Fix and combine JD condition

This commit is contained in:
Scott Lahteine 2020-05-04 19:01:54 -05:00
parent d571a4d389
commit c55475e8e7

View file

@ -2306,87 +2306,87 @@ bool Planner::_populate_block(block_t * const block, bool split_move,
vmax_junction_sqr = junction_acceleration * junction_deviation_mm * sin_theta_d2 / (1.0f - sin_theta_d2);
if (block->millimeters < 1) {
const float neg = junction_cos_theta < 0 ? -1 : 1,
t = neg * junction_cos_theta;
// For small moves with >135° junction (octagon) find speed for approximate arc
if (block->millimeters < 1 && junction_cos_theta < -0.7071067812f) {
// If angle is greater than 135 degrees (octagon), find speed for approximate arc
if (t > 0.7071067812f) {
#if ENABLED(JD_USE_MATH_ACOS)
#if ENABLED(JD_USE_MATH_ACOS)
#error "TODO: Inline maths with the MCU / FPU."
#error "TODO: Inline maths with the MCU / FPU."
#elif ENABLED(JD_USE_LOOKUP_TABLE)
#elif ENABLED(JD_USE_LOOKUP_TABLE)
// Fast acos approximation (max. error +-0.01 rads)
// Based on LUT table and linear interpolation
// Fast acos approximation (max. error +-0.01 rads)
// Based on LUT table and linear interpolation
/**
* // Generate the JD Lookup Table
* constexpr float c = 1.00751317f; // Correction factor to center error around 0
* for (int i = 0; i < jd_lut_count - 1; ++i) {
* const float x0 = (sq(i) - 1) / sq(i),
* y0 = acos(x0) * (i ? c : 1),
* x1 = 0.5 * x0 + 0.5,
* y1 = acos(x1) * c;
* jd_lut_k[i] = (y0 - y1) / (x0 - x1);
* jd_lut_b[i] = (y1 * x0 - y0 * x1) / (x0 - x1);
* }
* jd_lut_k[jd_lut_count - 1] = jd_lut_b[jd_lut_count - 1] = 0;
*
* // Compute correction factor (Set c to 1.0f first!)
* float min = INFINITY, max = -min;
* for (float t = 0; t <= 1; t += 0.0003f) {
* const float e = acos(t) / approx(t);
* if (isfinite(e)) {
* if (e < min) min = e;
* if (e > max) max = e;
* }
* }
* fprintf(stderr, "%.9gf, ", (min + max) / 2);
*/
static constexpr int16_t jd_lut_count = 15;
static constexpr uint16_t jd_lut_tll = 1 << jd_lut_count;
static constexpr int16_t jd_lut_tll0 = __builtin_clz(jd_lut_tll) + 1; // i.e., 16 - jd_lut_count
static constexpr float jd_lut_k[jd_lut_count] PROGMEM = {
-1.03146219f, -1.30760407f, -1.75205469f, -2.41705418f, -3.37768555f,
-4.74888229f, -6.69648552f, -9.45659828f, -13.3640289f, -18.8927879f,
-26.7136307f, -37.7754059f, -53.4200745f, -75.5457306f, 0.0f };
static constexpr float jd_lut_b[jd_lut_count] PROGMEM = {
1.57079637f, 1.70886743f, 2.04220533f, 2.62408018f, 3.52467203f,
4.85301876f, 6.77019119f, 9.50873947f, 13.4009094f, 18.9188652f,
26.7320709f, 37.7884521f, 53.4292908f, 75.5522461f, 0.0f };
/**
* // Generate the JD Lookup Table
* constexpr float c = 1.00751317f; // Correction factor to center error around 0
* for (int i = 0; i < jd_lut_count - 1; ++i) {
* const float x0 = (sq(i) - 1) / sq(i),
* y0 = acos(x0) * (i ? c : 1),
* x1 = 0.5 * x0 + 0.5,
* y1 = acos(x1) * c;
* jd_lut_k[i] = (y0 - y1) / (x0 - x1);
* jd_lut_b[i] = (y1 * x0 - y0 * x1) / (x0 - x1);
* }
* jd_lut_k[jd_lut_count - 1] = jd_lut_b[jd_lut_count - 1] = 0;
*
* // Compute correction factor (Set c to 1.0f first!)
* float min = INFINITY, max = -min;
* for (float t = 0; t <= 1; t += 0.0003f) {
* const float e = acos(t) / approx(t);
* if (isfinite(e)) {
* if (e < min) min = e;
* if (e > max) max = e;
* }
* }
* fprintf(stderr, "%.9gf, ", (min + max) / 2);
*/
static constexpr int16_t jd_lut_count = 15;
static constexpr uint16_t jd_lut_tll = 1 << jd_lut_count;
static constexpr int16_t jd_lut_tll0 = __builtin_clz(jd_lut_tll) + 1; // i.e., 16 - jd_lut_count
static constexpr float jd_lut_k[jd_lut_count] PROGMEM = {
-1.03146219f, -1.30760407f, -1.75205469f, -2.41705418f, -3.37768555f,
-4.74888229f, -6.69648552f, -9.45659828f, -13.3640289f, -18.8927879f,
-26.7136307f, -37.7754059f, -53.4200745f, -75.5457306f, 0.0f };
static constexpr float jd_lut_b[jd_lut_count] PROGMEM = {
1.57079637f, 1.70886743f, 2.04220533f, 2.62408018f, 3.52467203f,
4.85301876f, 6.77019119f, 9.50873947f, 13.4009094f, 18.9188652f,
26.7320709f, 37.7884521f, 53.4292908f, 75.5522461f, 0.0f };
const float neg = junction_cos_theta < 0 ? -1 : 1,
t = neg * junction_cos_theta;
const int16_t idx = (t == 0.0f) ? 0 : __builtin_clz(uint16_t((1.0f - t) * jd_lut_tll)) - jd_lut_tll0;
const int16_t idx = (t == 0.0f) ? 0 : __builtin_clz(uint16_t((1.0f - t) * jd_lut_tll)) - jd_lut_tll0;
float junction_theta = t * pgm_read_float(&jd_lut_k[idx]) + pgm_read_float(&jd_lut_b[idx]);
if (neg > 0) junction_theta = RADIANS(180) - junction_theta;
float junction_theta = t * pgm_read_float(&jd_lut_k[idx]) + pgm_read_float(&jd_lut_b[idx]);
if (neg > 0) junction_theta = RADIANS(180) - junction_theta; // acos(-t)
#else
#else
// Fast acos(-t) approximation (max. error +-0.033rad = 1.89°)
// Based on MinMax polynomial published by W. Randolph Franklin, see
// https://wrf.ecse.rpi.edu/Research/Short_Notes/arcsin/onlyelem.html
// acos( t) = pi / 2 - asin(x)
// acos(-t) = pi - acos(t) ... pi / 2 + asin(x)
// Fast acos(-t) approximation (max. error +-0.033rad = 1.89°)
// Based on MinMax polynomial published by W. Randolph Franklin, see
// https://wrf.ecse.rpi.edu/Research/Short_Notes/arcsin/onlyelem.html
// acos( t) = pi / 2 - asin(x)
// acos(-t) = pi - acos(t) ... pi / 2 + asin(x)
const float asinx = 0.032843707f
+ t * (-1.451838349f
+ t * ( 29.66153956f
+ t * (-131.1123477f
+ t * ( 262.8130562f
+ t * (-242.7199627f
+ t * ( 84.31466202f ) ))))),
junction_theta = RADIANS(90) + neg * asinx; // acos(-t)
const float neg = junction_cos_theta < 0 ? -1 : 1,
t = neg * junction_cos_theta,
asinx = 0.032843707f
+ t * (-1.451838349f
+ t * ( 29.66153956f
+ t * (-131.1123477f
+ t * ( 262.8130562f
+ t * (-242.7199627f
+ t * ( 84.31466202f ) ))))),
junction_theta = RADIANS(90) + neg * asinx; // acos(-t)
// NOTE: junction_theta bottoms out at 0.033 which avoids divide by 0.
// NOTE: junction_theta bottoms out at 0.033 which avoids divide by 0.
#endif
#endif
const float limit_sqr = (block->millimeters * junction_acceleration) / junction_theta;
NOMORE(vmax_junction_sqr, limit_sqr);
}
const float limit_sqr = (block->millimeters * junction_acceleration) / junction_theta;
NOMORE(vmax_junction_sqr, limit_sqr);
}
}