RUG/Pennsylvania/State College/StepperMotorCamera

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Revision as of 16:18, 24 January 2014 by Aem28 (talk | contribs) (Editing the G-code)
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Overview

The Stepper motor camera system is meant to take pictures of an object while printing. A photo is automatically taken between each layer. The bed is homed for each photo, so that the distance between the object and the camera is always the same. Time-lapses can be created with this system.

Requirements

To use this system, you will need a printer flashed as if it had a dual-extruder (see the tutorial on how to flash a printer for more information: (RUG/Pennsylvania/State_College/Electronics/Flashing_tutorial). Also, make sure that the camera is fully charged and that its SD card is empty.

Editing the G-code

Several lines of G-code must be inserted when the layer changes, to home the bed and take a photo. A python script generates theses lines automatically (RUG/Pennsylvania/State_College/Software/Python_scripts#Camera). Once the g-code is modified, load it in Pronterface.

Installation and calibration

Several steps are required to prepare the camera:

  • Home the Y axis
  • Place the camera on the holder, and target the middle of the bed (where the object will be printed). A vice can help holding the system.
  • Plug the camera to the port of the second extruder
  • Turn on the camera
  • Move the blue finger close to the camera’s button
  • In Pronterface, enter the following commands:
    • T1: set the extruder to 1
    • M302: Enable cold extrusion
    • G1 F10: set the federate to 10 mm/min
    • G92 E0: set the current position of the finger to 0
    • G1 E*, where * is a number: increment the value of E by 0.1 to get closer to the button, then by 0.01 once you start pushing it. Increment E until a photo is taken (the camera’s screen will display the new photo for a few seconds)
    • G92 E0.1: change the reference for the extruder’s position (the position for which the button is pushed must be 0.1)
    • G1 E0: Move the finger to its initial position
    • T0: set the extruder to 0 (don’t forget this command, or else the default position for the camera will be reseted when the print starts, and you’l have to go through the previous steps again).

The photo system is now ready to print. Don’t move the camera or the blue finger during the print!

Recommandations

  • Don’t use the automatic mode of the camera (which will sometimes use the flash)
  • Make sure that the lightening of the room will remain constant during the print

Use the footage

Several softwares can be used to turn a series of photos into a video. At least 15 frames per second are required to get a fluid animation.