Project Giant Robot Arm

December 26, 2015 by James Hobson 21 Comments

[Antoniopenamaria] is working on a giant robot arm. The beauty is, he’s posting a step-by-step guide (translated) of his entire journey from start to finish.

Why does he want to build a giant robot arm? Well, the idea originally came to him a few years ago when he was soldering something together and thought, “Man, I could really use another hand!”. So he got out a Meccano set, and built a mini robot arm. Nothing fancy, but it worked. From there, he decided to program it, and was able to teach it to move things from point A to point B… as he continued to expand on his little project, the vision grew, and now he’s working on project D.I.M.E.R. — a giant robot arm.

Continue reading “Project Giant Robot Arm” →

Human Gestures Control This Robot Arm

July 31, 2015 by James Hobson 1 Comment

[Ray Kampmeier] just finished writing some code to allow him to control his robotic arm using force-sensitive hand gestures! He calls it the Robo Marionette.

He’s using a MeArm 4 DOF robotic arm, a Sensel touch interface, an Arduino Uno, and a servo shield for the Arduino to control the MeArm. All the code you need is available on his GitHub, but unfortunately the Sensel touch interface isn’t actually available to the public yet.

Continue reading “Human Gestures Control This Robot Arm” →

3D Mouse Drives Robot Arm

July 28, 2015 by Al Williams 17 Comments

You’ve built the perfect robotic arm. How do you drive it? If you are [angrymop] you interface a 3D mouse from 3DConnexion via a few microcontroller boards. The Spacenavigator mouse is a staple anywhere professional CAD people are working, and it looks like it is a natural fit for a robot arm.

According to [angrymop], the Raspberry Pi can read the mouse’s commands via /dev/hidraw (that’s the raw human interface device). Each motion generates two lines of output. Each line has a unique identifying byte and values corresponding to the axis positions.

The Raspberry Pi then uses an SPI interface to talk to an ARM microcontroller and that drives the servos. The arm (the robot arm, not the processor) itself is well done, made from Lego Technic parts and common RC servos. Not that this is the most amazing thing we’ve ever seen built from Technic, but it is still pretty impressive.

You have to wonder if other 3D controllers might be useful for controlling robot arms or how the Spacenavigator would do controlling a bigger, more capable arm. Then again, maybe this arm would be the right size to build something inspired by Escher.

Continue reading “3D Mouse Drives Robot Arm” →

6-Axis Robot Arm 3D Prints A Metal Bridge

June 13, 2015 by James Hobson 22 Comments

Do you remember the MX3D metal printing robot? It’s now capable of 3D printing a metal bridge. Here’s the news release, but it’s in Dutch (translated).

Over one year ago we covered the beginning of the MX3D project, which was a rather ambitious foray into 3D printing in metal with a industrial six-axis ABB robot arm. They had previously done a version using resin (MX3D Resin Printer), but then upgraded the system to use a heavy duty welding machine to deposit various metals.

One year later, they’ve tuned it even more. To show it off they printed a free form standing bridge that people can actually walk across.

Continue reading “6-Axis Robot Arm 3D Prints A Metal Bridge” →

My Robot Army @ Maker Faire

June 2, 2015 by Sarah Petkus 13 Comments

For a few years now I’ve been developing an interactive army of delta robots. This ongoing project is fueled by my desire to control many mechanical extremities like an extension of my body (I’m assuming I’m not the only one who fantasizes about robots here).

Since my army doesn’t have a practical application… other than producing pretty light patterns and making the user feel extremely cool for a minute, I guess you’d call it art. In the past I’ve held a Kickstarter to fund the production of my art which I can now happily show at cool events with interesting people; Maker Faire being one of them.

Interactivity and Sprawling Crowds

Last year, for our debut at the big Bay Area Maker Faire, my collaborator, [Mark], and I displayed a smaller sampling of 30 robots for our installation. We also decided to create an interactive aspect for others to experience. After the end of our crowdfunding period last March, we had a little over a month to do any development before the big event, so our options were slim. The easy solution was to jam our delta code into the hand tracking demo which comes with the Xbox Kinect’s Open NI within Processing. This was cool enough to exhibit, but we hadn’t really anticipated how it would go over in an environment as densely packed as the dark room at Maker Faire.

We should have known better. Both of us were aware that there would be many, many children… all with micro hands to confuse and bewilder the Kinect, but we did it anyway. Our only resolve was to implement the feature that would force the Kinect to track one hand at a time, only after being waved at in a very particular fashion. After needing to explain this stipulation to every person who stopped by our booth over the course of the weekend, we decided never to use the Kinect for crowds ever again; lesson learned.

Delta Robots and DMX

Over the past year since that experience, we’ve tripled the size of the installation and brainstormed some better demo ideas. As of now, the robots are all individually addressable over an RS485 bus, and we use the DMX protocol over a CAT5 cable to send commands. If you aren’t familiar with it, DMX is used in show production to control stage lighting… to which there is a super neat and free application called QLC+ that allows you to effectively orchestrate the motion and color of many individual light units; perfect for our cause.

Functionally, each of the 84 delta robots in the installation believes that it is a stage light (robots with identity issues). We mapped the X and Y axis of the end effector to the existing pan and tilt values, and the z axis to the beam focus value. The RGB of the LED mounted in the end effector of each delta maps directly to the RGB value of the stage light.

By using the sliders in the QLC+ GUI, I could select groups of robots and create presets for position and color. This was great, someone like me who doesn’t really write a lot of code could whip up impressive choreography with little sweat. Additionally, the program comes with a nice visualizer, where you can layout virtual nodes and view your effects as you develop them.

This is the layout of our installation mapped in QLC+. The teal and purple sliders around each light represent pan and tilt (or in our case X and Y):

Lighting control was an interesting solution. Having autonomous robots this year changed how people responded to them, as they were less like an army you’d command and more of a hypnotic field of glowing grass.

[Mark] and I are considering picking up some flex sensors and maybe playing with the Leap or an EEG headset as a means to reintroduce the interactive aspect. Bottom line, I have this cool new toy that I can’t wait to play with over the summer!

Continue reading “My Robot Army @ Maker Faire” →

Robot Arm Wields Laser, Cares Not For Your Safety

April 1, 2015 by Rich Bremer 44 Comments

Here at Hackaday we’ve covered a bunch of DIY laser diode projects. And for good reason, they are just cool. We’ve seen people add lasers to their 3D printers, stick one in a milling machine, use a highly modified scanner and even build a simple XY gantry specifically for the task. To say the least there is definitely a wide range of methods for moving around a laser but we’ve never seen anything like what [Sp4rky] sent in to us. He and his friends outfitted an old educational robot arm with a laser.

The robot arm is a 5 axis Armdroid 5100 picked up from eBay for a couple hundred dollars. It didn’t come with a controller but all of the stepper drivers were housed in the base of the arm. After a little tinkering around with the inputs the team was able to get the arm to move by sending serial commands from a PC, through an Arduino Mega which then sends the appropriate signals to the uni-polar stepper drivers. That was the easy part of the build.

The hard part was getting the arm to hold the laser at a consistent angle and height above the table. Inverse Kinematics to the rescue! Since the desired position of the laser, as well as the length of the arm segments is known, mathematical formulas can be derived to determine the necessary arm segment and joint positions while moving the laser around. The process flow starts out with an image in Inkscape, g-code is then generated with this plugin, then sent to the Arduino running a modified version of GRBL that has the inverse kinematic formulas. The Arduino directly controls the stepper drivers and the robotic arm moves. The Arduino also controls 3 constant-current laser drivers made from LM317 regulators. Three laser drivers, why?

[Sp4rky] got his laser diode modules out of surplus medical equipment and, unfortunately, the rated optical wattage was quite low. Since he had 3 diodes, he decided to try to combine the 3 low power beams into one high power beam. This can be done using a prism. A prism splits sunlight into a rainbow of colors because each wavelength(color) of light that passes through the prism is bent a different amount. Since the laser diodes only put out one wavelength of light, the beam bends but does not split or diffuse. A 3D printed bracket points each laser diode at a 3-sided pyramidal prism which sends the combined beam of light straight out the bottom towards the object to be cut or engraved.

This project is cool enough that we would have covered it even if [Sp4rky] wasn’t burning a Hackaday logo. Although it doesn’t hurt for anyone wanting their project to get covered!

A Recycled Robot Arm For All!

March 28, 2015 by James Hobson 10 Comments

It’s mind boggling how much e-waste we throw out. Perfectly good components, mass produced for pennies. And at the end of their life, going straight to a landfill or some poor country to be melted down. Don’t you wish you could help?

Stepper motors are a dime a dozen when it comes to e-waste, and there’s tons of cool projects you can do with a stepper motor — [Madivak] is just starting on a robot arm design over at Hackaday.io that makes use of recycled components.

It’s fairly early in development, but that means it’s a great time to start following it on the project site. The robotic arm is being designed for his final year project in his undergrad degree. Besides the steppers, he’s using his school’s Utilimaker 3D printer to manufacture all of the other mechanical components with control coming from DRV8825 stepper drivers and the Freescale Freedom KL25Z dev kit. Check out the clips after the break to see current state of the build.

Continue reading “A Recycled Robot Arm For All!” →