Skip to content

sdustinh/plotclock

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

9 Commits
 
 
 
 
 
 
 
 
 
 

Repository files navigation

plotclock

plotclock

a clock that plots time

What you need

  • Lasercutter or 3D Printer

  • one Arduino (e.g. uno)

  • three RC-Servos Mini (e.g. Tower Pro 9g)

  • one whiteboard marker, dry eerasable (e.g. WB SL DRYWIPE MARKER)

  • Screws, nuts, washers M3 and a tap for cutting M3.

Assembly

(see illustrations at http://wiki.fablab-nuernberg.de/w/Ding:Plotclock#Zusammenbau )

Use the plotclock PDF file for lasercutting acrylic 3mm or

use the plotclock SKP file for alternative 3D-Parts.

The blackend area in the PDF are to be engraved, not cut. This improves grip for the servo hubs.

swee.stl (a wiper) for 3D printing the cap of the pen with the eraser.

This can also be constructed from cylindrical parts.

Some holes are 2.5mm only, cut M3 threads there.

Assemble the servo arms. Gently adjust the counternuts so that the joints

under the screw heads just have enough play for smooth movement.

Load the Arduino software (check the comments).

http://playground.arduino.cc/Code/time is used as a clock library.

Glue a piece of cloth to the wiper with doublesided tape.

Connect the servo signal lines to pins 2, 3, and 4 of the Arduino board.

Employ a small daughterboard for powering the servos, if needed.

Test drive the software without mounting servo arms.

Complete the assembly as shown in the illustrations. Widen the holes for

servo mounting if needed. Acrylic is brittle and easily breaks wen the mounting holes are to small. Only push the servo arms onto their hubs, don't secure them with screws! For initial calibration do not mount the resting clip for the wiper (danger of collision with the pen). Glue or screw the servo arms to the acrylic parts.

When you connect the Arduino, it will first run a calibration routine. The

arms move between 2 positions, which correspond to exaxtly 90° servo movement.

The calibration values SERVOFAKTOR, SERVOLEFTNULL, and SERVORIGHTNULL allow to adjust the actual positions to the ideal ones. Please take care that the servos allow sufficient range and do not hit their internal end stops. If needed move the servo arms on the hubs.

Finally mount the pen and wiper rest. Uncomment the #define CALIBRATION in

the Arduino scetch or remove the line.

Adjust the current time in the Arduino program and you are ready to go.

--

this actually is my first git project, so merging, forks etc. is still new to me and could take some time

About

plotclock

Resources

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published