Introducing WaterColorBot 2.0

WaterColorBot 2.0

We are very pleased to introduce something that we’ve been working on for most of this year: WaterColorBot version 2.0!

WaterColorBot 2.0

The WaterColorBot is our collaboration with Super Awesome Sylvia: A friendly art robot that moves a paint brush to paint your digital artwork onto paper, using a set of watercolor paints.

Version 2.0 brings it to the next level with some greatly improved hardware. First and foremost, the carriage that holds the brush has been completely redesigned:

WaterColorBot 2.0

The carriage on the original WaterColorBot was made from laser-cut plywood, with nylon bushings and two simple delrin strips that formed the vertical flexure translation stage. (You can read more about the original carriage here and here.)

The new carriage consists mainly of two pieces of metal. The center block of anodized aluminum is CNC milled, and houses crossed linear roller bearings. Wrapped around that is a laser-cut and formed aluminum part that mounts the brush-lift motor, cable guide, and the flexure stage.

WaterColorBot 2.0

The new flexure stage is built with two custom flex circuit boards, used in this case as mechanical flexures. Each board consists of a very thin (0.1 mm, 4 mil) Kapton sheet with a thin fiberglass (G10/FR4) stiffener on its center section. With the two ends of each sheet clamped rigidly and the stiffener in the center, each flex circuit is to flex only along two well-defined lines. And with two boards, it forms a neat parallelogram linkage, without the slop that one might encounter in multi-part hinges. The net effect is that this new flexure stage has remarkable stiffness compared to the old design.

WaterColorBot 2.0

That stiffness, combined with the improved performance of the linear ball bearings makes this a more precise WaterColorBot. Not that you could even detect the improvement with a fat brush and watercolor paints, but things are looking quite good even with using ultra-fine point drawing pens, as you can see above.

WaterColorBot 2.0

The second major change is to the system of Spectra cords that the stepper motors control in order to move the carriage. Previously, the cords were guided around 11 plain bearings (stainless steel solid rivets) and 3 ball bearings.  We’ve simplified this into an arrangement of just 8 ball bearings— four for each motor. The ball bearing pulleys have also been updated to use wide V-groove bearings that are easy to wrap the cords around.

Which brings us to the third (and last) major change. Thus far, WaterColorBot kits have shipped “some assembly required” — with all the major components built, but the cord lacing left to the end user. As of 2.0, WaterColorBot kits now come fully assembled and tested. That doesn’t make them any less hackable, but it does mean that you can get up and running faster.

WaterColorBot 2.0

Version 2.0 includes the same CNC machined aluminum winches that we introduced back in August. Tiny detail: we’ve carved a subtle indentation into the wood around the winch that makes them a little easier to turn by hand.

WaterColorBot 2.0

The new WaterColorBot kits will begin to ship right after Thanksgiving. And a bonus present for the holiday season: Version 2.0 is priced the same as the previous version, it’s just a whole lot more awesome per dollar.

Introducing the EggBot Pro

EggBot Pro

An EggBot is a compact, easy to use art robot that can draw on small spherical and egg-shaped objects. The EggBot was originally invented by motion control artist Bruce Shapiro in 1990. Since then, EggBots have been used as educational and artistic pieces in museums and workshops. We have been working with Bruce since 2010 to design and manufacture EggBot kits, and our well-known Deluxe EggBot kit is a popular favorite at makerspaces and hackerspaces around the world.

Today we’re very proud to release the newest member of the family: the EggBot Pro, a near-complete reimagining of the EggBot, designed for rigidity, ease of use, and faster setup.

EggBot Pro

The EggBot Pro is as sturdy as can be: Its major components are all solid aluminum, CNC machined in the USA, and powder coated or anodized. (And isn’t it a beauty?)

The most common mechanical adjustments are faster with twin bicycle-style quick releases, and repositioned thumbscrews for easier access.

EggBot Pro

The frame also has an open front design that gives much better visibility while running, and greatly improved manual access when setting up.

EggBot Pro

And, it comes built, tested, and ready to use — no assembly required.  Assuming that you’ve installed the software first, you can be up and printing within minutes of opening the box.

The EggBot Pro begins shipping this week. We’ve also put together a little comparison chart, so you can see how it fits in with the rest of the family.

 

Linkdump: August 2014

New Winches for WaterColorBot

We’ve just given the WaterColorBot a little bump up to kit version 1.5. The new version now comes with a pair of beautifully machined aluminum winches.

The winches are precision cut on CNC machines and anodized clear. We add a few extra little parts (flat-head rivets to wind the winch around, screws, and a stamped and polished stainless steel “clamp” to hold the string end), and wind them with the same “100 pound” Spectra cord as we did before.

We described the process of making and winding our older laser-cut wooden winches in our blog post about the making of the WaterColorBot, and again in our post about the  winch cutting jig. For better or worse, transitioning to the new aluminum means that we’re no longer using our older wooden winches that we described in those blog posts.  But in the end, these new winches are a better, more elegant solution.

 WaterColorBot kit version 1.5 is now shipping from the Evil Mad Scientist Shop.

Electro-Kistka: Dyeing an Egg in Place?

Kistka-brush 11

In our annoucement article about the EggBot Electro-Kistka — the hot wax dispenser for the EggBot — we noted that it can be challenging to reposition an egg after taking it out to dye the egg between wax layers.

As an alternative suggestion, reader Dan commented:

Could you leave the egg in the EggBot and paint on the first layer(s) of dye with a brush? Then dip the egg for the last layer to get the ends covered.

Well, let’s try and see how it turns out!

Continue reading

Open Discussion: Best Practice for Mislabeled Open Source Projects?

non-oshw

In looking around for examples of great open source hardware projects, we came across an unexpected number of projects and products labeled as open source hardware that, upon closer inspection, actually turn out not to meet the definition. Often, they’re using an inappropriate license— typically a “non-commercial license,” which is not only unenforceable but explicitly incompatible with open source values. Sometimes, they haven’t released the design files. Sometimes, a person has apparently misused the term “open source” to mean “closed and proprietary.” And sometimes you might see the open hardware logo used without any substance to back it up.

But what (if anything) can or should be done about it? We’d like to solicit your input as to the best ways to approach this problem.  Perhaps there are not any easy answers.

As a baseline, we think that it’s important to address the problem, and to do so earlier rather than later. To mislabel a product for sale as open source hardware may constitute false advertising, illegal in the US under state and federal law. In noncommercial projects where nothing is for sale, misusing the terms may help to set precedent that can damage the community’s understanding of open source. For instance, if enough people see non-commercial licenses on things labeled as be open source, they may assume that it is acceptable.

If you happen to know someone behind the project, you might consider contacting them directly to start a dialog about what it means for something to be “open source.”  Or, you could (hint hint hint) send them a link to this article, letting them know that you found it interesting!

But, what if you don’t have any personal connections to the people involved? It’s certainly not as easy. Sometimes you can initiate a dialog with a company, perhaps by asking about their design files or licenses. At the other end of the spectrum, people sometimes bring up options like public shaming. In our view, shaming is harmful to the open source community, and should be considered a last resort akin to violence. Rather, we as a community need to work towards positive ways to nudge people toward doing the right thing.

Please let us know what you think: what should you do when you come across a project mislabeled as open source hardware?

The Incredible Computer-Controlled … Computer!

wcb-surface 7

A guest post by Daniel Gentleman 

About a year ago, I started working on a project that used robotics to control a Surface Pro tablet. Not long after I started, I got my first glimpse at the the WaterColorBot on display at Maker Faire Bay Area 2013. The WaterColorBot is designed to carry a paintbrush over a piece of paper, raising and lowering it as needed to paint a picture. The movement and software control is similar to CNC router with special design modifications to make it lighter, cheaper and easier to control. A CNC router has to move heavyweight cutting bit with friction so needs expensive motors, rails, and belts. The WaterColorBot, on the other hand, needs only to move a paintbrush in a low friction environment.

I was instantly sold on the idea of using a WaterColorBot to control the Surface. I backed the Kickstarter, waited for my bot to arrive, and started working on software. When the WaterColorBot arrived, I was not disappointed. The assembly was quick and I was robotically painting in no time.

With the big mechanical and electronic solutions solved, my attention turned to the tablet. The Surface Pro is rare among tablets in that it uses a digitizer that allows extremely precise tracking with a stylus along with “hover” and “right-click” functionality. It does not need to be electrically grounded like a stylus for a screen that only supports capacitive touch. I was certain that the Surface Pro was the way to go, but not quite how it was going to be held together. The project was about to take a another serendipitous turn.

 

wcb-surface 1

The custom-cut spoilboard

At this point, I shared my enthusiasm with Windell and Lenore of Evil Mad Scientist and they gave me a unique offer: Stop by the Evil Mad Scientist shop and together we would make a custom cut spoilboard (lower deck) fitted to mount the Surface Pro 2. Wielding digital calipers and other measurement and software tools, Windell came up with a design that held the tablet firmly and had extra space cut out for the charger, power button, and USB cable.

wcb-surface 2
wcb-surface 3 wcb-surface 4

The area beneath the tablet has a lip and a lower recessed area. This design reduces wobble and makes it look even better. On the topic of machining – I got a few lessons in how larger CNC machines work. Windell showed me some design considerations in software and gave me a safety briefing about the CNC router itself. This thing can cut fast.

After a little sanding, we fitted the tablet, spoilboard, and WaterColorBot together. Having the co-creators of the WaterColorBot with me on this journey was priceless, as we can see from the final assembly. The first spoilboard we cut matched perfectly and the tablet is held firmly in place.

wcb-surface 6

With enthusiasm fueled by seeing it all fit together, we decided to tell the WaterColorBot to do some painting. Windell loaded up an example sketch in Inkscape and, with only a minute to calibrate the stylus height, we were drawing!

wcb-surface 7

The software running on the Surface Pro is called FreshPaint and we chose a simple marker tool. In the video, you’ll hear a laughter break where the Surface picked up the floating toolbar in the app and dragged it around the screen.

Given a little time, we could have taught the WaterColorBot to change brushes and colors in FreshPaint, but our goals for the day were met. The light weight and low friction of the Surface stylus is perfectly matched for use on the WaterColorBot. A custom fitted spoilboard means the Surface will always be at the exact same place on the X/Y plane, greatly simplifying future software development. Next project: Teaching the robot how to see!

wcb-surface 8
(Full disclosure: My day job is Systems Operations with Yammer, a Microsoft company. This project and use of the Surface Pro 2 is not affiliated with Microsoft in any way nor did they influence the project with sponsorship or exercise any editorial control. If they had, I’d try to talk them into contributing a Surface Pro 3! “Surface” is a trademark of Microsoft Corporation.)