ManuelW/grbl-LPC-CoreXY
1
0
Fork 0
Code Issues Pull Requests Releases 1 Wiki Activity

Commit history, logo license, full-arc fix.

Browse Source 
- Commit history added to repo, as an easier way for people to see view
the changes over time.

- Grbl logo copyright license added. All rights reserved with regards
to the Grbl logo.

- G2/3 full circles would sometime not execute. The problem was due to
numerical round-off of a trig calculation. Added a machine epsilon
define to help detect and correct for this problem. Tested and should
not effect general operation of arcs.
This commit is contained in:
Sonny Jeon
2015-03-29 11:35:16 -06:00
parent 234195e721
commit 4c20a2173f
15 changed files with 4289 additions and 8 deletions
Download Patch File Download Diff File Expand all files Collapse all files

14
grbl/config.h
View File

@ -294,6 +294,16 @@
// bogged down by too many trig calculations.
#define N_ARC_CORRECTION 12 // Integer (1-255)
// The arc G2/3 g-code standard is problematic by definition. Radius-based arcs have horrible numerical
// errors when arc at semi-circles(pi) or full-circles(2*pi). Offset-based arcs are much more accurate
// but still have a problem when arcs are full-circles (2*pi). This define accounts for the floating
// point issues when offset-based arcs are commanded as full circles, but get interpreted as extremely
// small arcs with around machine epsilon (1.2e-7rad) due to numerical round-off and precision issues.
// This define value sets the machine epsilon cutoff to determine if the arc is a full-circle or not.
// NOTE: Be very careful when adjusting this value. It should always be greater than 1.2e-7 but not too
// much greater than this. The default setting should capture most, if not all, full arc error situations.
#define ARC_ANGULAR_TRAVEL_EPSILON 5E-7 // Float (radians)
// Time delay increments performed during a dwell. The default value is set at 50ms, which provides
// a maximum time delay of roughly 55 minutes, more than enough for most any application. Increasing
// this delay will increase the maximum dwell time linearly, but also reduces the responsiveness of
@ -369,9 +379,9 @@
// Force Grbl to check the state of the hard limit switches when the processor detects a pin
// change inside the hard limit ISR routine. By default, Grbl will trigger the hard limits
// alarm upon any pin change, since bouncing switches can cause a state check like this to
// misread the pin. When hard limits are triggers, this should be 100% reliable, which is the
// misread the pin. When hard limits are triggered, they should be 100% reliable, which is the
// reason that this option is disabled by default. Only if your system/electronics can guarantee
// the pins don't bounce, we recommend enabling this option. If so, this will help prevent
// that the switches don't bounce, we recommend enabling this option. This will help prevent
// triggering a hard limit when the machine disengages from the switch.
// NOTE: This option has no effect if SOFTWARE_DEBOUNCE is enabled.
// #define HARD_LIMIT_FORCE_STATE_CHECK // Default disabled. Uncomment to enable.

2
grbl/grbl.h
View File

@ -23,7 +23,7 @@
// Grbl versioning system
#define GRBL_VERSION "0.9i"
#define GRBL_VERSION_BUILD "20150327"
#define GRBL_VERSION_BUILD "20150329"
// Define standard libraries used by Grbl.
#include <avr/io.h>

4
grbl/motion_control.c
View File

@ -100,9 +100,9 @@
// CCW angle between position and target from circle center. Only one atan2() trig computation required.
float angular_travel = atan2(r_axis0*rt_axis1-r_axis1*rt_axis0, r_axis0*rt_axis0+r_axis1*rt_axis1);
if (is_clockwise_arc) { // Correct atan2 output per direction
if (angular_travel >= 0) { angular_travel -= 2*M_PI; }
if (angular_travel >= -ARC_ANGULAR_TRAVEL_EPSILON) { angular_travel -= 2*M_PI; }
} else {
if (angular_travel <= 0) { angular_travel += 2*M_PI; }
if (angular_travel <= ARC_ANGULAR_TRAVEL_EPSILON) { angular_travel += 2*M_PI; }
}
// NOTE: Segment end points are on the arc, which can lead to the arc diameter being smaller by up to