Hi, I need help efficiently reading in each row of a CSV when it is needed (all 12 columns) and saving it in an array called positions (as ‘long’ variable type, because I am saving large numbers with many decimal places and using +/- signs). I am going to be using matlab to generate some very complex motion profiles and I need to make a simple controller to follow those with a 3D printer. I am using a mega.
I’ve looked through a lot of forms and the sample code I’ve been able to find does not work the way i need it to, and I do not understand it enough to modify it to work. Here is the code structure template:
#include <AccelStepper.h>
#include <MultiStepper.h>
#include <SPI.h>
#include <SD.h>
File myFile;
const int chipSelect = 53;
long positions[12]; // Array for controlling steppers (I know that this library can only handle 10 stepper
//motors, I only have 4 stepper motors, but I have X_position, X_velocity, X_accel.... saved in the CSV)
AccelStepper stepper1(AccelStepper::FULL2WIRE, 3,4);
AccelStepper stepper2(AccelStepper::FULL2WIRE, 5,6);
AccelStepper stepper3(AccelStepper::FULL2WIRE, 7,8);
MultiStepper steppers;
void setup() {
Serial.begin(9600);
while (!Serial) {
; // wait for serial port to connect. Needed for native USB port only
}
if (!SD.begin(chipSelect)) {
Serial.println("initialization failed!");
return;
}
myFile = SD.open("book1.csv",FILE_READ);
// here i need to initialize the first row and all 12 of the columns of the CSV and save them to a matrix/arrray "positions"
// the numbers are for example 3045.5467 and they are signed too
// i was thinking of then storing the "position()" in the CSV we read the last number
// then close the CSV to save memory
positions[0] = 15000; // example X
positions[1] = 15000; // example Y
positions[2]= 15000; // example Z
// Configure each stepper
stepper1.setMaxSpeed(10000);
stepper2.setMaxSpeed(10000);
stepper3.setMaxSpeed(10000);
stepper1.setAcceleration(1000);
stepper2.setAcceleration(1000);
stepper3.setAcceleration(1000);
// Then give them to MultiStepper to manage
steppers.addStepper(stepper1);
steppers.addStepper(stepper2);
steppers.addStepper(stepper3);
}
void loop() {
steppers.moveTo(positions);
// while the stepper motors are moving I need to read in the next row of the CSV to replace positions[]... really need a function call here to read in the data to make the code cleaner
myFile = SD.open("book1.csv",FILE_READ);
//maybe at this point we can use the seek() based on the "position()" of the last read
//here i need to read in row 2 and all 12 of the columns of the CSV and save them to the matrix/arrray "positions"
// the numbers are for example 3045.5467 and they are signed too
// i was thinking of then storing the "position()" within the CSV we read the last number
// then close the CSV to save memory
//positions[0] = X_position is from CSV_column_1;
//positions[1] = Y_position is from CSV_column_2;
//positions[2]= Z_position is from CSV_column_3;
//positions[4] = X_velocity is from CSV_column_4;
//positions[7] = X_acceleration is from CSV_column_7; // and so on through Y, Z and the extruder
//positions[11] = CSV_column_12;
steppers.runSpeedToPosition(); // Blocks until all are in position
}
Further information/thoughts:
I can change the format of the CVS or change to a TXT or similarly common file type if it makes it easier. I also could actually make multiple CSV files since opening a single large file might use up all of my memory. I’m going to use Matlab to read in the GCODE and do a bunch of “fancy” controls computation for trajectory generation. Then I’m going to produce a file with every X,Y,Z: position, velocity, and acceleration setting for the entire print.
I can and have read/written to a TXT and CSV file with the arduino, so at least I know the wiring is right, but I need help with the software.
Lastly, does the “stepper1.setAcceleration(1000);” also set the deceleration limit?
Once I get this working I think I can produce some pretty nice improvements for 3D printer trajectory generation, but as a mechanical engineer my CS skills are lacking. Hopefully I’ll be able to work with this community or the Marlin community to convert what improvements I can provide with matlab code to the opensource arduino portfolio. This is a semester project for me which has limited time, but my professor PhD student was able to increase the average printer’s speed 2X without loosing any quality, (but that was ran a super powerful computer controller).
Much appreciated