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authorNicolas Schodet2008-01-28 21:12:12 +0100
committerNicolas Schodet2008-01-28 21:12:12 +0100
commitbc38b408c53281ee985f6f9d67accc5733d99e37 (patch)
treeeb4626232c03e3c25f5b508e3b8f57a539971fb4 /digital/asserv/src/asserv/speed.c
parent837b9fe53240e8cbbd76bd9ba9b6a9a3cd9bc891 (diff)
* digital/asserv/src/asserv:
- imported old sources. - removed holes support (rule 2006).
Diffstat (limited to 'digital/asserv/src/asserv/speed.c')
-rw-r--r--digital/asserv/src/asserv/speed.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/digital/asserv/src/asserv/speed.c b/digital/asserv/src/asserv/speed.c
new file mode 100644
index 00000000..7e8ed558
--- /dev/null
+++ b/digital/asserv/src/asserv/speed.c
@@ -0,0 +1,123 @@
+/* speed.c - Speed control. */
+/* asserv - Position & speed motor control on AVR. {{{
+ *
+ * Copyright (C) 2005 Nicolas Schodet
+ *
+ * Robot APB Team/Efrei 2006.
+ * Web: http://assos.efrei.fr/robot/
+ * Email: robot AT efrei DOT fr
+ *
+ * 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 2 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * }}} */
+
+/**
+ * This file is responsible for speed control. It changes the current shafts
+ * positions using ramps. It can be controlled by a wanted speed or wanted
+ * shaft position.
+ */
+
+/** Current speed, f8.8. */
+int16_t speed_theta_cur, speed_alpha_cur;
+/** Consign speed, f8.8. */
+int16_t speed_theta_cons, speed_alpha_cons;
+/** Maximum speed for position consign, u8. */
+int8_t speed_theta_max, speed_alpha_max;
+/** Slow speed for position consign, u8. */
+int8_t speed_theta_slow, speed_alpha_slow;
+/** Consign position. */
+uint32_t speed_theta_pos_cons, speed_alpha_pos_cons;
+/** Weither to use the consign position (1) or not (0). */
+uint8_t speed_pos;
+
+/** Acceleration, uf8.8. */
+int16_t speed_theta_acc, speed_alpha_acc;
+
+/* +AutoDec */
+/* -AutoDec */
+
+/** Update shaft position consign according to a speed consign. */
+static void
+speed_update_by_speed (void)
+{
+ /* Update current speed. */
+ if (UTILS_ABS (speed_theta_cons - speed_theta_cur) < speed_theta_acc)
+ speed_theta_cur = speed_theta_cons;
+ else if (speed_theta_cons > speed_theta_cur)
+ speed_theta_cur += speed_theta_acc;
+ else
+ speed_theta_cur -= speed_theta_acc;
+ if (UTILS_ABS (speed_alpha_cons - speed_alpha_cur) < speed_alpha_acc)
+ speed_alpha_cur = speed_alpha_cons;
+ else if (speed_alpha_cons > speed_alpha_cur)
+ speed_alpha_cur += speed_alpha_acc;
+ else
+ speed_alpha_cur -= speed_alpha_acc;
+}
+
+/** Compute maximum allowed speed according to: distance left, maximum speed,
+ * current speed and acceleration. */
+static int16_t
+speed_compute_max_speed (int32_t d, int16_t cur, int16_t acc, int8_t max)
+{
+ int16_t s;
+ /* Compute maximum speed in order to be able to brake in time.
+ * s = sqrt (2 * a * d) */
+ s = fixed_sqrt_ui32 (2 * (acc >> 8) * UTILS_ABS (d));
+ /* Apply consign. */
+ s = UTILS_MIN (max, s);
+ /* Apply sign. */
+ if (d < 0)
+ s = -s;
+ /* Convert to f8.8 and check acceleration. */
+ s = s << 8;
+ UTILS_BOUND (s, cur - acc, cur + acc);
+ return s;
+}
+
+/** Update shaft position consign according to a position consign. */
+static void
+speed_update_by_position (void)
+{
+ int32_t theta_d = speed_theta_pos_cons - pos_theta_cons;
+ int32_t alpha_d = speed_alpha_pos_cons - pos_alpha_cons;
+ if (theta_d >= -speed_theta_max && theta_d <= speed_theta_max)
+ speed_theta_cur = theta_d << 8;
+ else
+ speed_theta_cur = speed_compute_max_speed (theta_d, speed_theta_cur,
+ speed_theta_acc, speed_theta_max);
+ if (alpha_d >= -speed_alpha_max && alpha_d <= speed_alpha_max)
+ speed_alpha_cur = alpha_d << 8;
+ else
+ speed_alpha_cur = speed_compute_max_speed (alpha_d, speed_alpha_cur,
+ speed_alpha_acc, speed_alpha_max);
+ if (speed_theta_cur == 0 && speed_alpha_cur == 0)
+ main_sequence_finish = main_sequence;
+}
+
+/** Update shaft position consign according to consign. */
+static void
+speed_update (void)
+{
+ /* Update speed. */
+ if (speed_pos)
+ speed_update_by_position ();
+ else
+ speed_update_by_speed ();
+ /* Update shaft position. */
+ pos_theta_cons += speed_theta_cur >> 8;
+ pos_alpha_cons += speed_alpha_cur >> 8;
+}
+