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--- et:projects:3pi:solutions [2015/11/05 12:05] – kaupo.raid
+++ et:projects:3pi:solutions [2020/07/20 09:00] (current) – external edit 127.0.0.1
@@ Line 144: / Line 144: @@
 </code>
+==3Pi PID regulaatoriga joonejärgimine==
+<code c>
+/*
+ * 3pi-linefollower-pid - demo code for the Pololu 3pi Robot
+ *
+ * This code will follow a black line on a white background, using a
+ * PID-based algorithm.
+ *
+ * http://www.pololu.com/docs/0J21
+ * http://www.pololu.com
+ * http://forum.pololu.com
+ *
+ */
+// The 3pi include file must be at the beginning of any program that
+// uses the Pololu AVR library and 3pi.
+#include <pololu/3pi.h>
+// This include file allows data to be stored in program space.  The
+// ATmega168 has 16k of program space compared to 1k of RAM, so large
+// pieces of static data should be stored in program space.
+#include <avr/pgmspace.h>
+// Introductory messages.  The "PROGMEM" identifier causes the data to
+// go into program space.
+const char welcome_line1[] PROGMEM = " Pololu";
+const char welcome_line2[] PROGMEM = "3\xf7 Robot";
+const char demo_name_line1[] PROGMEM = "PID Line";
+const char demo_name_line2[] PROGMEM = "follower";
+// A couple of simple tunes, stored in program space.
+const char welcome[] PROGMEM = ">g32>>c32";
+const char go[] PROGMEM = "L16 cdegreg4";
+// Data for generating the characters used in load_custom_characters
+// and display_readings.  By reading levels[] starting at various
+// offsets, we can generate all of the 7 extra characters needed for a
+// bargraph.  This is also stored in program space.
+const char levels[] PROGMEM = {
+b00000,
+b00000,
+b00000,
+b00000,
+b00000,
+b00000,
+b00000,
+b11111,
+b11111,
+b11111,
+b11111,
+b11111,
+b11111,
+b11111
+};
+// This function loads custom characters into the LCD.  Up to 8
+// characters can be loaded; we use them for 7 levels of a bar graph.
+void load_custom_characters()
+{
+	lcd_load_custom_character(levels+0,0); // no offset, e.g. one bar
+	lcd_load_custom_character(levels+1,1); // two bars
+	lcd_load_custom_character(levels+2,2); // etc...
+	lcd_load_custom_character(levels+3,3);
+	lcd_load_custom_character(levels+4,4);
+	lcd_load_custom_character(levels+5,5);
+	lcd_load_custom_character(levels+6,6);
+	clear(); // the LCD must be cleared for the characters to take effect
+}
+// This function displays the sensor readings using a bar graph.
+void display_readings(const unsigned int *calibrated_values)
+{
+	unsigned char i;
+	for(i=0;i<5;i++) {
+		// Initialize the array of characters that we will use for the
+		// graph.  Using the space, an extra copy of the one-bar
+		// character, and character 255 (a full black box), we get 10
+		// characters in the array.
+		const char display_characters[10] = {' ',0,0,1,2,3,4,5,6,255};
+		// The variable c will have values from 0 to 9, since
+		// calibrated values are in the range of 0 to 1000, and
+		// 1000/101 is 9 with integer math.
+		char c = display_characters[calibrated_values[i]/101];
+		// Display the bar graph character.
+		print_character(c);
+	}
+}
+// Initializes the 3pi, displays a welcome message, calibrates, and
+// plays the initial music.
+void initialize()
+{
+	unsigned int counter; // used as a simple timer
+	unsigned int sensors[5]; // an array to hold sensor values
+	// This must be called at the beginning of 3pi code, to set up the
+	// sensors.  We use a value of 2000 for the timeout, which
+	// corresponds to 2000*0.4 us = 0.8 ms on our 20 MHz processor.
+	pololu_3pi_init(2000);
+	load_custom_characters(); // load the custom characters
+	// Play welcome music and display a message
+	print_from_program_space(welcome_line1);
+	lcd_goto_xy(0,1);
+	print_from_program_space(welcome_line2);
+	play_from_program_space(welcome);
+	delay_ms(1000);
+	clear();
+	print_from_program_space(demo_name_line1);
+	lcd_goto_xy(0,1);
+	print_from_program_space(demo_name_line2);
+	delay_ms(1000);
+	// Display battery voltage and wait for button press
+	while(!button_is_pressed(BUTTON_B))
+	{
+		int bat = read_battery_millivolts();
+		clear();
+		print_long(bat);
+		print("mV");
+		lcd_goto_xy(0,1);
+		print("Press B");
+		delay_ms(100);
+	}
+	// Always wait for the button to be released so that 3pi doesn't
+	// start moving until your hand is away from it.
+	wait_for_button_release(BUTTON_B);
+	delay_ms(1000);
+	// Auto-calibration: turn right and left while calibrating the
+	// sensors.
+	for(counter=0;counter<80;counter++)
+	{
+		if(counter < 20 || counter >= 60)
+			set_motors(40,-40);
+		else
+			set_motors(-40,40);
+		// This function records a set of sensor readings and keeps
+		// track of the minimum and maximum values encountered.  The
+		// IR_EMITTERS_ON argument means that the IR LEDs will be
+		// turned on during the reading, which is usually what you
+		// want.
+		calibrate_line_sensors(IR_EMITTERS_ON);
+		// Since our counter runs to 80, the total delay will be
+		// 80*20 = 1600 ms.
+		delay_ms(20);
+	}
+	set_motors(0,0);
+	// Display calibrated values as a bar graph.
+	while(!button_is_pressed(BUTTON_B))
+	{
+		// Read the sensor values and get the position measurement.
+		unsigned int position = read_line(sensors,IR_EMITTERS_ON);
+		// Display the position measurement, which will go from 0
+		// (when the leftmost sensor is over the line) to 4000 (when
+		// the rightmost sensor is over the line) on the 3pi, along
+		// with a bar graph of the sensor readings.  This allows you
+		// to make sure the robot is ready to go.
+		clear();
+		print_long(position);
+		lcd_goto_xy(0,1);
+		display_readings(sensors);
+		delay_ms(100);
+	}
+	wait_for_button_release(BUTTON_B);
+	clear();
+	print("Go!");
+	// Play music and wait for it to finish before we start driving.
+	play_from_program_space(go);
+	while(is_playing());
+}
+// This is the main function, where the code starts.  All C programs
+// must have a main() function defined somewhere.
+int main()
+{
+	unsigned int sensors[5]; // an array to hold sensor values
+	unsigned int last_proportional=0;
+	long integral=0;
+	// set up the 3pi
+	initialize();
+	// This is the "main loop" - it will run forever.
+	while(1)
+	{
+		// Get the position of the line.  Note that we *must* provide
+		// the "sensors" argument to read_line() here, even though we
+		// are not interested in the individual sensor readings.
+		unsigned int position = read_line(sensors,IR_EMITTERS_ON);
+		// The "proportional" term should be 0 when we are on the line.
+		int proportional = ((int)position) - 2000;
+		// Compute the derivative (change) and integral (sum) of the
+		// position.
+		int derivative = proportional - last_proportional;
+		integral += proportional;
+		// Remember the last position.
+		last_proportional = proportional;
+		// Compute the difference between the two motor power settings,
+		// m1 - m2.  If this is a positive number the robot will turn
+		// to the right.  If it is a negative number, the robot will
+		// turn to the left, and the magnitude of the number determines
+		// the sharpness of the turn.
+		int power_difference = proportional/20 + integral/10000 + derivative*3/2;
+		// Compute the actual motor settings.  We never set either motor
+		// to a negative value.
+		const int max = 60;
+		if(power_difference > max)
+			power_difference = max;
+		if(power_difference < -max)
+			power_difference = -max;
+		if(power_difference < 0)
+			set_motors(max+power_difference, max);
+		else
+			set_motors(max, max-power_difference);
+	}
+	// This part of the code is never reached.  A robot should
+	// never reach the end of its program, or unpredictable behavior
+	// will result as random code starts getting executed.  If you
+	// really want to stop all actions at some point, set your motors
+	// to 0,0 and run the following command to loop forever:
+	//
+	// while(1);
+}
+// Local Variables: **
+// mode: C **
+// c-basic-offset: 4 **
+// tab-width: 4 **
+// indent-tabs-mode: t **
+// end: **
+</code>

et/projects/3pi/solutions.1446725131.txt.gz · Last modified: 2020/07/20 09:00 (external edit)