63 lines
2.8 KiB
C
63 lines
2.8 KiB
C
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/*
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acceleration.c - support methods for acceleration-related calcul
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Part of Grbl
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Copyright (c) 2009 Simen Svale Skogsrud
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Grbl is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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Grbl is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with Grbl. If not, see <http://www.gnu.org/licenses/>.
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*/
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// Estimate the maximum speed at a given distance when you need to reach the given
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// target_velocity with max_accelleration.
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double estimate_max_speed(double max_accelleration, double target_velocity, double distance) {
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return(sqrt(-2*max_accelleration*distance+target_velocity*target_velocity))
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}
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// At what distance must we start accellerating/braking to reach target_speed from current_speed given the
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// specified constant accelleration.
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double estimate_brake_distance(double current_speed, double target_speed, double acceleration) {
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return((target_speed*target_speed-current_speed*current_speed)/(2*acceleration));
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}
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// Calculate feed rate in length-units/second for a single axis
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double axis_feed_rate(double steps_per_stepping, uint32_t stepping_rate, double steps_per_unit) {
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if (stepping_rate == 0) { return(0.0); }
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return((TICKS_PER_MICROSECOND*1000000)*steps_per_stepping/(stepping_rate*steps_per_unit));
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}
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// The 'swerve' of a joint is equal to the maximum accelleration of any single
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// single axis in the corner between the outgoing and the incoming line. Accelleration control
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// will regulate speed to avoid excessive swerve.
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double calculate_swerve(struct Line* outgoing, struct Line* incoming) {
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double x_swerve = abs(
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axis_feed_rate(
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((double)incoming->steps_x)/incoming->maximum_steps, incoming->rate, settings.steps_per_mm[X_AXIS])
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- axis_feed_rate(
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((double)incoming->steps_x)/incoming->maximum_steps, outgoing-> rate, settings.steps_per_mm[X_AXIS]));
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double y_swerve = abs(
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axis_feed_rate(
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((double)incoming->steps_y)/incoming->maximum_steps, incoming->rate, settings.steps_per_mm[Y_AXIS])
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- axis_feed_rate(
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((double)incoming->steps_y)/incoming->maximum_steps, outgoing-> rate, settings.steps_per_mm[Y_AXIS]));
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double z_swerve = abs(
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axis_feed_rate(
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((double)incoming->steps_z)/incoming->maximum_steps, incoming->rate, settings.steps_per_mm[Z_AXIS])
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- axis_feed_rate(
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((double)incoming->steps_z)/incoming->maximum_steps, outgoing-> rate, settings.steps_per_mm[Z_AXIS]));
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return max(x_swerve, max(y_swerve, z_swerve));
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}
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