Welcome! Log In Create A New Profile


Movement issues

Posted by JesperG 
Movement issues
May 03, 2013 08:56AM
Hi guys.

I'm struggling a bit setting up the software for my first RepRap here. Im on RAMPS 1.4 ontop of an Arduino MEGA using Sprinter firmware at the momemt (tried Marlin but gives me same problems). The problem I'm having is that the axis move waay too far. It seems that it is set to take too many steps pr mm. If i take the _AXIS_STEP_PER_UNIT down to around 10, it moves the correct distance, although quiet noisy. I also have to set the acceleration quiet low compared to default settings, otherwise the motors just vibrates.

Does anyone have any ideas what is going on here? I have been thinking that 1/16 microstepping might not be enabled, but I cant think of anyway to test that - and I have checked that the jumpers are connected, so unless I can put those on wrong, the motors should microstep. This really has me puzzled, I cant spot the error smiling smiley

Here is my firmware settings related to motors, movement and acceleration:

#define MOTHERBOARD 33

#define _AXIS_STEP_PER_UNIT {10, 10, 3200/1.25,700}

#define BAUDRATE 115200

#define X_ENABLE_ON 0
#define Y_ENABLE_ON 0
#define Z_ENABLE_ON 0
#define E_ENABLE_ON 0

const bool DISABLE_X = true;
const bool DISABLE_Y = true;
const bool DISABLE_Z = true;
const bool DISABLE_E = true;

const bool INVERT_X_DIR = true;
const bool INVERT_Y_DIR = true;
const bool INVERT_Z_DIR = true;
const bool INVERT_E_DIR = false;

const int NUM_AXIS = 4;
#define _MAX_FEEDRATE {400, 400, 2, 45}
#define _HOMING_FEEDRATE {1500,1500,120}
#define _AXIS_RELATIVE_MODES {false, false, false, false}

#define MAX_STEP_FREQUENCY 30000


#define _ACCELERATION 50
#define _MAX_XY_JERK 5.0
#define _MAX_Z_JERK 0.0
#define _MAX_E_JERK 5.0 // (mm/sec)
//#define _MAX_START_SPEED_UNITS_PER_SECOND {25.0,25.0,0.2,10.0}
#define _MAX_ACCELERATION_UNITS_PER_SQ_SECOND {500,500,50,500}

#define MINIMUM_PLANNER_SPEED 0.05 // (mm/sec)


#define _MIN_SEG_TIME 20000

#define SLOWDOWN

const int dropsegments=5;
Re: Movement issues
May 03, 2013 10:31AM
With the low steps/mm, I can get the motors to run smoothly around 5k feed rate, but at 500-ish which is a typical movement speed for printing, it seems that i get a lot of vibration. It seems though that i can fix this by turning down the current to the motors almost entirely on the Stepper Drivers.

Edited 1 time(s). Last edit at 05/03/2013 10:47AM by JesperG.
Sorry, only registered users may post in this forum.

Click here to login