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Spark Creativity? Don’t get out of the box. Design your own box and think from within!

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For years I have dismantled old printers, clocks, radio’s, disk drives, got all the screws out and sorted them in neat little boxes, taking the plastic gears, bearings, etc.. and storing them all separately. This all resulted in a workshop with a large amount of boxes, drawers, cabinets, all filled with a wealth of electronic parts, gears, motors. Strangely enough, coming to think of it, I have hardly ever used most of these parts later on. They always -just-don’t-fit-entirely- but ‘will do as placeholder for now’.

I’m currently in a luxury position that the projects I build are being paid by other people. In order to save time, I order parts from online suppliers and hardly touch what’s left on my shelves. It is quite risky to use salvaged parts in production, you can never be sure that you can order replacement parts within a day. (Instead you have to go out on a Ebay-hunt for that one specific type of plotter you remember taking these nice gears out)

As engineer your problem solving space is mostly defined by performance on the one hand and time + money on the other hand. Technically and creatively, virtually no boundaries apply. Just get the best parts you can find for sum X and build your machine in time Y. Interesting observation is that these constraints do not go well with hobby work (which most of the time is lacking both time and money) Perhaps a good definition for distinction between hobby and professional: lack of deadlines?

Recently I started giving physical programming courses in a Creative Technology bachelor track. The assignments that spark most creativity are the assignments with on the one hand a clear goal (make something that does this or that) and on the other hand a severe limitation (but use only these parts). One nice example that yielded most creative solutions this year was designing a drawing application using Processing/Arduino. The only input that could be used for this drawing application was one light-sensor (LDR) connected to the Arduino. No other inputs could be used. At first students were complaining. It could not be done. It was way to limited. What? was I really serious? There must have been a mistake in the assignment-description… and so on. After a while they accepted the challenge and were getting into it. I have never seen so many different outcomes of one (simple) assignment that work all differently. Not that they were all good or usable, but all solutions were different, working, creative and most important of all, fun. This assignment worked by far better than ‘make a nice animation using shapes and images’ - which leaves far more room for creativity (you would think so) … but does not spark imagination at all, apparently.

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Some time ago the spark of Personal Fabrication, or desktop fabrication caught me too. I need a 3D printer! Yes. I wants one! I started out searching and found most of the designs on internet that are neatly listed in Make Volume 21. Then I immediately hit the engineering boundaries of optimization. If you want a really useful machine, you need the fastest, most accurate and preferably not too expensive machine you can get. If you want CNC on your desktop, you need a system with backlash-free trapezoid spindle rods with ball-nuts. Nice linear sliders.. Oh. and standard Nema23 size stepper motors with micro step control. The easiest way is to order a kit, or get quality parts at a distributor - and after some 500$ to 1000$ you are the proud owner of a machine that will work for you..

I had three old dot-matrix printers lying around, which contains sliding rods, timing belts, stepper motors.. the basic ingredients for a Cartesian (XYZ) robot. My first approach was the classical one. Dismantle the printers, get the sliding rods out, salvage the bearings and stepper motor, start designing a base plate with nice brackets to mount the rods, get correct gears, get better stepper motors. I started reading on internet again. How somebody started out with printer parts, but regretted this, because he should have bought linear bearings from the start. How someone tried to use threaded m5 rod as spindle drive and failed miserably. No-one was even THINKING of using the crappy 50-step low resolution stepper motors that normally inhabit old StarLC-10’s, but immediately got themselves a decent set of some 400-step hybrid motors.

This project was going nowhere. I constantly found myself optimizing the design, trying to think of better parts, more accuracy, order good parts, order a kit. Perhaps abandon the printer junk completely. Hours on the project were mostly spent surfing internet, finding other CNC DIY designs on Instructables and maker’s blogs, browsing through kit distributors’ sites and manufacturers of spindle rods. All bouncing back and forth between the engineering criteria of performance vs. time and money.

Then I chose to severely limit my options. I was going to make a repstrap (3D fabricator) only from printer parts and salvaged computer Junk. No spindle rods, expensive bearings or high qualtiy stepper motors. All of a sudden the goals and the problem-solving space were very clear, and the project took off like a rocket.

The initial steps were simple. I took three printer head mechanisms and bolted them together to form a two-axis machine. I cut the printer-driver boards to leave only the stepper motor drivers, used the printer’s power supply and took out an Arduino board to control the steppers. Key ingredient here was that I choose to leave intact as much of the original mechanisms as possible, saving me from the tedious work of making high-precision bearing mounts etc.

The initial tests were very disappointing. The resolution of the print-head was way too crude, and, above all, the stepper motors were by far not powerful enough to reliably power the construction. I was on the verge of abandoning the project again. Then creativity really kicked in. Using the gears that were normally used for driving the paper rolls, I made an extra gear reduction in the printer-head mechanism. With the rods available from various clamp rolls, I made an axle synchronizing the movement left and right. The optical interruption switches were retrofitted as end-stop detectors.

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So.. the project is still underway. Conclusions till so far: store (and use) mechanisms, not just parts. Try to use as much as possible from original mechanisms as possible. This will save time, money - and also important - saves waist!

Conclusion number two: if you want to spark your creativity, severely restrict your problem-solving space. It sounds counter-intuitive, but it works!

Written by edwin

May 26th, 2010 at 8:53 pm

32×32 bit Pong

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Connecting everything with everything… Here a computer playing Pong with itself. The motorfaders from the Behringer BCF2000 can either used as user-input or taken over by the PC.

pong arduinocloseup

Check the processing example here

Written by edwin

March 11th, 2009 at 2:11 am

Back from Suzhou

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Last monday we traveled back from Suzhou. Unfortunately the robots have been delayed by the customs inspection, so we haven’t been able to continue working on them. Visiting the RoboCup 2008 has been a great experience, and I think it was certainly worth it to have 18 people working very committed on the completion of the robots. Next year in Austria we’ll be back :)

Written by edwin

July 22nd, 2008 at 8:00 pm

Posted in RoboCup 2008, Robotics, UT

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Suzhou update

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Days fly past here. We managed to get the second robot (twente-TUlip or just TUlip2) working right in time. Just minutes after we did its first complete test (standing still) the delft-TUlip (TUlip1) broke one of its optical encoders for hip angle measurement. So tomorrow we’ll have to use the TUlip2 robot for the goal-keeping contest! At the dutchrobotics website also a blog is being kept with a lot of pictures and movie clips.

Written by edwin

July 17th, 2008 at 8:59 pm

Posted in RoboCup 2008, Robotics, UT

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First day @ Suzhou

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Today started with a lot of work on our robots. To be honest, they were not completely working when they got here, and due to transport and other circumstances, besides the ’scheduled work’ there is a lot more to solve, repair, invent, design and build.

Besides the dealings with our own two robots, there is some time fortunately to walk around in the main Expo room. Over 300 contestants (all in all- I’m not sure I understood the Chinese guide correctly) divided over about 100 teams participating in various categories: humanoid soccer, fish soccer (polo?), rescue robots, home robots, etc.
In lot of the leagues, the technology is very similar over all contestants. Especially in the teen size humanoid league a lot of teams are participating with robots build with dynamixel servo’s. Most have directly build a robot with the robotis kit and use the camera as its main sensor. The camera is used for detecting whether the robot has fallen to the floor (dark/no image). Some use accelerometers for balancing and a few use a gyro for active balancing. When they use one, they use an RC gyro (normally used for model RC helicopters)

humanoid league, testing A clever solution comes from a German team which uses a Nokia telephone as brain. The bioloid servo system comes with a controller which has an optional bluetooth interface module. Unfortunately bluetooth is not allowed, so the team equipped the standard Bioloid controller with an RS232 coupling. Using the telephone’s camera and irda connection the telephone controls the robot. The telephone also comes with a 3d accelerometer which can be used for robot stabilization.

So, a lot of inspiring ideas, lots of people, and hopefully tomorrow a robot that can at least stand still :)

Written by edwin

July 15th, 2008 at 10:50 pm

Posted in RoboCup 2008, Robotics, UT

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Arrived in China for RoboCup 2008

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long bus trip to suzhouWith the team ‘Dutch Robotics‘ the three technical universities are going to participate in the RoboCup 2008. After a long flight we arrived in Shanghai today, and took an almost equally long coach-trip to Suzhou, where the contest is being held. We are hopping from air-conditioned bus to air-conditioned hotel room, which is just as well, because outside it is 35 degrees! First impression: China is big. China is Huge. There must be living So Many People in China. Wow.

Written by edwin

July 14th, 2008 at 2:01 pm

Posted in RoboCup 2008, Robotics, UT

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