Solving A Rubik’s Cube With Just Two Motors

December 2, 2017 by Dan Maloney 11 Comments

We’ve all seen videos of Rubik’s cube champions who can solve the puzzle in less than 5 seconds. And there are cube-twisting robots that can solve the cube even faster, often in under a second. This Rubik’s cube solver is not one of those robots, but it’s still pretty cool.

The reason we like Dexter Industries’ “BricKuber” is not for its lightning speed — it takes a minute or two to solve the puzzle. What we like is the simplicity of the approach to manipulating the cube. Built from LEGO parts, including Mindstorms motors and a BrickPi controller, the BricKuber uses only two motors to work the cube. One motor powers a square turntable upon which the cube sits, while the other powers an arm that does double duty — it either clamps the cube so the turntable can rotate a layer, or it rakes the cube to flip it 90° on the turntable. With a Pi Cam overhead, the rig images all six faces, calculates a solution to the cube, and then flips and twists the cube to solve it. It’s simultaneously mind-boggling and strangely relaxing to watch.

All the code is open source, and we strongly suspect a similar and possibly faster robot could be built without the LEGO parts. You might even be able to build one with popsicle sticks and an Arduino.

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Raspberry Pi Robot That Reads Your Emotions

November 17, 2016 by Steven Dufresne 8 Comments

It’s getting easier and easier to add machine intelligence to your hacks, even to the point where you sometimes don’t have to install any special software. In this case [Dexter Industries] has added the ability to read human emotions to their EmpathyBot robot by making use of Google Cloud Vision.

Press a button on the robot and it moves forward until it’s a certain distance from an object. It then takes a picture and sends it off to Google Cloud Vision along with a request to do face detection. The response that Google returns is in JSON format and, if it finds a face, includes the likelihood of the face being happy, sad, sorrowful or surprised. The robot parses that response and gives an appropriate canned speech using the text-to-speech software, eSpeak e.g. “You seem happy! Tell me why you are so happy!”.

[Dexter] has made the source code available on github. It’s written in python and is easy to read by anyone with even just a little programming experience. The video after the break gives a number of demonstrations, including some with non-human subjects.

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Sort Your Candy With A Raspberry Pi And Google Cloud Vision

October 31, 2016 by Jenny List 15 Comments

If you have been off trick-or-treating and returned home with an embarassment of candy, what on earth can you do to mange the problem and sort it by brand?

Yes, it’s an issue that so many of us have had to face at this time of year. So much a challenge, that the folks at [Dexter Industries] have made a robotic candy-sorter to automate the task.

OK, there’s something of the tongue-in-cheek about the application. But the technology they’ve used is interesting, and worth a second look. Hardware wise it’s a Lego Mindstorms conveyor and hopper controlled by a Raspberry Pi through the BrickPi interface. All very well, but it’s in the software that the interest lies. They use the Raspberry Pi’s camera to take a picture to send off to Google Cloud Vision, which they then query to return a guess at the brand of the candy in question. The value returned is then compared to a list of brands to keep or donate to another family member, and the hopper tips the bar into the respective pile. They provide full build details and code, as well as the video we’ve put below the break. So simple a child can explain it, sort of.

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Lego NXT Creations Are Even Cooler With WiFi On Board

November 12, 2011 by Mike Nathan 2 Comments

nxt-wifi

The folks at Dexter Industries have just wrapped up a week of Lego NXT projects, most of which centered on the use of their NXT WiFi sensor. Developed over the last few months, the group has been hard at work refining their design and getting some of the kinks worked out, so now you too can control your NXT creations sans wires.

The demonstrations have covered various topics throughout the week, starting out with a short tutorial on how to use a computer to communicate with the NXT device using the TCP protocol. After taking a look at WiFi power-saving capabilities, they touched on pinging other networked machines as well as querying DNS records from an NXT device. An NXT-based webserver was the next project on the list, as was remote robot control over the Internet. Finally, they wrapped the week up by configuring their Lego robot to send a tweet.

If getting your NXT creations on the move with full-fledged network access is something that sounds interesting, be sure to check out their site for downloads, a WiFi manual, and more.

Friday Hack Chat: Training Robots By Touch

August 1, 2018 by Brian Benchoff 3 Comments

When it comes to training robots, you could grab a joystick or carefully program movements in code. The better way, though, is to move the robot yourself, and have the robot play back all those movements ad infinitum. This is training robots by touch, and it’s the subject of this week’s Hack Chat over on hackaday.io.

Our guest for this week’s Hack Chat will be [Kent Gilson], inventor, serial entrepreneur, and pioneer in reconfigurable computing. [Kent] is the creator of Viva, an object-oriented programming language and operating environment that harnesses the power of FPGAs into general-purpose computing He’s launched eight entrepreneurial ventures, won multiple awards, and created products used in numerous industries across the globe.

[Kent]’s claim to fame on hackaday.io is Dexter, a low-cost robotic arm with 50-micron repeatability and modular end effectors. It does this with three harmonic drives and optical encoders that give it extreme precision. The arm is also trainable, meaning that you can manually control it and play back the exact path it took. It’s training robots by touch, exactly what this Hack Chat is all about.

For this Hack Chat, we’re going to be discussing:

Building trainable robots
Developing robotics haptics
Training robots to manufacture
Heterogenous direct digital manufacturing

You are, of course, encouraged to add your own questions to the discussion. You can do that by leaving a comment on the Hack Chat Event Page and we’ll put that in the queue for the Hack Chat discussion.

Our Hack Chats are live community events on the Hackaday.io Hack Chat group messaging. This week is just like any other, and we’ll be gathering ’round our video terminals at noon, Pacific, on Friday, July 27th. Need a countdown timer? Well, here you go, mango.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io.

You don’t have to wait until Friday; join whenever you want and you can see what the community is talking about.

BrickPi Bookreader 1 And 2 Read Tablets Or Books Aloud, You Choose

May 10, 2014 by Rich Bremer 10 Comments

BrickPi Bookreader 2

Have you ever wanted to relax with a good book but couldn’t due to the hassle of having to actually read and turn pages? Well, now BrickPi offers 2 solutions to that problem. They have you covered regardless if your document is on a tablet or resides in a physical book.

The original Bookreader will read out loud the displayed text on a tablet. brickpi bookreader This is not an application that runs on the tablet, it is a completely separate device that ‘reads’ the tablet screen. As you could guess from the BrickPi name, the brains behind the operation is a Raspberry Pi. A camera takes a photograph of the displayed text and the Raspberry Pi converts that image file to text using Optical Character Recognition. A Text-to-Speech engine then speaks the text in a robotic sounding voice. In order to change the page the Raspberry Pi controls a Lego Mindstorms arm that swipes across the tablet screen and the entire process is repeated.

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LEGO ROV Without A Tether

August 14, 2012 by Mike Szczys 13 Comments

[Brane] built an underwater ROV from LEGO mindstorm parts. Look closely at this image and you should notice something missing. The tether that normally carries power and control lines from an ROV to the surface is missing. This is a wireless solution that lets him control the device using an Xbox controller.

The video after the break shows about five minutes of test drive footage. [Brane] has a big aquarium in which he can test the thing. Since he put it together as his senior engineering project at University it’s likely that this is a testing facility at the school. Here’s the little we know about the hardware: It’s using NXT Mindstorm parts to control the motors, with a sealed chamber for a battery. Connectivity is provided by an XBee module with an NXT adapter board called the NXTBee. A laptop with its own XBee module makes up the other end of communications. Right now [Brane] uses an Xbox controller connected to the laptop, but a standalone device would be easy to build by hacking the XBee and controller together directly.

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