Blog Posts

Expensive Notes has been using Novation Launchpad USB Ableton controllers in a novel way, connected to a Teensy 4.1 via USB Host rather than using the intended DAW.

The Launchpad becomes a large 8×8 RGB LED “screen” for the Teensy, as well as an input device, while the Teensy can interface with other devices over MIDI. And in this particular example, rather than sequencing or performing with the Launchpad, notes are controlled by Conway’s Game of Life cellular automata simulation algorithm.

The connected Korg Volca Bass and FM receive notes based on cells dying and being born respectively. The game can also be re-seeded with new cells in order to alter the pattern. MIDI clock is sent to all connected devices to keep everything in sync, including a Volca Drum. Hear the automata in action in the video below!

Shiny Quagsire (Max Thomas) chose an extremely ambitious project for his high school final project: rather than creating something using the many VR hardware solutions out there, he decided to create his own VR controllers from the ground up.

The eventual solution utilized a Teensy 3.2 with TDK MPU-9250 nine-axis gyro/accelerometer/compass sensors, in a PlayStation Move-like form factor, but using infrared.

The initial attempt used pure IMU data, which proved infeasible due to poor sample rates and accuracy. Switching to a camera and LEDs whose position could be triangulated improved things, but what proved superior to this was diffusing IR LEDs via styrofoam spheres and using the resultant 2d circle to determine X/Y position, and its size to approximate Z. The entire journey can be relived in detail on Shiny Quagsire’s Tumblr, and the source code and STLs can be found on GitHub.

Expensive Notes was given a broken Dalek (toy, not an actual homicidal mutant!), which, as is their wont, meant turning it into a synth! Based on a Teensy 4.1 and Audio Adaptor Board, the psychopathic cyborg is now polyrhythmic thanks to Expensive Notes’ creative mods.

The mutant’s antennae and arms have been connected to potentiometers and joysticks to adjust parameters such as sequence length. Dalek-bump buttons are enabled by Adrian Freed’s FastTouch library. Get ready to party like it’s a Kaled family reunion with Expensive Notes’ synth jam demo below!

“Will it run DOOM!?” And as emulator maker extraordinaire Jean-Marc has now proven (and to be honest you may have already inferred from this post’s title), the answer is a resounding “OH YES”!

So, how did Jean-Marc squeeze all those demons and BFGs onto a Teensy 4.1? An STM32 port of Chocolate Doom certainly helped, as well as the fact that he had already developed a VGA driver. USB keyboard support, while it does not include complete mapping, allows you to enjoy the game as it should be: with arrow keys.

Source code and so much more can be found in the M.CU.M.E (Multi CompUter Machine Emulator) GitHub repo, along with information on the many other games and platforms supported by the project.

We’ve all seen videos of Boston Dynamics’ robot “dog” Spot dancing, but $75K is a lot to spend. Enter Aaed Musa’s Traverser of Planar Surfaces (or “TOPS” – “SPOT” backwards!) which can get just as funky at less than 1/20th of the cost!

The project, which was inspired by James Bruton’s openDogV3 robot, took four months to build, at a cost of around $3,300. It features twelve custom high-torque actuators, a 3d-printed planetary gearbox, a carbon fiber frame, a 6S 5200mAH LiPo battery, and of course, a Teensy 4.1. Code, schematics, and BOM can be found on GitHub, with more detail on Aaed’s web site and Hackaday. And most importantly, you can regard its sweet moves in the video below!

Alex Toussaint created an ultrasonic 3d scanner using off-the-shelf components for under $100!

What was your fantasy when you were 15? For Alex it was an autonomous drone that could deliver cans of Coke, which he reasoned would require a 3D map of its surroundings. Ruling out LiDAR as too expensive, and Simultaneous Localization and Mapping (SLAM) algorithms as insufficient, perhaps something could be done with an ultrasonic sensor, since humans are able to pinpoint locations based on sound? The result of this theory, which Alex reached at the grand old age of 19, he achieved this 3D sensor goal.

The detailed write-up on Alex’s site explains the concept, math, and various stages of success and failure, but the end result was a 10×10 grid of emitters with a 9x directional receiver based on LM386 amplifiers.

The resultant scans, while perhaps not perfect, are frankly incredible for a device built from scratch. Source code, schematics, and visualization scripts can all be found on GitHub if you’d like to build your own!

Jay Ackley has created a collection of musical devices called the NoPlay Digital Instrument Suite.

As Jay’s ambitions grew, it became clear that the simple saw wave output of the original microcontroller he was using was not going to work for his more advanced creations, which led him to dive into the world of Teensy and the Audio Adaptor Board.

The resulting Electrolute Mach 3 is a guitar-like instrument which allows the player to select a chord from one group of buttons and arpeggiate over the corresponding pentatonic scale with the other, using one of six different voices. Another device, the polyphonic Teensy LC-based Chordulator, plays first, third, fifth, and octave notes using pressure-sensitive resistors to affect the volume. Finally, the Teensy 3.5-bsed DrumTray percussion sequencer provides four 16-note tracks with adjustable swing, a 12-note 3/4 mode, and the all-important “party mode” which strobes all 64 RGB LED buttons. See them all in action in the video below!

Andy Meyer pilots experimental aircraft pilot and was in need of a good engine monitor to show key metrics on a sunlight readable screen.

After struggling for years with an Arduino-based project, Andy discovered Teensy and paired it with a NewHaven 4.3 inch 800×480 serial display…and it was all blue skies from there!

The current solution is based around a Teensy 3.6 with eight Type K thermocouples plus analog pressure and temperature sensors.

Oil temperature and pressure, manifold pressure, engine timing and RPM, are all currently measured and output to a 3.5″ capacitive touch display. Fuel flow, airspeed, altitude, and other values from the plane and GPS are also incorporated, with outputs for warning lights and a dimmer. Data is also logged to the onboard mSD card.

In true maker fashion, Andy designed the boards in Upverter and fab’d them through OSH Park, and designed the housing in OnShape and printed it on his Prusa i3 MK3. The inspirational finished product (for now!) can be seen mounted in the cockpit below.

Andy’s journey to make this engine monitor and many of the challenges are explained on this forum thread.

Adding new features to old computers is one of our favorite project types, as it keeps hardware out of the trash and gives the device a new lease on life.

Philip Freidin’s description of the EBTKS project certainly sounds like it has been an incredible journey, and the functionality that it adds to the HP-85 is positively mind-blowing.

A brief overview of the EBTKS’ features includes:

• tape drive emulation, using a 16GB mSD card to hold up to 200,000 tapes
• floppy and Winchester disk drive emulation via mSD
• ROM, RAM and Extended memory emulation
• jumperless configuration via text file
• over 70 new keywords
• an EPS32 co-processor (under development)

Find out more and order yours on the EBTKS web page.

Trip replaced the internals of a 1K mouse with a Teensy 4.0 for 8 times faster updates!

A 4K gaming mouse doesn’t mean it has four times as many pixels as a 1080p display — but rather that it polls at 4000Hz, meaning my movements are sent to the connected PC 4000 times per second. And just like TVs, 8K mice are already starting to be seen in the market.

Paired with a Pixart PMW3360DM-T2QU image sensor, which captures images at a rate of up to 12000 fps, the integrated Teensy transmits movement up to 8000 times per second over a shortened USB cable, in order to optimize transmission. More information can be found on the project’s GitHub page.