Little FPV Bot Keeps It Simple With An ESP32

February 11, 2019 by Dan Maloney 9 Comments

When it comes to robots, it seems the trend is to make them as complicated as possible – look at anything from Boston Dynamics if you’ve any doubt of that. But there’s plenty to be said for simple robots too, such as this adorable ESP32-driven live-streaming bot.

Now it’s true that [Max.K]’s creation is more remote controlled car than robot, and comparing it to one of the nightmare-fuelling creations of Boston Dynamics is perhaps unfair. But [Max.K]’s new project is itself a simplification and reimagining of his earlier, larger “ZeroBot“. As the name implies, ZeroBot was controlled by a Raspberry Pi Zero, an obvious choice for a mobile platform designed to stream FPV video. The ESP32 bot eschews the Pi platform in favor of, well, an ESP32. To save as much space as possible, [Max.K] did a custom PCB for the microcontroller and its supporting components. The 3D-printed case is nicely designed to hold the board along with two motors, a small VGA camera, and a battery pack. At 160×120 resolution, the video isn’t amazing, but the fact that it can be streamed from the ESP32 at a decent enough framerate to drive the bot using a simple web interface is impressive.

This was a fun project and a very clean, smooth build. We like the lines of this little bot, and wouldn’t mind building one as a quick weekend project ourselves.

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An Arduino From The Distant Past

February 6, 2019 by Bryan Cockfield 20 Comments

Arduinos are a handy tool to have around. They’re versatile, cheap, easy to program, and have a ton of software libraries to build on. They’ve only been around for about a decade and a half though, so if you were living in 1989 and wanted to program a microcontroller you’d probably be stuck with an 8-bit microprocessor with no built-in peripherals to help, reading from a physical book about registers and timing, and probably trying to get a broken ribbon cable to behave so it would actually power up. If you want a less frustrating alternate history to live in, though, check out the latest project from [Marek].

He discovered some 6502 chips (Polish language, Google Translate link) that a Chinese manufacturer was selling, but didn’t really trust that they were legitimate. On a lark he ordered some and upon testing them he found out that they were real 6502s. Building an 8-bit computer is something he’d like to do, but in the meantime he decided to do a project using one of these chips as a general-purpose microcontroller similar to a modern Arduino. The project has similar specs as an Arduino too, including 8kB of RAM memory, 8kB of I/O address space, and various EPROM capabilities. [Marek] went on to build a shield board for it as well, for easy access to some switches and LEDs. It’s a great build that anyone interested in microcontrollers should check out.

Keep in mind that an ATtiny45 has 8 bits like the 6502 but only costs around $1 USD, whereas a 6502 would have cost around $200 in today’s dollars. It’s really only in modern times that we can appreciate the 6502 as a cheap 8-bit microcontroller for that reason alone, but we can also appreciate how it ushered in a computer revolution since competing Intel and Motorola chips cost around six times more before it showed up. They became so popular in fact that people still regularly use them to build retrocomputers of all kinds.

Back To Video Basics With An ESP32 VGA Display

February 5, 2019 by Dan Maloney 11 Comments

In a world where standards come and go with alarming speed, there’s something comforting about VGA. It’s the least common denominator of video standards, and seeing that chunky DB15 connector on the back of a computer means that no matter what, you’ll be able to get something from it, if you can just find a VGA cable in your junk bin.

But that’s the PC world; what about microcontrollers? Can you coax VGA video from them? Yes, you can, with an ESP32, a handful of resistors, and a little bit of clever programming. At least that’s what [bitluni] has managed to do in his continuing quest to push the ESP32 to output all the signals. For this project, [bitluni] needed to generate three separate signals – red, green, and blue – but with only two DACs on board, he had to try something else. He built external DACs the old way using R/2R voltage divider networks and addressed them with the I2S bus in LCD mode. He needed to make some compromises to fit the three color signals and the horizontal and vertical sync pulses into the 24 available bits, and there were a few false starts, but the video below shows that he was able to produce a 320×240 signal, and eventually goosed that up to a non-native 460×480.

It’s a pretty impressive hack, and we learned a lot about both the ESP32 and the VGA standard by watching the video. He’s previously used the ESP32 to build an AM radio station and to output composite PAL video, and even turned his oscilloscope into a vector display with it. They’re all great learning projects too.

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ESP8266 And Alexa Team Up To Tend Bar

February 4, 2019 by Tom Nardi 11 Comments

After a hard day of soldering and posting memes online, sometimes you just want to yell at the blinking hockey puck in the corner and have it pour you out a perfectly measured shot of your favorite libation. It might not be the multi-purpose robot servant we were all hoping to have by the 21st century, but [Jake Lee] figures it’s about as close as we’re likely to get for under fifty bucks or so (Jake’s security certificate seems to have expired a few days ago so your browser may warn you, here’s an archived version).

From the hardware to the software, his Alexa-enabled drink pouring machine is an exercise in minimalism. Not that there’s anything wrong with that, of course. The easiest solutions are sometimes the best ones, and we think the choices [Jake] made here strike a perfect balance between keeping things simple and getting the job done. It’s by no means the most complete or capable robotic bartender we’ve ever seen, but it’s perhaps the one most likely to be duplicated by others looking to get in on the voice-controlled drinking game.

So how does it work? For one, [Jake] didn’t go through the trouble of creating a “proper” Alexa skill, that’s quite a bit of work just to pour a shot of rum. Instead, he took the easy way out and used the FauxMo library on his ESP8266 to emulate a few WeMo smart switches. Alexa (and pretty much every other home automation product) has native support for turning these on and off, so with the proper code you can leverage it as an easy way to toggle the chip’s digital pins.

Using the Alexa’s “Routines” capability, these simple toggles can be chained together and associated with specific phrases to create more complex actions. For example, you could chain the dispensing alcohol, lowering the room lighting, and playing music all to a single voice command. Something like “I give up”, perhaps.

When Alexa tells the drink dispenser to turn on, the ESP8266 fires a relay which starts up a small 12 V air pump. This is connected to the bottle of rum though a glass tube that [Jake] bent with a blow torch, and starts to pressurize it. With the air at the top of the bottle pushing down on it, a second glass tube gives the liquid a way to escape. This method of dispensing liquid is not only easy to implement, but saves you from having to drink something that’s passed through some crusty eBay pump.

If you prefer the “right” way of getting your device talking to Amazon’s popular home surveillance system, our very own [Al Williams] can get you headed in the right direction. On the other hand, if the flowing alcohol is the part of this project that caught your attention, well we’ve got more than a few projects that cover that topic as well.

OpenISA Launches Free RISC-V VEGAboard

February 4, 2019 by Brian Benchoff 40 Comments

RISC architecture is gonna change everything, and I still can’t tell if we like that movie ironically or not. Nevertheless, RISC-V chips are coming onto the market, chipmakers seem really interested in not paying licensing fees, and new hard drives are shipping with RISC-V cores. The latest development in Open instruction sets chips comes from OpenISA. They’ve developed the VEGAboard, a dev board with two RISC-V chips and Arduino-style pin headers.

The VEGAboard comes loaded with an NXP chip which combines an ARM Cortex-M0 and Cortex-M4. So far, so good, but there are already dozens of boards that combine two ARM microcontrollers on a single development platform. The real trick is the RI5CY and Zero-RI5CY chips on the VEGAboard, a 4-stage RISC-V RV32IMCCXpulp CPU. This comes from the PULP platform, meant to be a small, low-power, but parallel platform for various processing needs. In short, with the VEGAboard, you’re not running a blink() sketch on the RISC-V microcontroller. You run the blink() sketch on the ARM microcontrollers, while using the RISC-V chip to read accelerometers and toggle pins. It’s a coprocessor, but it’s RISC-V.

Other features of the VEGAboard include 4MB of Flash, a light sensor, accelerometer, magnetometer, an RGB LED, OpenSDA serial debug adapter, an on-board BLE radio, and of course those wonky Arduino pin headers.

There are, or were, free VEGAboards available, but those are long gone. It’s still an interesting platform, though, and if you’d like to get your hands on one, production will resume shortly. Of course, if you need RISC-V right now, there are actual RISC-V Arduinos, a RISC-V with built-in neural networks, and SiFive will soon have a Linux-capable RISC-V multicore board. These are exciting times, and every day we’re seeing how RISC architecture is gonna change everything.

A 3D Printed Robotic Chariot For Your Phone

February 1, 2019 by Tom Nardi 6 Comments

As we’ve said many times in the past, the wide availability of low-cost modular components has really lowered the barrier to entry for many complex projects which previously would have been nigh-on impossible for the hobbyist to tackle. The field of robotics has especially exploded over the last few years, as now even $100 can put together a robust robotics experimentation platform which a decade ago might have been the subject of a DARPA grant.

But what if you want to go even lower? What’s the cheapest and easiest way to put together something like a telepresence robot? That’s exactly what [Advance Robotics] set out to determine with their latest project, and the gadget’s final form might be somewhat surprising. Leveraging the fact that nearly everyone has a device capable of video calls in their pocket, the kit uses simple hardware and 3D printed components to produce a vehicle that can carry around a smartphone. With the phone providing the audio and video link, the robot only needs to handle rolling around in accordance with the operators commands.

The robot chassis consists of a few simple 3D printed components, including the base which holds the phone and electronics, the wheels, and the two rear “spoons” which are used to provide a low-friction way of keeping the two-wheeled device vertical. To get it rolling, two standard DC gear motors are bolted to the sides. With the low cost of printer filament and the fact that these motors can be had for as little as $2 online, it’s hard to imagine a cheaper way to get your electronics moving.

As for the electronics, [Advance Robotics] is using the Wemos D1 Mini ESP8266 development board along with L298N motor controller, another very low-cost solution. The provided source code pulls together a few open source libraries and examples to provide a simple web-based user interface which allows the operator to connect to the bot from their browser and move it around with just a few clicks of the mouse.

If you like the idea of printing a rover to explore your living room but want something a bit more advanced, we’ve seen printable robotics platforms that are sure to meet your needs, no matter what your skill level is.

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Tiny Cheap ARM Boards Get WiFi

January 28, 2019 by Brian Benchoff 35 Comments

Over the last few years, we’ve seen the value of putting tiny WIFi-enabled microcontrollers on a module that costs a dollar or two. Those smart light bulbs in your house probably have an ESP8266 in them, and you can build a WiFi-enabled anything with one of these chips for next to no money. Now there’s a new module that takes the design philosophy of, ‘a reasonably powerful microcontroller, on a module, that does WiFi’ to its logical conclusion. It’s the W600 module from Seeed Studios. It’s got an ARM Cortex-M3, it’s FCC and CE certified, it’s got WiFi, and it’s cheap. This is what the people want, so somebody’s got to give it to them.

This product seems to be the followup and/or refinement of the Air602 WiFi Development board released by Seeed late last year. While the module itself grew a few more castellated pins and an RF can, the other specs look to be the same. Compared to the ESP-8266, which this module is obviously competing against, the Air600 is more than capable of pulling its own weight with five GPIO pins that do PWM, a decent amount of Flash, and all the WiFi support you could want.

The W600 is part of an entire family of boards, with the module itself readily available, but there’s also a few breakout boards that add connections for power and serial, a bigger breakout board that’s trying really hard to forget the pin misalignment of the Arduino Uno, and since this is Seeed, a board that connects to everything via Grove connectors. What’s a Grove connector? It’s power, ground, and either I2C or serial over a connector I couldn’t buy the last time I checked.

The W600 and its family of boards will be shipping shortly — China is shutting down for two weeks soon, after all — and there are plans for support for the Arduino IDE, Micropython, and an SDK for the tool chain of your choice.

Is the ESP8266 still the go-to for putting WiFi? Probably. But here’s some more competition.