually got this tip several days ago, but since it revealed to us the previously unknown fact that Google Earth has a flight simulator mode, we’ve been somewhat distracted. Normally controlled by mouse and keyboard, [Sheila Balu] decided to give the sim a full set of flight controls to make it more realistic. The controls consist of a joystick with throttle, rudder pedals, and a small control panel with random switches. The whole thing is built of cardboard to keep costs down and to make the system easy to replicate. Interestingly, the joystick does not have the usual gimbals-mounted potentiometers to detect pitch and roll; rather, an IMU mounted on the top of the stick provides data on the stick position. All the controls talk to a PIC32, which sends the inputs over a serial cable to a Python script on the PC running Google Earth; the script simulates the mouse and keyboard commands needed to fly the sim. The video below shows [Sheila] taking an F-16 out for a spin, but despite being a pilot herself since age 16, she was curiously unable to land the fighter jet safely in a suburban neighborhood.

[Bruce]’s course looks like a blast, and [Sheila] clearly enjoyed it. We’re looking forward to the project dump, which last year included this billy-goat balancing Stewart platform, and a robotic ice cream topping applicator.

Continue reading “Microcontroller And IMU Team Up For Simple Flight Sim Controls” →

PIC-Powered Game Console Is Blocky Goodness

December 19, 2018 by 5 Comments

Picking up new skills in the electronics field is often best served by the classic mantra – “learn by doing”. [Juan] and [Leo] did just that, deciding to build a handheld game console for a University project, and delivering the PGC-32.

Built as a final project for the Digital Systems Design course at Cornell University, the PGC-32 takes on a daunting chunk of functionality, and pulls it off in time to get the grades. The team coded a basic block-based game for the hardware, and control is switchable between the analog stick and a built-in accelerometer. Gameplay is displayed on a 320 x 280 color TFT display. Learning to code a basic game is useful, as it teaches student engineers to consider important concepts like timing, race conditions, interrupts, and display routines.

As a university project, it is well documented and the team step through each detail in their code with explanations as to how and why things are done. The internals are particularly neat, too, with a tidy PCB layout and 3D printed case holding everything together.

We’ve seen plenty of work from Cornell’s courses before, too – like this sleep quality monitor.  Video after the break.

Continue reading “PIC-Powered Game Console Is Blocky Goodness” →