//////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// // Arc Welder: Inverse Processor (firmware simulator). // Please see the copyright notices in the function definitions // // Converts G2/G3(arc) commands back to G0/G1 commands. Intended to test firmware changes to improve arc support. // This reduces file size and the number of gcodes per second. // // Based on arc interpolation implementations from: // Marlin 1.x (see https://github.com/MarlinFirmware/Marlin/blob/1.0.x/LICENSE for the current license) // Marlin 2.x (see https://github.com/MarlinFirmware/Marlin/blob/2.0.x/LICENSE for the current license) // Prusa-Firmware (see https://github.com/prusa3d/Prusa-Firmware/blob/MK3/LICENSE for the current license) // Smoothieware (see https://github.com/Smoothieware/Smoothieware for the current license) // Repetier (see https://github.com/repetier/Repetier-Firmware for the current license) // // Built using the 'Arc Welder: Anti Stutter' library // // Copyright(C) 2021 - Brad Hochgesang //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// // This program is free software : you can redistribute it and/or modify // it under the terms of the GNU Affero General Public License as published // by the Free Software Foundation, either version 3 of the License, or // (at your option) any later version. // // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.See the // GNU Affero General Public License for more details. // // // You can contact the author at the following email address: // FormerLurker@pm.me //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// #include "marlin_1.h" #include "utilities.h" marlin_1::marlin_1(firmware_arguments args) : firmware(args) { feedrate_mm_s = 0; current_position = new float[MARLIN_XYZE]; apply_arguments(); }; marlin_1::~marlin_1() { delete current_position; } void marlin_1::apply_arguments() { static const std::vector marlin_1_firmware_version_names{ "1.1.9.1" }; set_versions(marlin_1_firmware_version_names, "1.1.9.1"); marlin_1_version_ = (marlin_1::marlin_1_firmware_versions)version_index_; std::vector used_arguments; /* Add case statement if we ever add any additional firmware versions switch (marlin_1_version_) { default:*/ plan_arc_ = &marlin_1::plan_arc_1_1_9_1; used_arguments = { FIRMWARE_ARGUMENT_MM_PER_ARC_SEGMENT, FIRMWARE_ARGUMENT_N_ARC_CORRECTION, FIRMWARE_ARGUMENT_G90_G91_INFLUENCES_EXTRUDER }; //break; //} args_.set_used_arguments(used_arguments); } firmware_arguments marlin_1::get_default_arguments_for_current_version() const { // Start off with the current args so they are set up correctly for this firmware type and version firmware_arguments default_args = args_; // firmware defaults default_args.g90_g91_influences_extruder = false; // Add the switch in here in case we want to add more versions. //switch (marlin_1_version_) //{ //default: // Active Settings default_args.mm_per_arc_segment = 1.0f; default_args.n_arc_correction = 25; //break; //} return default_args; } std::string marlin_1::interpolate_arc(firmware_position& target, double i, double j, double r, bool is_clockwise) { // Clear the current list of gcodes gcodes_.clear(); // Setup the current position current_position[X_AXIS] = static_cast(position_.x); current_position[Y_AXIS] = static_cast(position_.y); current_position[Z_AXIS] = static_cast(position_.z); current_position[E_AXIS] = static_cast(position_.e); float marlin_target[MARLIN_XYZE]; marlin_target[X_AXIS] = static_cast(target.x); marlin_target[Y_AXIS] = static_cast(target.y); marlin_target[Z_AXIS] = static_cast(target.z); marlin_target[E_AXIS] = static_cast(target.e); float marlin_offset[2]; marlin_offset[0] = static_cast(i); marlin_offset[1] = static_cast(j); // TODO: handle R form!! // Set the feedrate feedrate_mm_s = static_cast(target.f); uint8_t marlin_isclockwise = is_clockwise ? 1 : 0; (this->*plan_arc_)(marlin_target, marlin_offset, marlin_isclockwise); return gcodes_; } ///

/// This function was adapted from the 1.1.9.1 release of Marlin firmware, which can be found at the following link: /// https://github.com/MarlinFirmware/Marlin/blob/1314b31d97bba8cd74c6625c47176d4692f57790/Marlin/Marlin_main.cpp /// Copyright Notice found on that page: /// /// /// Marlin 3D Printer Firmware /// Copyright (C) 2016, 2017 MarlinFirmware [https://github.com/MarlinFirmware/Marlin] /// /// Based on Sprinter and grbl. /// Copyright (C) 2011 Camiel Gubbels / Erik van der Zalm /// /// This program is free software: you can redistribute it and/or modify /// it under the terms of the GNU General Public License as published by /// the Free Software Foundation, either version 3 of the License, or /// (at your option) any later version. /// /// This program is distributed in the hope that it will be useful, /// but WITHOUT ANY WARRANTY; without even the implied warranty of /// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the /// GNU General Public License for more details. /// /// You should have received a copy of the GNU General Public License /// along with this program. If not, see . ///

/// The target position /// The I and J offset /// Is the motion clockwise or counterclockwise void marlin_1::plan_arc_1_1_9_1(const float(&cart)[MARLIN_XYZE], // Destination position const float(&offset)[2], // Center of rotation relative to current_position const bool clockwise // Clockwise? ) { // cnc workspace planes variables -- Note: This is NOT implemented, but is added for completeness in case it is in the future. int active_extruder = 0; AxisEnum p_axis, q_axis, l_axis; p_axis = X_AXIS, q_axis = Y_AXIS, l_axis = Z_AXIS; // Radius vector from center to current location float r_P = -offset[0], r_Q = -offset[1]; const float radius = utilities::hypotf(r_P, r_Q), center_P = current_position[p_axis] - r_P, center_Q = current_position[q_axis] - r_Q, rt_X = cart[p_axis] - center_P, rt_Y = cart[q_axis] - center_Q, linear_travel = cart[l_axis] - current_position[l_axis], extruder_travel = cart[E_CART] - current_position[E_CART]; // CCW angle of rotation between position and target from the circle center. Only one atan2() trig computation required. float angular_travel = (float)utilities::atan2((double)r_P * rt_Y - (double)r_Q * rt_X, (double)r_P * rt_X + (double)r_Q * rt_Y); if (angular_travel < 0) angular_travel += utilities::radiansf(360.0f); if (clockwise) angular_travel -= utilities::radiansf(360.0f); // Make a circle if the angular rotation is 0 and the target is current position if (angular_travel == 0 && current_position[p_axis] == cart[p_axis] && current_position[q_axis] == cart[q_axis]) angular_travel = utilities::radiansf(360.0f); const float flat_mm = radius * angular_travel, mm_of_travel = linear_travel ? utilities::hypotf(flat_mm, linear_travel) : utilities::absf(flat_mm); if (mm_of_travel < 0.001f) return; uint16_t segments = (uint16_t)utilities::floorf(mm_of_travel / (float)(args_.mm_per_arc_segment)); NOLESS(segments, 1); /** * Vector rotation by transformation matrix: r is the original vector, r_T is the rotated vector, * and phi is the angle of rotation. Based on the solution approach by Jens Geisler. * r_T = [cos(phi) -sin(phi); * sin(phi) cos(phi)] * r ; * * For arc generation, the center of the circle is the axis of rotation and the radius vector is * defined from the circle center to the initial position. Each line segment is formed by successive * vector rotations. This requires only two cos() and sin() computations to form the rotation * matrix for the duration of the entire arc. Error may accumulate from numerical round-off, since * all double numbers are single precision on the Arduino. (True double precision will not have * round off issues for CNC applications.) Single precision error can accumulate to be greater than * tool precision in some cases. Therefore, arc path correction is implemented. * * Small angle approximation may be used to reduce computation overhead further. This approximation * holds for everything, but very small circles and large MM_PER_ARC_SEGMENT values. In other words, * theta_per_segment would need to be greater than 0.1 rad and N_ARC_CORRECTION would need to be large * to cause an appreciable drift error. N_ARC_CORRECTION~=25 is more than small enough to correct for * numerical drift error. N_ARC_CORRECTION may be on the order a hundred(s) before error becomes an * issue for CNC machines with the single precision Arduino calculations. * * This approximation also allows plan_arc to immediately insert a line segment into the planner * without the initial overhead of computing cos() or sin(). By the time the arc needs to be applied * a correction, the planner should have caught up to the lag caused by the initial plan_arc overhead. * This is important when there are successive arc motions. */ // Vector rotation matrix values float raw[MARLIN_XYZE]; const float theta_per_segment = angular_travel / segments, linear_per_segment = linear_travel / segments, extruder_per_segment = extruder_travel / segments, sin_T = theta_per_segment, cos_T = 1 - 0.5f * utilities::sqf(theta_per_segment); // Small angle approximation // Initialize the linear axis raw[l_axis] = current_position[l_axis]; // Initialize the extruder axis raw[E_CART] = current_position[E_CART]; const float fr_mm_s = MMS_SCALED(feedrate_mm_s); int8_t arc_recalc_count = 0; if (args_.n_arc_correction > 1) { arc_recalc_count = args_.n_arc_correction; } for (uint16_t i = 1; i < segments; i++) // Iterate (segments-1) times { if (args_.n_arc_correction > 1 && --arc_recalc_count) { // Apply vector rotation matrix to previous r_P / 1 const float r_new_Y = r_P * sin_T + r_Q * cos_T; r_P = r_P * cos_T - r_Q * sin_T; r_Q = r_new_Y; } else { if (args_.n_arc_correction > 1) { arc_recalc_count = args_.n_arc_correction; } // Arc correction to radius vector. Computed only every N_ARC_CORRECTION increments. // Compute exact location by applying transformation matrix from initial radius vector(=-offset). // To reduce stuttering, the sin and cos could be computed at different times. // For now, compute both at the same time. const float cos_Ti = (float)utilities::cos(i * (double)theta_per_segment), sin_Ti = (float)utilities::sin(i * (double)theta_per_segment); r_P = -offset[0] * cos_Ti + offset[1] * sin_Ti; r_Q = -offset[0] * sin_Ti - offset[1] * cos_Ti; } // Update raw location raw[p_axis] = center_P + r_P; raw[q_axis] = center_Q + r_Q; raw[l_axis] += linear_per_segment; raw[E_CART] += extruder_per_segment; clamp_to_software_endstops(raw); if (!buffer_line_kinematic(raw, feedrate_mm_s, active_extruder)) break; } buffer_line_kinematic(cart, feedrate_mm_s, active_extruder); COPY(current_position, cart); } void marlin_1::NOLESS(uint16_t &x, uint16_t y) { if (x < y) x = y; } float marlin_1::MMS_SCALED(float x) { // No scaling return x; } void marlin_1::COPY(float target[MARLIN_XYZE], const float(&source)[MARLIN_XYZE]) { // This is a slow copy, but speed isn't much of an issue here. for (int i = 0; i < MARLIN_XYZE; i++) { target[i] = source[i]; } } void marlin_1::clamp_to_software_endstops(const float(&raw)[MARLIN_XYZE]) { // Do nothing, just added to keep mc_arc identical to the firmware version return; } //void marlin::buffer_line_kinematic(float x, float y, float z, const float& e, float feed_rate, uint8_t extruder, const float* gcode_target) bool marlin_1::buffer_line_kinematic(const float(&cart)[MARLIN_XYZE], double fr_mm_s, int active_extruder) { // create the target position firmware_position target; target.x = cart[AxisEnum::X_AXIS]; target.y = cart[AxisEnum::Y_AXIS]; target.z = cart[AxisEnum::Z_AXIS]; target.e = cart[AxisEnum::E_AXIS]; target.f = fr_mm_s; if (gcodes_.size() > 0) { gcodes_ += "\n"; } // Generate the gcode gcodes_ += g1_command(target); // update the current position set_current_position(target); return true; }