robot

994 Articles

Cell Phone Surveillance Car

January 30, 2018 by 15 Comments

There are many viable options for home security systems, but where is the fun in watching a static camera feed from inside your place? The freedom to really look around might have been what compelled [Varun Kumar] to build a security car robot to drive around his place and make sure all is in order.

Aimed at cost-effectiveness and WiFi or internet accessibility, an Android smartphone provides the foundation of this build — skipping the need for a separate Bluetooth or WiFi module — and backed up by an Arduino Uno, an L298 motor controller, and two geared DC motors powering the wheels.

Further taking advantage of the phone’s functionality, the robot is controlled by DTMF tones. Using the app DTMF Tone Generator and outputting through the 3.5mm jack, commands are interpreted by a MT8870DE DTMF decoder module.While this control method carries some risks — as with many IoT-like devices — [Kumar] has circumvented one of DTMF’s vulnerabilities by adding a PIN before the security car will accept any commands.

He obtains a live video feed from the phone using AirDroid in concert with VNC server, and assisted by a servo motor for the phone is enabled to sweep left and right for a better look. A VNC client on [Kumar]’s laptop is able to access the video feed and issue commands. Check it out in action after the break!

Continue reading “Cell Phone Surveillance Car” →

Robotic Table Saw Automates Finger Joints

January 13, 2018 by 19 Comments

We’ve all seen finger joints or box joints, those interlocking puzzle pieces that make laser-cut plywood enclosures such a fixture for DIY projects. But laser cutters make finger joints look much easier to fabricate than they are with traditional woodworking tools, which often lead to disappointing results.

But this finger joint cutting robot is no traditional woodworking tool, and [timschefter] put a lot of work into building the rig. We have to admit that when we first saw the video below, the thought of having a table saw in our shop that could be turned on with a button on a phone gave us pause. But on closer analysis, it looks like safety was a major concern with this build. With a prominent e-stop and an interlock switch, the small table saw that forms the foundation of the robot should be safe enough. On the table top is a sled with a linear slide that moves the workpiece perpendicular to the blade, and the sled moves back and forth over the blade with pneumatic cylinders. The joint is set up with a custom app which calculates the pin width and spacing, which can be evenly distributed across the panel, or, for a bit of geeky fun, controlled to make a joint that encodes a message in Morse.

A lot of work went into this, and while it’s not the first robotic finger joint cutter we’ve seen, it’s pretty impressive. Now if it could only automate dovetails.

Continue reading “Robotic Table Saw Automates Finger Joints” →

Rolling Robot With Two Motors, But None Are On The Wheels

January 12, 2018 by 4 Comments

This unusual 3D printed Rolling Robot by [ebaera] uses two tiny hobby servos for locomotion in an unexpected way. The motors drive the front wheel only indirectly, by moving two articulated arms in a reach-and-retract motion similar to a breaststroke. The arms are joined together at the front, where a ratcheting wheel rests underneath. When the arms extend, the wheel rolls forward freely. When the arms retract, the wheel’s ratchet locks and the rest of the body is pulled forward. It looks as though extending one arm more than the other provides for rudimentary steering.

The parts are all 3D printed but some of them look as though they might be a challenge to print well due to the number of small pieces and overhangs. A short video (embedded below) demonstrates how it all works together; the action starts about 25 seconds in.

Continue reading “Rolling Robot With Two Motors, But None Are On The Wheels” →

Robotic Drive Train Is Nearly All 3D Printed

January 7, 2018 by 2 Comments

There are lots of ways to move a robot ranging from wheels, treads, legs, and even propellers through air or water. Once you decide on locomotion, you also have to decide on the configuration. One possible way to use wheels is with a swerve drive — a drive with independent motors and steering on each wheel. Prolific designer [LoboCNC] has a new version of his swerve drive on Thingiverse. The interesting thing is that it’s nearly all 3D printed.

You do need a few metal parts, a belt, two motors, and — no kidding — airsoft BBs, used as bearings. There are 3 parts you have to fabricate, which could take some work on a lathe, so it isn’t completely 3D printed.

[LoboCNC] points out that the assembly is lightweight and is not made for heavy robots. Apparently, though, his idea of lightweight is no more than 20 pounds per wheel, so that’s still pretty large in our book. The two motors allow for one motor to provide drive rotation while the other one — which includes an encoder — to steer. Of course, the software has to account for the effect of steering each wheel separately, but that’s another problem.

This robotic drivetrain is just thing for a car-like robot. If you are a little lonesome you could always print out ASPIR, instead. Or if you want an exotic 3D printed way to move things, you might get some inspiration from Zizzy. If you want a swerve drive that doesn’t require any machining or 3D printing, you might enjoy the video from another FIRST team, below.

Continue reading “Robotic Drive Train Is Nearly All 3D Printed” →

Remember When Scratch-Built Robots Were Hard?

January 2, 2018 by 10 Comments

Even simple robots used to require quite a bit of effort to pull together. This example shows how far we’ve come with the tools and techniques that make things move and interact. It’s a 3D printed rover controlled by the touchscreen on your phone. This achieves the most basic building block of wheeled robotics, and the process is easy on you and your pocketbook.

We just can’t stop loving the projects [Greg Zumwalt], aka[gzumwalt], is turning out. We just saw his air-powered airplane engine and now this little rover perks our ears up. The design uses the familiar trick of two powered wheels with a ball bearing to avoid problems with differential turning. But the simplicity is all in the implementation.

This bot is 3D printed using eight very simple pieces: four gears, two axles, a cap and a single tray to mount everything. The cap captures the ball bearing which pokes out a hole in the bottom of the tray to form an omnidirectional wheel. Two 9G servos modified for continuous rotation. The mating teeth of the gears are found on the wheel sections which have grooves for neoprene O-rings to provide traction. The entire thing is driven by an ESP8266 in the form of an Adafruit Feather Huzzah. This is programmed using the Arduino IDE and your phone can connect directly or through a WiFi router.

We’re not crazy, right? Robots didn’t used to be this easy to pull together? This goes for the power of 3D printing versus traditional basement fabrication methods, but in the availability of powerful yet inexpensive embedded systems and the available tools and libraries to program them. Kudos to you [Greg] for showing us how great the currently available building blocks are in the hands of anyone who wants to channel their engineering creativity. He certainly has… this chassis ultimately powers Santa’s sleigh.

Need a bigger printing challenge? Here’s a 3D printed rover that goes all-in with the suspension system.

Continue reading “Remember When Scratch-Built Robots Were Hard?” →

Much Assembly Required: Game Your Way To Assembly Guru Status

January 1, 2018 by 18 Comments

It can be hard these days to find an excuse to create something for learning purposes. Want a microcontroller board? Why make one when you can buy an Arduino or a Blue Pill for nearly nothing? Want to control a 3D printer? Why write the code when you can just download something that works well like Marlin or Repetier? If you want to learn assembly language, then, it can be hard to figure out something you want to do that isn’t so silly that it demotivates you. If that sounds like you, then you should check out Much Assembly Required.

This is a multi-player game that runs in your Web browser. But before you click close, consider this: the game has you control an autonomous robot using an x86-like assembly language. Your robots have to find resources and build structures so it is sort of a mash up of Minecraft and one of the many modern Hammurabi-inspired games like Civilization.

The robots have a variety of peripherals including: drills, lasers, LiDar, legs, a hologram projector, solar-charged batteries, clocks, and more mundane things such as clocks, floppy drives, and a random number generator. The virtual world simulates day and night, so plan your power management accordingly.

You might wonder if you should even bother learning assembly. While it is true it isn’t as necessary as it once was,  understanding what the computer is doing in a very basic way can help form your thinking in surprising ways. There are also those times when you need to optimize something in assembly and that’s the difference between working and not working.

If you want to do something more practical, we’ve looked at options before. Of course, you can always slip your C compiler some assembly, too.

Skelly the skeleton robot

Skelly The Skeleton Is A Scary Good Musician

November 30, 2017 by 14 Comments

There are a lot of things to like about [BoneConstructor]’s Skelly the skeleton robot project. Note that we said, “project”. That’s because not only does the robot work well and is built well, but the journey he took to make it contains steps we’ve all taken ourselves. We can say that with confidence since it’s his first, and we’ve all had those.

Skelly started life as a skeleton sitting in [BoneConstructor]’s antique race car at local car shows. Its eyes lit up and it made a moaning sound, which didn’t always work right.  From there came lessons learned with head and arm servos, followed by problems with a PS2 remote and a control board. When he realized he’d have to write his own code, he was stymied by his lack of programming skills. But then he found Visuino, which as you can guess from the name is a visual way to program Arduinos, mostly consisting of drag-and-drop. From there on, the path was smoother, if not completely linear.

Rather than rapidly burn through servos by mounting the bones directly to the servo arms, he fitted bearings into the bone sockets, put the limbs on shafts through those bearings, and used pusher rods connected to the servo arms to turn those shafts. It’s no wonder the arms work so well. He took that sturdy and resilient approach with the wrists and neck too. He even made its right foot able to tap in tune with the music.

And from there we begin to understand some of the method to his madness. Check out the videos below, and on his Hackaday.io page and you’ll see how wonderfully Skelly moves to the music. It even took a moment for us to realize he wasn’t actually playing the piano. But best of all, we like how he rocks out to AC/DC’s Shoot To Thrill (Iron Man 2 Version). We’re really impressed by how well those robot arms hold up given that this is a first robot.

Continue reading “Skelly The Skeleton Is A Scary Good Musician” →