DIY Tank Tracks Give Tons of Traction

If you’re building a robot for off-road or rough terrain, chances are you’ve thought about using a tank-tread style drive. There are a ton of kits available with plastic tread and wheels, but they are typically really expensive or pretty flimsy. Instead of going with an off-the-shelf solution, [Paul B] designed a heavy-duty tank tread made with common bike chain and conduit.

Some DIY tread designs we’ve featured just use a single bike chain on either side of the tread pieces. This gets the job done, but each section of tread is usually bolted through the chain. This means that you can’t use a sprocket to drive the chain since all the bolt heads block where the teeth engage. Instead, these designs typically use drive wheels inside the tread, which are prone to slip under a heavy load. [Paul B]’s design is a bit different: it uses a DIY double-wide chain so he can bolt tread segments to the chain and still use a drive sprocket.

Constructing the double-wide chain took quite a bit of work. [Paul B] completely disassembled a couple of bike chains with a delinker tool and then reassembled the chain in a double-wide configuration with M3 bolts instead of the original chain pins. Each section of tread (made out of cut pieces of plastic conduit) bolts on the outside section of chain, and a sprocket runs on the inside. His DIY chain approach saves him money too, since double-wide chains are pretty expensive. Since his sprockets directly engage the drive train, his design should be able to handle as much torque as his drivetrain can put out.

Open Source, DIY Soldering Robot

After [Brian] starting selling his own Raspberry Pi expansion boards, he found himself with a need for a robot that could solder 40-pin headers for him. He first did what most people might do by looking up pre-built solutions. Unfortunately everything he found was either too slow, too big, or cost as much as a new car. That’s when he decided to just build his own soldering robot.

The robot looks similar to many 3D printer designs we’ve seen in the past, with several adjustments. The PCBs get mounted to a flat piece of aluminum dubbed the “PCB caddy”. The PCBs are mounted with custom-made pins that thread into the caddy. Once the PCBs are in place, they are clamped down with another small piece of aluminum. A computer slowly moves the caddy in one direction, moving the header’s pins along the path of the soldering irons one row at a time.

The machine has two soldering irons attached, allowing for two pins to be soldered simultaneously. The irons are retracted as the PCB caddy slides into place. They irons are then lowered onto the pins to apply heat. Two extruders then push the perfect amount of solder onto each pin. The solder melts upon contact with the hot pins, just as it would when soldered by hand.

The system was originally designed to be run on a Windows 8.1 tablet computer, but [Brian] found that the system’s internal battery would not charge while also acting like a USB host. Instead, they are running the Windows WPF application on full PC. All of the software and CAD files can be found on [Brian’s] github page. Also be sure to check out the demo video below. Continue reading “Open Source, DIY Soldering Robot”

The BB-8 Builds Begin

Yes, the new Star Wars film coming out in December has x-wings, dogfights through the engines of star destroyers, space battles, a dead Jar Jar, and [R2D2]. It will also have the coolest droid yet, [BB-8], the rolling sphere protagonist that will surely be sold as a remote control toy by Christmas 2016.

[James] of XRobots doesn’t want to wait until the [BB-8] toys arrive, so he’s building his own. Right now, it’s just a prototype, but it’s the beginnings of the mechanics and control system of a very, very cool droid.

We’ve seen the first BB-8 droid that was basically putting some magnets on a Sphero robot, but this bot doesn’t exactly have the same functionality of the real-life [BB-8]. The real [BB-8] is actually two parts, a remote control ball-body, and a separate remote-controlled head. [James] is focusing on the head for his prototype, replacing the remote-controlled body with a dummy stand in, a big styrofoam ball.

The head of [James]’ [BB-8] is 3D printed, with some especially clever design features. The electronics are just four DC motors, an Arduino, and some motor drivers. In the future [James] will probably be looking at either steppers or servo motors, but for now his [BB-8] bot can stand up straight and serves as a great platform for testing out control schemes.

All the code and parts are available on Github, with some videos below.

Continue reading “The BB-8 Builds Begin”

Strong Little Robots With Gecko Technology

If you need to build a robot to carry something, you need a bit motor, right? Not so with these tiny robots out of Stanford’s Biomimetic Dexterous Manipulation Laboratory. One of these 12g MicroTugs can drag a 600g mug of coffee across a table, or even a 12kg weight. According to the authors, it’s a, ‘capability … comparable to a human dragging a blue whale.’ Square-cube law notwithstanding, of course.

What makes these little robots so strong? It’s not the actuators; it’s their feet. On the bottom of this robot is a material that uses mechanical anisotropic adhesion, a fancy material that only sticks to flat surfaces when it’s being pulled in a specific direction.

The best description of this material inspired by gecko feet would be this video, also from the Stanford BDML lab. It’s a neat material that we’ll probably find in Post-It notes in a decade, and with a single motor, a tiny robot can lift thousands of times its own body weight.

Videos below. Thanks [Adrian] for the tip.

Continue reading “Strong Little Robots With Gecko Technology”

Mini BB-8 Droid Made from a Sphero

Hot on the heels of discovery that the BB-8 Droid from the new Star Wars movie is real, [Christian Poulsen] has made the very own miniature version of it!

It’s a brilliantly simple hack actually. Remember the Sphero? It’s a remote controlled ball you can drive around with your phone — great fun, but surprisingly not many people have hacked it…

The ball has an internal structure that allows it to roll around with ease. Which also means it has a fixed up direction — at least inside of the ball. All [Christian] had to do was crack it open and throw a magnet on the top of the inner-assembly. He then machined the droid’s head out of foam with another magnet (or metal, we’re not too sure) and boom-bada-bing it stays in place as the ball rolls.

Stick around after the break to see some GIFs of it adorably rolling around — and into things.

Continue reading “Mini BB-8 Droid Made from a Sphero”

BB-8 is real! But how did they do it?

BB-8 the new droid in the star wars franchise made his first public appearance (YouTube link) at Star Wars Celebration last week. While cast and crew of the movie have long said that BB-8 is real, seeing it up on stage, driving circles around R2D2 takes things to a whole new level. The question remains, how exactly does it work?

new petOur (and probably any other tech geek worth their salt’s) immediate reaction was to think of xkcd’s “New Pet” comic. All the way back in 2008, [Randall Munroe] suggested omnidirectional wheels and magnets could be used to create exactly this kind of ‘bot. Is this what’s going on inside BB-8? No one knows for sure, but that won’t stop us from trying to figure it out!

BB-8’s family tree may actually start with Sphero. Fortune reports  that Sphero was part of Disney’s accelerator program in 2014. Each company in the accelerator program gets a mentor from Disney. Sphero’s mentor was Disney CEO Bob Iger himself.

The Head

So if BB-8’s body is based on a Sphero, how does the head work? The Disney crew has been mum on this so far, but there is plenty of speculation! If you watch the video in HD, several flashes can be seen between the body and head gap. These might be status LEDs on BB-8’s electronics, but they could also be IR LEDs – possibly part of an optical mouse style sensor. Sensor fusion between gyroscopes, accelerometers and the optical flow sensors would make for a robust solution to the inverted pendulum problem presented by BB-8’s head.

How do you think BB-8 works? Is it magnets, motors, or The Force? Let us know in the comments!

Continue reading “BB-8 is real! But how did they do it?”

Robotic Player Guitar Rocks Out on Its Own

Back in 1988 [Ben Reardon] walked through the Japanese pavilion at the World Expo held in Brisbane, Australia. He saw a robot playing a classical guitar, and was in awe. Later in his life, he decided to learn guitar, and always thought back to that robot. After going to SIGGRAPH 2014 and being inspired by all the creative makers out there, he realized the technology was here — to build his own Robot Guitar.

He started small though — with a prototype robotic Tambourine. It helped flush out some of the ideas for coding that he would eventually employ on the Robot Guitar. The guitar features both an Arduino and a Raspberry Pi, along with six RC servos — one for each string. The biggest challenge with the project was getting the servos mounted just right — stiff, but with adjustment so each pick could be tuned for identical timing. He ended up using aluminum extrusion to mount the servos, three per side in order to leave space for the picks.

Once the mechanical portion was done — onto the coding…

In the end, it ended up being only 460 lines of code. Python and a bit of Bash for the Raspberry Pi — and of course a few sketches for the Arduino. But enough talking about it — let’s hear it!

Continue reading “Robotic Player Guitar Rocks Out on Its Own”