root / trunk / code / projects / libdragonfly / move.c @ 1461
History | View | Annotate | Download (5.29 KB)
1 |
/**
|
---|---|
2 |
* Copyright (c) 2007 Colony Project
|
3 |
*
|
4 |
* Permission is hereby granted, free of charge, to any person
|
5 |
* obtaining a copy of this software and associated documentation
|
6 |
* files (the "Software"), to deal in the Software without
|
7 |
* restriction, including without limitation the rights to use,
|
8 |
* copy, modify, merge, publish, distribute, sublicense, and/or sell
|
9 |
* copies of the Software, and to permit persons to whom the
|
10 |
* Software is furnished to do so, subject to the following
|
11 |
* conditions:
|
12 |
*
|
13 |
* The above copyright notice and this permission notice shall be
|
14 |
* included in all copies or substantial portions of the Software.
|
15 |
*
|
16 |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
|
17 |
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
|
18 |
* OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
19 |
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
|
20 |
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
|
21 |
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
22 |
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
|
23 |
* OTHER DEALINGS IN THE SOFTWARE.
|
24 |
**/
|
25 |
|
26 |
|
27 |
/**
|
28 |
* @file move.c
|
29 |
* @brief Functions for moving
|
30 |
*
|
31 |
* Implementation of functions for moving the robot.
|
32 |
*
|
33 |
* @author Colony Project, CMU Robotics Club
|
34 |
**/
|
35 |
|
36 |
#include "move.h" |
37 |
#include "motor.h" |
38 |
#include "rangefinder.h" |
39 |
|
40 |
|
41 |
// Internal prototypes
|
42 |
void translateAngulartoLinear (int velocity, int omega, int* vl, int* vr); |
43 |
|
44 |
// global varaibles for move_avoid
|
45 |
int d1, d2, d3, d4, d5;
|
46 |
/**
|
47 |
* @defgroup move Movement
|
48 |
* @brief Functions fo controlling robot motion
|
49 |
* Higher level functions to control the movement of robots.
|
50 |
*
|
51 |
* @{
|
52 |
**/
|
53 |
|
54 |
|
55 |
/**
|
56 |
* Causes the robot to move with the given translation and rotational velocities.
|
57 |
* motors_init must be called before this function can be used.
|
58 |
*
|
59 |
* @param velocity the translational velocity of the robot, in the range -255 to 255.
|
60 |
* A positive value indicates forward motion, while a negative value indicates
|
61 |
* backwards motion.
|
62 |
*
|
63 |
* @param omega the rotational velocity of the robot, in the range -255 to 255.
|
64 |
* A positive value indicates a counterclockwise velocity, while a negative
|
65 |
* value indicates a clockwise velocity.
|
66 |
*
|
67 |
* @see motors_init, motor1_set, motor2_set
|
68 |
**/
|
69 |
void move (int velocity, int omega) { |
70 |
int vl = 0; |
71 |
int vr = 0; |
72 |
translateAngulartoLinear(velocity, omega, &vl , &vr ); |
73 |
//
|
74 |
|
75 |
if (vl < 0) { |
76 |
motor1_set(BACKWARD, -vl); |
77 |
} else {
|
78 |
motor1_set(FORWARD, vl); |
79 |
} |
80 |
if (vr < 0) { |
81 |
motor2_set(BACKWARD, -vr); |
82 |
} else {
|
83 |
motor2_set(FORWARD, vr); |
84 |
} |
85 |
} |
86 |
|
87 |
|
88 |
/**
|
89 |
* Moves the robot with the given translational and angular velocities
|
90 |
* while avoiding obstacles. To be effective, this function must be
|
91 |
* called repeatedly throughout the motion. It relies on the IR
|
92 |
* rangefinders to detect obstacles. Before calling this function,
|
93 |
* motors_init and range_init must be called.
|
94 |
*
|
95 |
* @param velocity the translational velocity of the robot, in the
|
96 |
* range -255 to 255. A positive value indicates forward motion.
|
97 |
*
|
98 |
* @param omega the rotational velocity of the robot, in the range
|
99 |
* -255 to 255. A positive value indicates a counterclockwise velocity.
|
100 |
*
|
101 |
* @param strength the strength of the avoid behavior, in the range
|
102 |
* 0 to 100.
|
103 |
*
|
104 |
* @see motors_init, range_init, move
|
105 |
**/
|
106 |
void move_avoid(int velocity, int omega, int strength) { |
107 |
int pControl;
|
108 |
int vl = 0; |
109 |
int vr = 0; |
110 |
int temp;
|
111 |
|
112 |
temp=range_read_distance(IR1); |
113 |
d1 = (temp == -1) ? d1 : temp;
|
114 |
|
115 |
temp=range_read_distance(IR2); |
116 |
d2=(temp == -1) ? d2 : temp;
|
117 |
|
118 |
temp=range_read_distance(IR3); |
119 |
d3=(temp == -1) ? d3 : temp;
|
120 |
|
121 |
temp=range_read_distance(IR4); |
122 |
d4=(temp == -1) ? d4 : temp;
|
123 |
|
124 |
temp=range_read_distance(IR5); |
125 |
d5=(temp == -1) ? d5 : temp;
|
126 |
|
127 |
/* Avoid obstacles ahead
|
128 |
if(d2>170)
|
129 |
v*=-1;
|
130 |
|
131 |
Naturally slow down if there is something in the way.
|
132 |
if(d2>150 || d1>180 || d3>180){
|
133 |
v>>=1;
|
134 |
*/
|
135 |
|
136 |
//pControl= (((d3-d1) + (d4-d5))*strength)/100;
|
137 |
pControl= (((d5-d4))*strength)/100;
|
138 |
omega = (omega*(100-strength))/100 + pControl; |
139 |
translateAngulartoLinear(velocity, omega, &vl , &vr ); |
140 |
|
141 |
if (vl < 0) { |
142 |
motor1_set(BACKWARD, -vl); |
143 |
} else {
|
144 |
motor1_set(FORWARD, vl); |
145 |
} |
146 |
if (vr < 0) { |
147 |
motor2_set(BACKWARD, -vr); |
148 |
} else {
|
149 |
motor2_set(FORWARD, vr); |
150 |
} |
151 |
} |
152 |
|
153 |
/**@}**///end the motion group |
154 |
|
155 |
void translateAngulartoLinear (int velocity, int omega, int* vl, int* vr) { |
156 |
//omega: angle measure, positive couter-clockwise from front.
|
157 |
// -180 <= omega <= 180
|
158 |
//velocity: -255 <= velocity <= 255
|
159 |
|
160 |
long int vltemp, vrtemp; |
161 |
|
162 |
//make sure values are in bounds
|
163 |
if (velocity < -255 || velocity >255 || omega < -255 || omega > 255) return; |
164 |
|
165 |
//compute
|
166 |
vrtemp = velocity + omega * 3;
|
167 |
vltemp = velocity - omega * 3;
|
168 |
|
169 |
//check to see if max linear velocities have been exceeded.
|
170 |
if (vrtemp > 255) { |
171 |
vltemp = 255 * vltemp / vrtemp;
|
172 |
vrtemp = 255;
|
173 |
} |
174 |
if (vltemp > 255) { |
175 |
vrtemp = 255 * vrtemp / vltemp;
|
176 |
vltemp = 255;
|
177 |
} |
178 |
if (vrtemp < -255) { |
179 |
vltemp = -255 * vltemp / vrtemp;
|
180 |
vrtemp = -255;
|
181 |
} |
182 |
if (vltemp < -255) { |
183 |
vrtemp = -255 * vrtemp / vltemp;
|
184 |
vltemp = -255;
|
185 |
} |
186 |
|
187 |
*vr = (int)vrtemp;
|
188 |
*vl = (int)vltemp;
|
189 |
} |