From 3cd7659924830e5639737f92766f796c0b632f62 Mon Sep 17 00:00:00 2001 From: Scott Lahteine Date: Wed, 6 Dec 2017 23:57:57 -0600 Subject: [PATCH] Improved Core-compatible jerk code --- Marlin/src/module/planner.cpp | 39 ++++++++++------------------------- 1 file changed, 11 insertions(+), 28 deletions(-) diff --git a/Marlin/src/module/planner.cpp b/Marlin/src/module/planner.cpp index fc2dd2acd..0bdd3ef30 100644 --- a/Marlin/src/module/planner.cpp +++ b/Marlin/src/module/planner.cpp @@ -1090,10 +1090,13 @@ void Planner::_buffer_steps(const int32_t (&target)[XYZE], float fr_mm_s, const } #endif - // Calculate and limit speed in mm/sec for each axis + // Calculate and limit speed in mm/sec for each axis, calculate minimum acceleration ratio float current_speed[NUM_AXIS], speed_factor = 1.0; // factor <1 decreases speed + float max_stepper_speed = 0, min_axis_accel_ratio = 1; // ratio < 1 means acceleration ramp needed LOOP_XYZE(i) { const float cs = FABS((current_speed[i] = delta_mm[i] * inverse_secs)); + NOMORE(min_axis_accel_ratio, max_jerk[i] / cs); + NOLESS(max_stepper_speed, cs); #if ENABLED(DISTINCT_E_FACTORS) if (i == E_AXIS) i += extruder; #endif @@ -1138,6 +1141,9 @@ void Planner::_buffer_steps(const int32_t (&target)[XYZE], float fr_mm_s, const } #endif // XY_FREQUENCY_LIMIT + block->nominal_speed = max_stepper_speed; // (mm/sec) Always > 0 + block->nominal_rate = CEIL(block->step_event_count * inverse_secs); // (step/sec) Always > 0 + // Correct the speed if (speed_factor < 1.0) { LOOP_XYZE(i) current_speed[i] *= speed_factor; @@ -1145,6 +1151,9 @@ void Planner::_buffer_steps(const int32_t (&target)[XYZE], float fr_mm_s, const block->nominal_rate *= speed_factor; } + float safe_speed = block->nominal_speed * min_axis_accel_ratio; + static float previous_safe_speed; + // Compute and limit the acceleration rate for the trapezoid generator. const float steps_per_mm = block->step_event_count * inverse_millimeters; uint32_t accel; @@ -1246,32 +1255,6 @@ void Planner::_buffer_steps(const int32_t (&target)[XYZE], float fr_mm_s, const } #endif - /** - * Adapted from Průša MKS firmware - * https://github.com/prusa3d/Prusa-Firmware - * - * Start with a safe speed (from which the machine may halt to stop immediately). - */ - - // Exit speed limited by a jerk to full halt of a previous last segment - static float previous_safe_speed; - - float safe_speed = block->nominal_speed; - uint8_t limited = 0; - LOOP_XYZE(i) { - const float jerk = FABS(current_speed[i]), maxj = max_jerk[i]; - if (jerk > maxj) { - if (limited) { - const float mjerk = maxj * block->nominal_speed; - if (jerk * safe_speed > mjerk) safe_speed = mjerk / jerk; - } - else { - ++limited; - safe_speed = maxj; - } - } - } - if (moves_queued && !UNEAR_ZERO(previous_nominal_speed)) { // Estimate a maximum velocity allowed at a joint of two successive segments. // If this maximum velocity allowed is lower than the minimum of the entry / exit safe velocities, @@ -1283,7 +1266,7 @@ void Planner::_buffer_steps(const int32_t (&target)[XYZE], float fr_mm_s, const // Factor to multiply the previous / current nominal velocities to get componentwise limited velocities. float v_factor = 1; - limited = 0; + uint8_t limited = 0; // Now limit the jerk in all axes. const float smaller_speed_factor = vmax_junction / previous_nominal_speed;