The best part about SaaS

Do NOT search for "sass" on Flickr

Do NOT search for “sass” on Flickr

I’ve mentioned that I’ve got this software-as-service website. 1 2  Today, while dealing with a tech support problem, I realized what I love most about this type of business.

But, first, the tech problem.  A user e-mails me saying that he can’t log into the site from his iPhone (running iOS6) any more.  First, I try his login/password to confirm they work.  They do.  I have him try refreshing the page – I’ve heard the new iOS sometimes causes weird caching problems.  He still can’t log in.  I try logging in from an iPhone 4 running iOS6 and an iPhone 4S running iOS6.  No good.  I get him to confirm he’s clicking “remember me” when he logs in.  Yes, he is.  I finally tell him I can’t explain what’s going on – I’ve tried to replicate his problem on another iPhone 4 running iOS6, just like his, and I can’t figure out what happened.

He e-mails me a little later to say that he figured out that his iPhone had been set to reject cookies, and thus, he was not able to log in.

Which brings me to the thing I love about my SaaS business.  When someone says the site doesn’t work, all I have to do is confirm that it works in some browser somewhere on the internet – and then I’m basically 99% sure the problem is on their end.  Now, I can help them troubleshoot a problem to a certain extent, but for the most part if my site works in any one browser, it should work anywhere.  I don’t have to worry about their operating system, software conflicts, and other nonsense like that.  Just get to the internet and the site should work.

  1. Photo courtesy of Sebastián Dario []
  2. Why a photo of a puppy?  Well, I tried searching for a photo that included the word “sass” on Flickr… and I now wish I had not done so. []

Why do DrawBots draw on walls?

A wall crawler - on the floor

A wall crawler – on the floor

A commenter named Ellison left a deceptively simple question on my first post in this DrawBot series.1

Ellison:  Why do it on a wall? Why not a drawing robot that draws on a large piece of paper on the ground? I think you’ll get better results from that.

I think there are a lot of good reasons reasons – some aesthetic, some technical, some practical – for having a DrawBot that draws on walls (or other vertical surfaces).

Aesthetically, I really like having a DrawBot that draws on vertical surfaces.  When placed in the room or an adjoining room, I can watch it scritch-scratching away at an enormous drawing.  In much the same way a snail’s meandering trail can be captivating, a DrawBot working out a TSP single-line-art drawing turns an apparently meaningless series of turns into a mass of scrawls that resolve into a work of art as soon as you take a step back. 2

Technically, the DrawBot is an exceedingly simple device.  You could build it out of little more than Arduino, a motorshield, two motors, string, a pen, and whatever you might have lying around.  Much of these pieces you could probably even scavenge for or salvage from other things.  In fact, only the Arduino and motorshield are things you wouldn’t be able to dumpster dive for.  The device works by moving the two motors in concert, such that by varying the length of string reeled in or out by a given motor is used to move the pen in an XY plane.  The one “ingredient” not listed in the preceding sentences is, of course, gravity.  If the point where the two strings meet at the pen did not hang essentially straight down, pulled constantly by gravity, the pen could go just about anywhere.  If you were to place a normally vertical standing DrawBot flat on the ground, the pen would no longer be pulled away from the two motors – and would just flop onto the drawing surface.  Now, you could add two more motors and more string and build a gondola that holds the pen vertically on a flat DrawBot surface while writing a lot more code…  However, I am doubtful you would get any more precision out of such a setup.  And, if you really require precision – an XY plotter might be more to your liking.  An XY plotter build would require lots of hardware (belts and metal rods or metal extrusions), more tools, and be big and heavy, and limited in the size of its drawing capabilities.  It would also be capable of really amazing speeds.  That’s a lot of extra materials, work, custom coding, and loss of drawing capacity for a dubious trade off in

As a matter of practicality, the simplicity of design and materials means this is an extremely cheap project.  An Arduino is only going to set you back about $30 and clones are as cheap as $15.  I picked up two of Adafruit’s motor shields on sale for $12 each, but they’re normally $20.  Screws and/or bolts, beaded cord or wire or fishing line, a big piece of wood or mounting things directly to a wall, 3D printed spools or just leftover spools from thread, a 3D printed gondola or a lasercut gondola or even a big red binder clip.3  Seriously, if you’ve got about $35 and some free time, you’re basically half way to building an awesome fun robot that can make arbitrarily large drawings.  If you’re willing to buy all the materials, it probably won’t cost you more than $150.

I’ll say it again – a Polargraph DrawBot is a quick, cheap, easy, entertaining, and useful robotics project – especially for beginners.  Outside of my 3D printers, this was easily the most rewarding DIY project I’ve ever attempted.  The results are astoundingly disproportionately awesome to the amount of time, energy, skill, and money used to achieve them.

Seriously, what are you waiting for?!  Go order a Polargraph kit from Sandy Noble45 or source the parts from Adafruit6 .7  Or, if you’re going to scavenge and/or source some parts, check out my Polargraph DrawBot parts/shopping lists.

Posts in the DrawBot Adventure Series
  1. Wanna make a DrawBot?
  2. DrawBot, the Adventure Begins
  3. DrawBots for the slow learner
  4. DrawBot - Parts Ordered!!!
  5. DrawBot - The Breakdown
  6. DrawBot - Parts Shipped!!!
  7. DrawBot - The Plan!
  8. DrawBot - The Hacks
  9. DrawBot - Giant Unicorn?
  10. DrawBot - The Delivery, Part II
  11. DrawBot – The Delivery, Part III
  12. DrawBot – The Assembly, Part I
  13. DrawBot – The Software, Part I (and an existential conversation)
  14. DrawBot – The Delivery, Part IV
  15. DrawBot – The Assembly, Part II
  16. DrawBot – The Assembly, Part III
  17. DrawBot – Design Considerations
  18. DrawBot – Halp!!! No - seriously, a little help?
  19. DrawBot – The Face Palm
  20. DrawBot – The Delivery, Part V
  21. DrawBot – The Silver Lining of Failure
  22. DrawBot – The Delivery, Part VI
  23. DrawBot – The Assembly, Part V
  24. DrawBot – The Assembly, Part VI
  25. DrawBot – Printed Parts
  26. DrawBot – The Assembly, Part VII
  27. DrawBot – The Operation, Part I
  28. DrawBot – The Assembly, Part VIII
  29. DrawBot – The Breakdown, Part II
  30. DrawBot – Printing!
  31. DrawBot – Printing, Part II
  32. DrawBot – Calibration
  33. DrawBot – Pen Selection
  34. DrawBot – How to Recover from a Stalled Print!
  35. DrawBot – Drawing Success(ish)!!!
  36. DrawBot – Pen Selection, Part II
  37. DrawBot – Onwards and Upwards!
  38. Restarting a Stalled DrawBot Drawing
  39. TSP FTW!
  40. Speedier DrawBot Drawings
  41. Two new DrawBot links! And an update!
  42. Excellent DrawBot Slides
  43. Another Drawing Robot!!!
  44. DrawBot Practice Tip: A Watched Pot
  45. The biggest inkjet printer ever
  46. Why do DrawBots draw on walls?
  47. All New Polargraph on the way!!!
  48. Ideas for improving my DrawBot
  49. DrawBot Aesthetic Re-Design Ideas
  50. The Eagle Has Landed
  51. Every Body Needs a Skull
  52. I think I know what I want to draw next...
  53. Overengineered Spools
  54. Overengineered Stepper Motor Mounts, Filament Guides
  55. Overengineered Bolt Endcaps, Case Holder
  56. Sourcing DrawBot Parts
  57. DrawBot - A Tour!
  58. Arduino Powered Drawing Robot Poll
  59. Building an Arduino Drawing Robot - On The Cheap
  60. Unidentified Foam Object
  61. Arduino Powered Drawing Robot - Take 2 (Or 3)
  62. DrawBot, now ACTUALLY wall mounted!
  63. A Study of Drawing Robot Pen Holders and Design Considerations
  64. Drawing Robot Pen Holders, Calligraphy Pens, and Thought Experiments
  65. Ideal Qualities in a Drawing Robot Pen Holder
  66. Enough talk! Finally a pen holder!
  67. DrawBot Pen Holder Post Mortem
  68. To Maker Faire!!!
  69. Skipping! How could I forget the skipping?!
  70. Drawing Robot Penmanship
  71. PlotterBot at Maker Faire Bay Area 2013!
  72. - a new site dedicated to drawing robots
  1. Photo courtesy of The Kozy Shack []
  2. And, I wonder – if you could map all snails in the world at the same time, could they be working in concert on an enormous message?  Perhaps something along the lines of “So long, and thanks for all the fish”? []
  3. I just love that Polargraph video by Sandy Noble.  To see binder clip in action, skip ahead to 0:27. []
  4. Whose open source work I use for my own DrawBot []
  5. The next time he’s in stock, you better pull the trigger – he runs out of stock SUPER fast []
  6. Where I bought most of my parts! []
  7. And, why not tell them I sent you too? []