S13: 2D Plotter - Revision history

Preet: /* Project Source Code */

2013-05-23T21:01:44Z

‎Project Source Code

Matthias s13: /* Software Design */

2013-05-23T09:58:57Z

‎Software Design

Matthias s13: /* Software Design */

2013-05-23T09:56:24Z

‎Software Design

Matthias s13: /* Software Design */

2013-05-23T09:55:37Z

‎Software Design

Matthias s13: /* Software Design */

2013-05-23T09:46:59Z

‎Software Design

Matthias s13: /* Software Design */

2013-05-23T09:44:09Z

‎Software Design

Matthias s13: /* Software Design */

2013-05-23T09:43:02Z

‎Software Design

Matthias s13: /* Hardware Interface */

2013-05-23T09:26:50Z

‎Hardware Interface

Matthias s13: /* Software Design */

2013-05-23T09:07:20Z

‎Software Design

Matthias s13: /* Software Design */

2013-05-23T09:05:23Z

‎Software Design

@@ Line 555: / Line 555: @@
 === Project Source Code ===
-Send me your zipped source code and I will upload this to SourceForge and link it for you.
+*  [https://sourceforge.net/projects/sjsus13/files/ Project source code is available at SourceForge]
 == References ==

@@ Line 505: / Line 505: @@
 The stepCount in this formula is the total number of steps as the print head is moved, for example, button_1 to button_2.
 <br />
 === Implementation ===

@@ Line 501: / Line 501: @@
 The gotoOrigin function is different from regular print functions because the print duration ( the third value passed to the <i>motor_control()</i> function can exceed the maximum possible number of steps since the limit switches will indicated to the plotter that the print head has reached the origin. For any other vector, the duration needs to be determined based on the length of the vector and the resolution (step width) of the motors, a value that can be obtained using the formula
 <pre>
-<i>resulution = distance / stepCount</i>
+resulution = distance / stepCount
 </pre>
-, where stepCount is the total number of steps as the print head is moved, for example, button_1 to button_2.
+The stepCount in this formula is the total number of steps as the print head is moved, for example, button_1 to button_2.
 <br />

@@ Line 497: / Line 497: @@
      motor_control(0,1,20,speed_y);
+}
-</pre><br />
+</pre>
 === Implementation ===

@@ Line 405: / Line 405: @@
 === Software Design ===
 The current printer driver consists of the printerTask(), which is scheduled in the main function. The function of this task is to listen to a button event to run a test program. All the task-related functions are kept in a dedicated printer library, which consists of the <i>printer.hpp</i> header file and the code library <i>printer.cpp</i>.<br />
@@ Line 424: / Line 425: @@
 speed_y = 6;
 speed_x = 2;
-</pre><br />
+</pre>
 The GPIO settings are as follows:<br />
@@ Line 441: / Line 442: @@
 LPC_GPIO1->FIODIR &=  ~(1 << 31);
 LPC_GPIO2->FIODIR0 = 0x00; // Set Buttons as Input
-</pre><br />
+</pre>
@@ Line 482: / Line 483: @@
    vTaskDelay(speed);
+}
-</pre><br />
+</pre>

@@ Line 405: / Line 405: @@
 === Software Design ===
 The current printer driver consists of the printerTask(), which is scheduled in the main function. The function of this task is to listen to a button event to run a test program. All the task-related functions are kept in a dedicated printer library, which consists of the <i>printer.hpp</i> header file and the code library <i>printer.cpp</i>.
 '''printer.hpp'''
@@ Line 411: / Line 411: @@
 bool motor_init();
 bool motor_control(int motor, bool direction, int duration, int speed);
 void setproperinputoutputs();
 void gotoorigin();
@@ Line 420: / Line 418: @@
 </pre>
+The <i>motor_init()</i> function configures the GPIO pins and sets the speed for the motors that move the print head horizontaly and vertically. Motor torque is inversely related to the motor speed. Since the horizontal motor belt is very tight, the motor speed has to be lowered to provide sufficient torque to be able to pull the belt. Therefore, the speed settings for the two motors are
-software design for this project only had one task. This task had to listen to 4 customized push down buttons that limit the movement of the motors and 8 buttons on the board itself for debugging purposes while using 5 lines to drive the decoder. The decoder circuit is responsible for controlling all three stepper motors for the project.
+'''Print Speed Settings'''
-At boot up, the head device will simply stay at it's current location, where ever it may be on the board. Once our "HELLO" code runs, the project will move the motors to the bottom left edge of the platform. Once the buttons are touched via the rails, this will tell the software that it's at the origin. The code is hardcoded to say hello. But the real magic happens in the decoder.
+The GPIO settings are as follows:
-The decoder circuit is really simple. It counts from 0 to 3 to control the Y-axis rail, from 4 to 7 to control the X-axis, and from 8 to 11 to control the pen. It also has an enable signal to make sure none of motors are active. The software simply counts to move everything. The only huge limitation is the fact that the design can only move one motor at a time. This will be repaired with a shifting type of circuit.
+'''GPIO Settings'''
 === Implementation ===

@@ Line 271: / Line 271: @@
 <div style="text-align: center;">'''Illustration 10:''' Inside View of the Plotter </div><br />
-The L298N can control a 4-wire bipolar stepper motor using a 4-bit binary input. The required sequence is 4’b0001, 4’b0010’ 4’b0100’ and 4’b1000 for clockwise operation. Reversing the inputs will produce a counter-clockwise rotation. An input of 4’b1111 or 4’b0000 will not affect the current position of the stepper motor. Therefore, it is possible to control up to four motors with a 4 of 16 decoder such as a 74LS154. We are currently using a 4-of-16 decoder and three stepper motor controllers to test the hardware performance with the z-axis motor of the 3D printer in mind. However, the current hardware only does need 2 motors.<br />
+The L298N can control a 4-wire bipolar stepper motor using a 4-bit binary input. It is possible to control up to four motors with a 4 of 16 decoder such as a 74LS154. We are currently using a 4-to-16 decoder to control the three motors used for the plotter.<br />
 ==== Electronic Design ====