A clock which plots time. Designed with makeability in a fablab/makerspace/hackerspace in mind.
- Laser cutter or 3D printer
- 1 Arduino
- 3 servos
- 1 dry wipe pen
- M3 nuts, bolts, thread tap
Update to V1.01:
Added calibration documentation and routine to arduino code
See the instruction tab above for building instructions
https://github.com/9a/plotclock (old, not maintained!)
I am not connected with any kits you are able to Purchase online
Update 08/15: You might want to take a look at http://www.thingiverse.com/thing:931498/#instructions for a more detailed documentation
Update 10/15: You should also take a look at http://www.instructables.com/id/Plot-Clock-for-dummies/?ALLSTEPS Thanks to Kjetil Egeland!
Materials I used:
- Arduino uno
- Tower Pro 9g servos (those cheap ones from ebay)
- WB SL DRYWIPE MARKER, bullet tip
- A little custom servo adapter, you will find shields or servo-arduinos that can also be used. You can also just use jumper cables: 5V to crimson servo wire, GND to brown or black servo wire and the arduino servopins connected to the yellow or orange servo wire
(for version 1.01!)
Lasercut plotclock_beta1. Pdf from 3mm substance or 3D print plotclock_SUP7. skp
- The black regions in the pdf on the servo arms should be used to engrave some material away, hence the servohorns settle in
- use http://www.thingiverse.com/thing:250204 for single STL files if you 3D print the clock (Thanks corben33!)
3D print swee.stl or reuse some other part for the sweeper
Tap on 2.5Millimeter holes
Construct arms with M3 screws, gently adjust the counternuts so that the joints under the screw heads just have enough play for smooth motion (see joint picture).
Load Arduino sketch plotclock_V1, see code comments
Add Some Kind of cloth
Attach servos to electronic pin 2, 3 and 4, based on arduino sketch, test them without anything connected by plugging in the arduino (the photos show it being connected to 1, 2 and 3, which is not optimal since 1 is also the TX pin, so during arduino startup the lifting servo jumps around)
Put everything together
- You might have to redrill the holes which are used for securing the servos, since some servo screws are a tight fit.
Acrylic is brittle and readily breaks wen the mounting holes are to small. Only push the servo arms on their hubs, do not secure them with screws! For initial calibration don't mount the resting clip for the wiper (threat of collision with the pencil). Glue or screw the servo arms into the parts.
When attaching the servo arms, make sure they can turn enough to reach every point on the drawing surface by turning them
Power the arduino, it ought to start a calibration cycle where each second the position of both servos varies by rotating exactly 90 degrees (see last image in gallery)
Change the SERVOFAKTOR, SERVOLEFTNULL and SERVORIGHTNULL values until everything matches up (see code for more information)
- Attach the pencil and the sweeper holder just after analyzing everything else
This description is a bit of a WIP, so comment if you have any queries!