Category Archives: Robot

A year of Robot Club

One late winter evening, a group of a dozen men and women gathered around a couple tables in the cramped upstairs of a hackerspace. It was the inaugural meeting of the Robot Club, and there had already been some lobbying and promoting of projects. It was generally deemed that the group should work on related projects so as to help each other. The front runner, and first project undertaken was the quadcopter.

This was an ambitious undertaking. We wanted these to be able to carry a GoPro, which meant it would be heavier and more expensive than typical learner flight craft. Though we weren’t experienced enough to know this at the time… After a few mad weeks of research, we had a BOM (Bill Of Materials) of something that might, in theory, fly. Ravi provided some much needed expertise with robotics and RC. John and Matt pulled together the specs, hoping that the calculations for propellers, motors, and battery would be okay. Parts were ordered to build 10, and the waiting began…

But while we waited, we invited people in to demo various robots and help us learn what might be needed. Ali demoed a robot from a UW Engineering class that does maze solving using ultrasonic sensors and SLAM (Simultaneous Localization and Mapping). One of the primary challenges of robotics: dealing with uncertain data and the disparity between reality and the model.

Many thanks to Jim, who put together a CopterVm, and presented a lot of research around which FOSS software to use for flight control.

When the parts finally arrived, we were able to assemble and they were able to fly with surprisingly few tweaks. The first few flights were just up, hover for a while, then land. We didn’t really expect it to go well, so it was still impressive…

A year of Robot Club A year of Robot Club

After a few test flights, some UFO sightings were reported. ☺

A year of Robot Club

Many tweaks were simply hacks, like soldering the right battery connectors, which didn’t match. There were a lot of neat innovations stemming from the original project! Ryan demonstrated the importance of not flying indoors. Neil designed a shock absorbing landing gear. Jim outfitted his with remotely dimmable lights. Enrico built an emergency parachute.

A year of Robot Club A year of Robot Club

A year of Robot Club A year of Robot Club

We flashed SimonK onto the ESCs — taking care as we discovered that some of these were the newer models with inferior response time, so we had to wait for a new version that didn’t cause these to melt and fall from the sky. Kanoa replaced the frame with a more rugged one and mounted both a FPV (remote First Person View) and GoPro.

A year of Robot Club A year of Robot Club

After the summer, the projects diversifies a little for two reasons: we didn’t want to fly in the cold and dark, and others were coming out with their robots. Chris has been working on a balance bot. David has made some really cool muscle controlled actuators. Shaun hacked a RC car to turn it into a bot. There have been multi leg walkers and several other robots.

A year of Robot Club

 

The winter project was a tiny robot, which autonomously does challenges. We only got around to doing some line following, though looked into several other sensors too.

A year of Robot Club A year of Robot Club

 

Here’s an ESP8266 hooked up to 9 axis sensors (accelerometer, gyroscope, magnetometer) sending the information to ROS.

A year of Robot Club

We’ve learned a lot about a lot of tech. We’ve used Arduino, Teensy, RaspPi, ESP8266, and MultiWii. Sensors include accelerometer, gyroscope, magnetometer, GPS, IR reflectance sensor, ultrasonic rangefinder. We’ve used 3D printers and a laser cutter. Software includes: ArduPilot, Robot OS, OpenSCAD, Vagrant, APM Planner, MAVProxy, mavlink, Linux, OpenCV (Computer Vision). Hope to have more frequent updates going forward!

A Sneak Peek at Some Interactive Show Installations

#drowning at Art Hack Day: Deluge. Photo by Margarida Malarkey

The sixth annual NYC Resistor Interactive Show is coming up this Caturday at 8pm. We have an overly generous baker’s dozen artists building a show fit for both organic and robotic party goers. We mentioned a few in our previous post, and here are a few more…

Our musical guest is plants! Not a band name, its actual plants that play instruments. Kirk Kaiser’s Plant Controlled Robot Bongos as well as Amy Cheng with her Plant Cyborgs are bringing the party, vegetation style, with their biohacks.

A Sneak Peek at Some Interactive Show Installations

Do you like ducks? What’s a party without ducks? How about robot ducks! We got one. Join the trip in Jakob Theileis’s Kinetic Robot Farm.

A photo posted by David Huerta (@huertanix) on

Are you the mutant savior? Find out at the Reformed Church of Robotron, by regional bishops Adam Mayer and David Huerta. It’s totally not the Church of Robotron from Oregon. They are heretics who have gone astray and we are the true church. You think otherwise, blasphemer? Beat our high scores to prove it!

The NYC Resistor Interactive Show is taking place on…

May 30th, 2015
8:00 PM ET – Late

…at…

NYC Resistor (between Bergen and Dean)
87 3rd Ave. Floor 4 (use this OSM link if you’re Richard Stallman)
Brooklyn, NY 11217

INTERACTIVE SHOW: May 30th 8PM, be there!

Mark your calendars! Our annual interactive art show fundraiser is coming up on May 30th and it’s going to be totally ~cyberbananas~. New York’s partiest interactive artists will be showing off their latest explorations into the future, sometimes with robots! Tickets sell out fast, so bump it up to 88 miles per hours and reserve yours today.

Tickets available online or at the door: $15

May 30th, 2015
8:00 PM ET – Late

NYC Resistor (between Berger and Dean)
87 3rd Ave. Floor 4 (use this OSM link if you’re Richard Stallman)
Brooklyn, NY 11217

Soft Robots for Hard Problems

What is a soft robot anyway? Over the last few weeks I’ve been giving demos at Resistor to show students what they are, what they’re good for, and how you can make your own.

Resistor was host to two meetup groups: the ACM NYC Group and the Soft Robotics Technology Group. During the demonstrations I gave a brief overview of the state of the art in soft robotics and then went into how I designed and built my most popular soft robot to date: the Glaucus.

Students helped out by casting waxes, degassing silicone, and pouring up molds themselves. Maybe soon I’ll come up with a way to get an even more hands-on demo where people can each make a bot themselves to take home.

Below you can find video from the ACM lecture:

 

3D printer experimentation into Steel Casting

In this post I outline my experimentation with 3D printing to produce a functional steel casting used in a battlebot.

The goal was to produce a steel part which would be too time consuming, expensive or near impossible to produce through conventional means. IE milling, welding, laser cutting etc. With metal casting you can make almost any shape, though the design I chose is a bit conservative…

For many years now I’ve been building robots, specifically R/C to semi-autonomous fighting robots. Robots which fight in competitions designed after the once popular TV shows Robot Wars and Battlebots. However the project covered here is probably the most involved I’ve ever gotten in building a weapon for one of my robots. Almost everything I do is a custom fabrication but this project is was something else entirely.

Before I get into details I should mention I am a Mechanical Engineer who specializes in Metal Casting, specifically steel. All the work seen here (with the exception of the 3D prints and grinding) was done at a steel foundry (Alloy Casting Industries, New Hamburg). Steel casting requires a great deal of energy and is inherently dangerous, while metal casting copper, bronze and aluminum is attainable to the maker community it can be very dangerous. Inhaling free silica can cause serious respiratory problems. As such please do not attempt at home.

First! We start with a 3D model of the part. I wanted a nice hammer for the over head hammer robot I was building, I aimed for a shape which would penetrate or buckle most armor while not getting stuck in either my opponent or the floor. I chose an arrow head type shape with a sharp tip and +45 degree angles on each piercing face.

Here is the rough 3D model, some changes were made prior to casting. This was done in Solidworks.
3D printer experimentation into Steel Casting

Now comes the 3D printing, I sectioned the part lengthwise to create a 2 piece pattern which later becomes the pattern for the casting. All parts were printed on a MakerBot in ABS at Kwartzlab. Shell and infill to flavor.

See the prints below, note the locater interlocks and the rectangular slots for mounting on the weapon arm.
3D printer experimentation into Steel Casting

The pattern fit together quite well with a little sanding of the locator pins. Some sanding was required to remove the steps typical of FDM 3D printing, also to reinforce the draft printed on the part. Draft is a slight angle to the direction of pull to allow the pattern to comfortably pull out from the sand.

The next step is to paint the pattern with a mold release agent, apply a fill and feeding system then pack it into sand. I used a typical cope & drag method where one half was packed into sand, the second piece located into it then sand packed around that. This separates the mold into 2 halves (or cope/drag) for cleaning and painting before finally being glued and closed.
Heres the concept:

3D printer experimentation into Steel Casting

Once the mold is together and the sand has set, its time to pour. Here is an image of the mold right after the steel has been poured. In its molten state this carbon steel alloy (with a touch of added chrome) is poured at 3000F/1650C.
3D printer experimentation into Steel Casting

*video of the pour

After the mold has cooled down and can be safely handled the part is shaken out and cleaned up a bit.
Here the part is right out of the sand after a bit of cleaning with a wire brush.
3D printer experimentation into Steel Casting
After the feeder has been cut off I weighed the part, I was aiming for 3lb. I think this is a telling shot, how accurate you can be with sand casting especially when a pattern is precision printed exactly to the original model.
3D printer experimentation into Steel Casting
After a bit of grinding the part went in for a heat treatment.
Here the part has been completely ground and polished a bit, looks dangerous….
3D printer experimentation into Steel Casting 3D printer experimentation into Steel Casting
Mounted and ready to break bots!

After welding the hammer to the mounting arm a series of post-weld heat treatments were applied to maintain the hardness.

3D printer experimentation into Steel Casting
The method I used here is a blend of conventional sand casting where in a physical pattern is created to then make a negative in sand, having a cope and drag (top/bottom) of the mold allows the pattern to be drawn out. It is also possible to utilize 3D printing to produce a PLA pattern, which can then be baked out of the mold medium. This is finding some ground in investment casting of jewelry and minor parts which typically use wax to generate a negative.

The reason I used a conventional method here is the unavailability of PLA printing at the time but also the temperatures requires to adequately bake out the PLA would likely damage the sand used. I am using Silica Sand with a polyurethane no bake resin binder. The binder acts as a glue to harden the sand to an almost concrete density.

Overall this project took me just around 2 hours, not including the printing which was done offline at night.

I look forward to further experimentation using 3D printing to support metal casting. At the forefront of blending technologies and industries is ExOne, a company which produces 3D printed sand parts and entire molds. Their products are actually quite nice, additionally 3D printed plastic patterns are finding some success with early adopters, including Alloy Casting Industries of New Hamburg ON.

-Ravi B
All Black Robotics @ KwartzLab

*Some details of metal casting, specifically the technical aspect of casting a dimensionally stable part are not included here simply to condense the article.

Robbie is safely enclosed!

Finished room!

Whew.  This project was a D-O-O-O-ZY!  We needed to enclose our giant industrial arm so he can’t run away and join the robot circus…

Well…maybe not for THAT reason, but when we start cutting stuff with this robot, we need to keep spectators out of his reach and make sure that if a cutting bit does break, it doesn’t go flying out into the shop and maim someone.

This entire project was the work of several people and really shows why the Milwaukee Makerspace is a great place to build stuff/hang out with friends/play with power tools, etc…

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Step 1: Design it!  I used Solidworks and modeled each and every piece of wood that went into this project.

SW screen capture

Step 2: get the wood!  We made multiple trips to Home Depot, which thankfully is only 5 minutes away and we had great weather during the whole building process.  I love having a truck!  Fortune also shined upon me, as we had a new member join up right before I started this project, Jake R., and his help in building the wall was immeasurable.

Get the wood!

Step 3: Bolt the wood to the floor so we know where to put the wall, and then build some framing!

  4 - put in windows

Step 4: Put in the windows, drywall paneling and metal wainscoting.  We were very lucky to get seven pieces of slightly-smoked Lexan from one of our members, Jason H.  We also cut small holes in the ceiling tiles and ran 4 braces up to the metal ceiling trusses above.  This enclosure is ROCK-solid stable!  Thanks to Tony W. and Jim R. for helping with that!

When I went to Home Depot, I thought my truck could handle a 48″x 120″ sheet of drywall.  Not so much… one of their employees helped me split 10 sheets of drywall in half, in the parking lot…so I would later find out that I did not have drywall tall enough for the wall corner.  Hence the need for more “framing” so I could use smaller pieces.

10 - outer framing

The large cabinet that powers the robot arm is right next to the enclosure; I placed it outside to keep it away from foam & wood shavings.  However, we will need to have the programming pendant next to the machine every now and then….hence the need for 2 small pass-thru doors next to the cabinet.

6 - hole for mini-door

11 - outer door installed

 

 

 

 

 

 

 

 

 

 

I used doweling to help hold the door frame components together…..probably not needed, but it ensures a STRONG door!

16 - drilling door frames  15 - door framing 1

Again, hooooray for the Makerspace and all its tools! We have several LONG pipe clamps that came in VERY handy for gluing the door frame pieces together.

17 - frame glued up - 1

Here’s the outside of the enclosure.  The big metal control cabinet will go right here, hence the framed “mouse hole” in the lower right corner so we can pass the cables through from the cabinet to the robot arm.

13 - outer door and mouse hole

The same area viewed from inside the enclosure.

14 - inner door and mouse hole

Here’s the ginormous sliding door.  It’s mounted on a barn-door track-rail and supported on the bottom by two custom-made wheel brackets.

23 - finished door on track

Here’s how I made the wheel brackets.  I got two lawnmower-style wheels and bearings from Tom G., then Tom K. enlarged the center holes on the wheels on his Bridgeport mill so I could use bearings for smoother action.

18 - wheels in slot - 1

I figured on four carriage bolts for a super-strong connection to the door frame.

19 - wheel assembly done

This is the track and wheel bogies that hold the sliding door to the wall.

22 - wheels and track

Bolting the brackets onto the door was “fun”…I forgot that the very bottom of the door framing is two horizontal pieces, so the very bottom bolt had to go.  ’DOH!

21 - inside door frame 1

Here’s the final, assembled view.  You can see the robot’s control cabinet in the lower right corner.

Now that the fabrication is complete, we’re working on decorative ideas for all that blank-looking drywall.

24 - finished room!

Whenever I look at this finished project it feels like to took several months to get it up, even though construction only lasted about 2-1/2 weeks.

Thanks to Jake R., Tom G., Tom K., Tony W., Jim R., and Bill W. for their assistance with this project!

Robbie is nearly weaponized….


router clamp in foam 2I am nearly done with a custom bracket for my Hitachi router that I will mount onto the end of our Kuka industrial robot arm.  I cut everything out in foam first to check  out the whole scheme and save wear and tear on the cutting bit.

flange for RobbieThe software chain I used to accomplish this was lengthy.  I designed all of these pieces in 3D in Solidworks, created a Solidworks 2D drawing, saved that as an AutoCAD drawing, brought that drawing into Vectric’s Aspire, then created machine code that the Makerspace CNC router used to cut the pieces from a sheet of foam.

finished clamp

Finally, once I was satisfied that everything would cut correctly, I switched to 3/4″ thick Baltic Birch plywood.  This is a “nicer” grade of plywood than the stuff that is used in day-to-day building construction work.  This wood is stronger by virtue of a greater number of plies, and it also looks nicer.  I happened to have a sheet left-over from a previous project, so it was all good!

plywood sheet

Photography Area Improvements!

We’ve had a dedicated photography area at the Makerspace since moving to our new building in January.  However, the lighting was powerful and direct, which resulted in some pretty exciting shadows.  Today, I set up four 400 watt equivalent, 105 watt (somewhat) compact florescent lights on stands that each have shoot through umbrella diffusers.  Check them out in room just off the craft lab.

Four_Photo_Stands_with_Umbrellas

Now we can take photos that aren’t a nightmere of shadows and hot spots!  Like this teaser photo of FIDO, shown below.  Stay tuned for more info on him!

Mystery_Project_witout_glare_or_shadows