like a brake cable on a bicycle.
Since the goal is to put down a fine layer
of plastic, ether the hot end/extruder must be
moved or the object itself must be moved as
the layer is put down. In reality, this is often a
combination of both. This is achieved with at
least one stepper motor on each of the X, Y,
and Z axes. Often a timing belt and pulley is
used in conjunction with the motor as
shown in Figure 4.
The stepper motors are maneuvered
with a controller much like the one shown in
Figure 5. This is a RAMPS board, and it and its
variants are very popular in the 3D printer
Sanguinololu is a low cost all-in-one electronics solution for
Reprap and other CNC devices. It features an onboard Sanguino
clone using the ATMEGA644P, though an ATMEGA1284 is easily
dropped in. Its four axes are powered by Pololu pin compatible
The board features a developer-friendly expansion port
supporting I2C, SPI, and UART, as well as a few ADC pins. All 14
expansion pins can be used as GPIO, as well.
The board is designed to be flexible in the user's power
source availability, allowing for an ATX power supply to power the
board, or the user can choose to install a voltage regulator for
60 SERVO 05.2013
use with any power supply 7V-30V.
Teensylu is based on Sanguinololu. The ATMEGA644P has
been replaced with an Atmel AT90USB1286 MCU. This
microcontroller has on-chip USB, removing the need for the FTDI
USB UART. All of the through hole resistors and capacitors have
been replaced with 0805 SMT components (as of Ver 0.1).
Like the Sanguinololu, the Teensylu has expansion headers
supporting I2C, SPI, UART, and ADC pins. All extra I/O ports of
the AT90USB have been broken out to headers for prototyping.
Courtesy of Wikipedia.org