#include <math.h>
#include <stdlib.h>
#include <string.h>
#include "hal.h"
#include "nuts_bolts.h"
#include "protocol.h"
#include "machine_limits.h"
#include "state_machine.h"
#include "motion_control.h"
#include "tool_change.h"
#include "kinematics.h"

Functions
bool	mc_line (float target, plan_line_data_t pl_data)

void	mc_arc (float target, plan_line_data_t pl_data, float position, float offset, float radius, plane_t plane, int32_t turns)

void	mc_cubic_b_spline (float target, plan_line_data_t pl_data, float position, float first, float *second)

void	mc_canned_drill (motion_mode_t motion, float target, plan_line_data_t pl_data, float position, plane_t plane, uint32_t repeats, gc_canned_t canned)

void	mc_thread (plan_line_data_t pl_data, float position, gc_thread_data *thread, bool feed_hold_disabled)

status_code_t	mc_jog_execute (plan_line_data_t pl_data, parser_block_t gc_block, float *position)

void	mc_dwell (float seconds)

status_code_t	mc_homing_cycle (axes_signals_t cycle)

gc_probe_t	mc_probe_cycle (float target, plan_line_data_t pl_data, gc_parser_flags_t parser_flags)

bool	mc_parking_motion (float parking_target, plan_line_data_t pl_data)

void	mc_override_ctrl_update (gc_override_flags_t override_state)

ISR_CODE void ISR_FUNC()	mc_reset (void)

Function Documentation

◆ mc_arc()

void mc_arc	(	float *	target,
		plan_line_data_t *	pl_data,
		float *	position,
		float *	offset,
		float	radius,
		plane_t	plane,
		int32_t	turns
	)

◆ mc_canned_drill()

void mc_canned_drill	(	motion_mode_t	motion,
		float *	target,
		plan_line_data_t *	pl_data,
		float *	position,
		plane_t	plane,
		uint32_t	repeats,
		gc_canned_t *	canned
	)

◆ mc_cubic_b_spline()

void mc_cubic_b_spline	(	float *	target,
		plan_line_data_t *	pl_data,
		float *	position,
		float *	first,
		float *	second
	)

The algorithm for computing the step is loosely based on the one in Kig (See https://sources.debian.net/src/kig/4:15.08.3-1/misc/kigpainter.cpp/#L759) However, we do not use the stack.

The algorithm goes as it follows: the parameters t runs from 0.0 to 1.0 describing the curve, which is evaluated by eval_bezier(). At each iteration we have to choose a step, i.e., the increment of the t variable. By default the step of the previous iteration is taken, and then it is enlarged or reduced depending on how straight the curve locally is. The step is always clamped between MIN_STEP/2 and 2*MAX_STEP. MAX_STEP is taken at the first iteration.

For some t, the step value is considered acceptable if the curve in the interval [t, t+step] is sufficiently straight, i.e., sufficiently close to linear interpolation. In practice the following test is performed: the distance between eval_bezier(..., t+step/2) is evaluated and compared with 0.5*(eval_bezier(..., t)+eval_bezier(..., t+step)). If it is smaller than SIGMA, then the step value is considered acceptable, otherwise it is not. The code seeks to find the larger step value which is considered acceptable.

At every iteration the recorded step value is considered and then iteratively halved until it becomes acceptable. If it was already acceptable in the beginning (i.e., no halving were done), then maybe it was necessary to enlarge it; then it is iteratively doubled while it remains acceptable. The last acceptable value found is taken, provided that it is between MIN_STEP and MAX_STEP and does not bring t over 1.0.

Caveat: this algorithm is not perfect, since it can happen that a step is considered acceptable even when the curve is not linear at all in the interval [t, t+step] (but its mid point coincides "by chance" with the midpoint according to the parametrization). This kind of glitches can be eliminated with proper first derivative estimates; however, given the improbability of such configurations, the mitigation offered by MIN_STEP and the small computational power available on Arduino, I think it is not wise to implement it.

◆ mc_dwell()

void mc_dwell ( float seconds )

◆ mc_homing_cycle()

status_code_t mc_homing_cycle ( axes_signals_t cycle )

◆ mc_jog_execute()

status_code_t mc_jog_execute	(	plan_line_data_t *	pl_data,
		parser_block_t *	gc_block,
		float *	position
	)

◆ mc_line()

bool mc_line	(	float *	target,
		plan_line_data_t *	pl_data
	)

◆ mc_override_ctrl_update()

void mc_override_ctrl_update ( gc_override_flags_t override_state )

◆ mc_parking_motion()

bool mc_parking_motion	(	float *	parking_target,
		plan_line_data_t *	pl_data
	)

◆ mc_probe_cycle()

gc_probe_t mc_probe_cycle	(	float *	target,
		plan_line_data_t *	pl_data,
		gc_parser_flags_t	parser_flags
	)

◆ mc_reset()

ISR_CODE void ISR_FUNC() mc_reset ( void )

◆ mc_thread()

void mc_thread	(	plan_line_data_t *	pl_data,
		float *	position,
		gc_thread_data *	thread,
		bool	feed_hold_disabled
	)

Functions