For some power users, the one-hundred-and-something keys on regular keyboards just aren’t enough for their everyday tasks. Macro keypads are a popular way of extending one’s input capabilities, and there are almost as many examples as there are power users. [Ulrich]’s latest project, dubbed the LowPow E-Ink ShortKeyboard, is a beautiful and meticulously documented design for a macro pad that includes several unusual features.
Built around an ESP32-S3 microcontroller, the ShortKeyboard features nine programmable function keys plus an analog joystick and a rotary encoder. The keys are based on Cherry MX RED types commonly seen in mechanical keyboards, illuminated from below by by miniature RGB LEDs. A big e-ink display in the middle can be used to show the function of each key.
[elektroThing] is building a lightweight, battery-powered board to track and measure movement of all kinds, called Tracer. Powered by an ESP32, it has a LSM6DSL 6DoF accelerometer & gyroscope sensor, and a VL53L0X Time-of-Flight sensor. A small Li-ion battery in a holder reportedly provides for 5 hours of streaming data over Bluetooth Low Energy (BLE) at 100 Hz. It’s essentially a wireless movement sensor platform to be paired with a more powerful computer for data logging and analysis. What’s such a platform good for?
They show it attached to a tennis racket, saying you could use the data to, for a start, count the strokes done in a given match. They’ve also strapped it to a bicycle’s crankshaft and used it as a cadence sensor – good for gauging your cycling efficiency! But of course, this can be used in more applications than sport. A device like this could be used for logging movement of any relatively nearby objects, be it your cat, an office chair, or a door someone might slam a bit too hard at times. Say, you wanted to develop a sleep tracker and were to collect some data for defining your algorithms and planning your hardware requirements – this would work wonders.
There’s already available example code for streaming data into the Phyphox data logging and graphing app, as well as schematics – hopefully, the full board files will be available soon. A worthy open-source opponent to commercial devices available for similar purposes, this platform is good news for any hacker that wants to do motion measurement projects without reinventing quite a few wheels at once. We are told this board might get to CrowdSupply soon, and we can’t wait! Platforms like these, if done well, can grow an offspring of new projects for us to have fun with, and our paid projects get all that much easier to work on.
[Zhihui Jun] is a name you’re going to want to remember because this Chinese maker has created quite probably one of the most complete open-source robot arms (video in Chinese with subtitles, embedded below) we’ve ever seen. This project has to be seen to be believed. Every aspect of the design from concept, mechanical CAD, electronics design and software covering embedded, 3D GUI, and so on, is the work of one maker, in just their spare time! Sound like we’re talking it up too much? Just watch the video and try to keep up!
After an initial review of toy robots versus more industrial units, it was quickly decided that servos weren’t going to cut it – too little torque and lacking in precision. BLDC motors offer great precision and torque when paired with a good controller, but they are tricky to make small enough, so an off-the-shelf compact harmonic drive was selected and paired with a stepper motor to get the required performance. This was multiplied by six and dropped into some slick CNC machined aluminum parts to complete the mechanics. A custom closed-loop stepper controller mounts directly to the rear of each motor. That’s really nice too.
Stepper controller mounts on the motor rear – smart!
Control electronics are based around the STM32 using an ESP32 for Wi-Fi connectivity, but the pace of the video is so fast it’s hard to keep up with how much of the design operates. There is a brief mention that the controller runs the LiteOS kernel for Harmony OS, but no details we can find. The project GitHub has many of the gory details to pore over perhaps a bit light in places but the promise is made to expand that. For remote control, there’s a BLE-connected teaching device (called ‘Peak’) with a touch screen, again details pending. Oh, did we mention there’s a force-feedback (a PS5 Adaptive Trigger had to die for the cause) remote control unit that uses binocular cameras to track motion, with an AHRS setup giving orientation and that all this is powered by a Huawei Atlas edge AI processing system? This was greatly glossed over in the video like it was just some side-note not worth talking about. We hope details of that get made public soon!
Threading a needle through a grape by remote control
The dedicated GUI, written in what looks like Unity, allows robot programming and motion planning, but since those harmonic drives are back-drivable, the robot can be moved by hand and record movements for replaying later. Some work with AR has been started, but that looks like early in the process, the features just keep on coming!
Quite frankly there is so much happening that it’s hard to summarise here and do the project any sort of justice, so to that end we suggest popping over to YT and taking a look for yourselves.
Something like 99% of the people on the road at any given moment will consider themselves an above-average driver, something that’s as statistically impossible as it is easily disproven by casual observation. Drivers make all kinds of mistakes, but perhaps none as annoying and avoidable as failure to use their turn signal. This turn signal monitor aims to fix that, through the judicious use of negative feedback.
Apparently, [Mark Radinovic] feels that he has a predisposition against using his turn signal due to the fact that he drives a BMW. To break him of that habit, one that cost him his first BMW, he attached Arduino Nano 33 BLEs to the steering wheel and the turn signal stalk. The IMUs sense the position of each and send that over Bluetooth to an Arduino Uno WiFi. That in turn talks over USB to a Raspberry Pi, which connects to the car’s stereo via Bluetooth to blare an alarm when the steering wheel is turned but the turn signal remains untouched. The video below shows it in use; while it clearly works, there are a lot of situations where it triggers even though a turn signal isn’t really called for — going around a roundabout, for example, or navigating a sinuous approach to a drive-through window.
While [Mark] clearly built this tongue firmly planted in cheek, we can’t help but think there’s a better way — sniffing the car’s CANbus to determine steering angle and turn signal status comes to mind. This great workshop on CANbus sniffing from last year’s Remoticon would be a great place to start if you’d like a more streamlined solution than [Mark]’s.
[Larry Bank]’s Arduino library to print text and graphics on BLE (Bluetooth Low Energy) thermal printers has some excellent features, and makes sending wireless print jobs to a number of common models about as easy as can be. These printers are small, inexpensive, and wireless. That’s a great mix that makes them attractive for projects that would benefit from printing out a hardcopy.
It’s not limited to simple default text, either. Fancier output can be done using Adafruit_GFX library-style fonts and options, which sends the formatted text as graphics. You can read all about what the library can do in this succinct list of concise functions.
But [Larry] hasn’t stopped there. While experimenting with microcontrollers and BLE thermal printers, he also wanted to explore talking to these printers from his Mac using BLE directly. Print2BLE is a MacOS application that allows dragging image files into the application’s window, and if the preview looks good, the print button makes it come out of the printer as a 1-bpp dithered image.
Small thermal printers make for neat projects, like this retrofitted Polaroid camera, and now that these little printers are both wireless and economical, things can only get easier with the help of a library like this. Of course, if that’s all starting to look a little too easy, one can always put the thermal back in thermal printing by using plasma, instead.
Inside is an ESP32 running TensorFlow Lite to read in the gestures from the two touchpads. The pad at the top is a volume slider, and the square touchpad is the main input and is used in conjunction with the buttons to run AutoHotKey scripts within certain programs. [jakkra] can easily run git commands and more with a handful of simple gestures. The gestures all seem like natural choices to us: > for next media track, ∧ to push the current branch and ∨ to fetch and pull the current branch, s for git status, l for git log, and the one that sounds really useful to us — draw a C to get a notification that lists all the COM ports. One of the switches is dedicated to Bluetooth pairing and navigating menus on the OLED screen.
We love the combination of inputs here and think this looks great, especially with the double touchpad design. Be sure to check out the gesture demo gif after the break.
If you’re a reader of Hackaday, then you’ve almost certainly encountered an Espressif part. The twin microcontroller families ESP8266 and ESP32 burst onto the scene and immediately became the budget-friendly microcontroller option for projects of all types. We’ve seen the line expand recently with the ESP32-C3 (packing a hacker-friendly RISC-V core) and ESP32-S3 with oodles of IO and fresh new CPU peripherals. Now we have a first peek at the ESP32-C6; a brand new RISC-V based design with the hottest Wi-Fi standard on the block; Wi-Fi 6.
There’s not much to go on here besides the standard Espressif block diagram and a press release, so we’ll tease out what detail we can. From the diagram it looks like the standard set of interfaces will be on offer; they even go so far as to say “ESP32-C6 is similar to ESP32-C3” so we’ll refer you to [Jenny’s] excellent coverage of that part. In terms of other radios the ESP32-C6 continues Espressif’s trend of supporting Bluetooth 5.0. Of note is that this part includes both the coded and 2 Mbps Bluetooth PHYs, allowing for either dramatically longer range or a doubling of speed. Again, this isn’t the first ESP32 to support these features but we always appreciate when a manufacturer goes above and beyond the minimum spec.
Welcome to the ESP32-C6
The headline feature is, of course, Wi-Fi 6 (AKA 802.11ax). Unfortunately this is still exclusively a 2.4GHz part, so if you’re looking for 5GHz support (or 6GHz in Wi-Fi 6E) this isn’t the part for you. And while Wi-Fi 6 brings a bevy of features from significantly higher speed to better support for mesh networks, that isn’t the focus here either. Espressif have brought a set of IoT-centric features; two radio improvements with OFDMA and MU-MIMO, and the protocol feature Target Wake Time.
OFDMA and MU-MIMO are both different ways of allowing multiple connected device to communicate with an access point simultaneously. OFDMA allows devices to slice up and share channels more efficiency; allowing the AP more flexibility in allocating its constrained wireless resources. With OFDMA the access point can elect to give an entire channel to a single device, or slice it up to multiplex between more than once device simultaneously. MU-MIMO works similarly, but with entire antennas. Single User MIMO (SU-MIMO) allows an AP and connected device to communicate using a more than one antenna each. In contrast Multi User MIMO (MU-MIMO) allows APs and devices to share antenna arrays between multiple devices simultaneously, grouped directionally.
Finally there’s Target Wake Time, the simplest of the bunch. It works very similarly to the Bluetooth Low Energy (4.X and 5.X) concept of a connection interval, allowing devices to negotiate when they’re next going to communicate. This allows devices more focused on power than throughput to negotiate long intervals between which they can shut down their wireless radios (or more of the processor) to extended battery life.
These wireless features are useful on their own, but there is another potential benefit. Some fancy new wireless modes are only available on a network if every connected device supports them. A Wi-Fi 6 network with 10 Wi-Fi 6 devices and one W-Fi 5 (802.11ac) one may not be able to use all the bells and whistles, degrading the entire network to the lowest common denominator. The recent multiplication of low cost IoT devices has meant a corresponding proliferation of bargain-basement wireless radios (often Espressif parts!). Including new Wi-Fi 6 exclusive features in what’s sure to be an accessible part is a good start to alleviating problems with our already strained home networks.
When will we start seeing the ESP32-C6 in the wild? We’re still waiting to hear but we’ll let you know as soon as we can get our hands on some development hardware to try out.
Thanks to friend of the Hackaday [Fred Temperton] for spotting this while it was fresh!
