To use freeIMU processing visualization tool, I have implemented float number transmission over uart (default /dev/ttyS2, 115200)

But this not tested yet. I should.
This commit is contained in:
Hyon Lim (Retina)
2013-05-22 13:03:14 +10:00
parent f547044203
commit 364d1a06e3
@@ -47,6 +47,10 @@ static int attitude_estimator_so3_comp_task; /**< Handle of deamon task / thr
static float q0 = 1.0f, q1 = 0.0f, q2 = 0.0f, q3 = 0.0f; // quaternion of sensor frame relative to auxiliary frame
static float integralFBx = 0.0f, integralFBy = 0.0f, integralFBz = 0.0f; // integral error terms scaled by Ki
//! Serial packet related
static int uart;
static int baudrate;
/**
* Mainloop of attitude_estimator_so3_comp.
*/
@@ -63,7 +67,9 @@ usage(const char *reason)
if (reason)
fprintf(stderr, "%s\n", reason);
fprintf(stderr, "usage: attitude_estimator_so3_comp {start|stop|status} [-p <additional params>]\n\n");
fprintf(stderr, "usage: attitude_estimator_so3_comp {start|stop|status} [-d <devicename>] [-b <baud rate>]\n"
"-d and -b options are for separate visualization with raw data (quaternion packet) transfer\n"
"ex) attitude_estimator_so3_comp start -d /dev/ttyS1 -b 115200\n");
exit(1);
}
@@ -80,6 +86,8 @@ int attitude_estimator_so3_comp_main(int argc, char *argv[])
if (argc < 1)
usage("missing command");
if (!strcmp(argv[1], "start")) {
if (thread_running) {
@@ -94,12 +102,18 @@ int attitude_estimator_so3_comp_main(int argc, char *argv[])
SCHED_PRIORITY_MAX - 5,
12400,
attitude_estimator_so3_comp_thread_main,
(argv) ? (const char **)&argv[2] : (const char **)NULL);
(const char **)argv);
exit(0);
}
if (!strcmp(argv[1], "stop")) {
thread_should_exit = true;
while(thread_running){
usleep(200000);
printf(".");
}
printf("terminated.");
exit(0);
}
@@ -121,76 +135,18 @@ int attitude_estimator_so3_comp_main(int argc, char *argv[])
//---------------------------------------------------------------------------------------------------
// Fast inverse square-root
// See: http://en.wikipedia.org/wiki/Fast_inverse_square_root
float invSqrt(float x) {
float halfx = 0.5f * x;
float y = x;
long i = *(long*)&y;
i = 0x5f3759df - (i>>1);
y = *(float*)&i;
y = y * (1.5f - (halfx * y * y));
return y;
}
float invSqrt(float number) {
volatile long i;
volatile float x, y;
volatile const float f = 1.5F;
void MahonyAHRSupdateIMU(float gx, float gy, float gz, float ax, float ay, float az, float twoKp, float twoKi, float dt) {
float recipNorm;
float halfvx, halfvy, halfvz;
float halfex, halfey, halfez;
// Compute feedback only if accelerometer measurement valid (avoids NaN in accelerometer normalisation)
if(!((ax == 0.0f) && (ay == 0.0f) && (az == 0.0f))) {
// Normalise accelerometer measurement
recipNorm = invSqrt(ax * ax + ay * ay + az * az);
ax *= recipNorm;
ay *= recipNorm;
az *= recipNorm;
// Estimated direction of gravity and vector perpendicular to magnetic flux
halfvx = q1 * q3 - q0 * q2;
halfvy = q0 * q1 + q2 * q3;
halfvz = q0 * q0 - 0.5f + q3 * q3;
// Error is sum of cross product between estimated and measured direction of gravity
halfex = (ay * halfvz - az * halfvy);
halfey = (az * halfvx - ax * halfvz);
halfez = (ax * halfvy - ay * halfvx);
// Compute and apply integral feedback if enabled
if(twoKi > 0.0f) {
integralFBx += twoKi * halfex * dt; // integral error scaled by Ki
integralFBy += twoKi * halfey * dt;
integralFBz += twoKi * halfez * dt;
gx += integralFBx; // apply integral feedback
gy += integralFBy;
gz += integralFBz;
}
else {
integralFBx = 0.0f; // prevent integral windup
integralFBy = 0.0f;
integralFBz = 0.0f;
}
// Apply proportional feedback
gx += twoKp * halfex;
gy += twoKp * halfey;
gz += twoKp * halfez;
}
// Integrate rate of change of quaternion
gx *= (0.5f * dt); // pre-multiply common factors
gy *= (0.5f * dt);
gz *= (0.5f * dt);
q0 +=(-q1 * gx - q2 * gy - q3 * gz);
q1 += (q0 * gx + q2 * gz - q3 * gy);
q2 += (q0 * gy - q1 * gz + q3 * gx);
q3 += (q0 * gz + q1 * gy - q2 * gx);
// Normalise quaternion
recipNorm = invSqrt(q0 * q0 + q1 * q1 + q2 * q2 + q3 * q3);
q0 *= recipNorm;
q1 *= recipNorm;
q2 *= recipNorm;
q3 *= recipNorm;
x = number * 0.5F;
y = number;
i = * (( long * ) &y);
i = 0x5f375a86 - ( i >> 1 );
y = * (( float * ) &i);
y = y * ( f - ( x * y * y ) );
return y;
}
void MahonyAHRSupdate(float gx, float gy, float gz, float ax, float ay, float az, float mx, float my, float mz, float twoKp, float twoKi, float dt) {
@@ -202,7 +158,7 @@ void MahonyAHRSupdate(float gx, float gy, float gz, float ax, float ay, float az
// Use IMU algorithm if magnetometer measurement invalid (avoids NaN in magnetometer normalisation)
if((mx == 0.0f) && (my == 0.0f) && (mz == 0.0f)) {
MahonyAHRSupdateIMU(gx, gy, gz, ax, ay, az, twoKp, twoKi, dt);
//MahonyAHRSupdateIMU(gx, gy, gz, ax, ay, az, twoKp, twoKi, dt);
return;
}
@@ -290,6 +246,117 @@ void MahonyAHRSupdate(float gx, float gy, float gz, float ax, float ay, float az
q3 *= recipNorm;
}
void send_uart_byte(char c)
{
write(uart,&c,1);
}
void send_uart_bytes(uint8_t *data, int length)
{
write(uart,data,(size_t)(sizeof(uint8_t)*length));
}
void send_uart_float(float f) {
uint8_t * b = (uint8_t *) &f;
//! Assume float is 4-bytes
for(int i=0; i<4; i++) {
uint8_t b1 = (b[i] >> 4) & 0x0f;
uint8_t b2 = (b[i] & 0x0f);
uint8_t c1 = (b1 < 10) ? ('0' + b1) : 'A' + b1 - 10;
uint8_t c2 = (b2 < 10) ? ('0' + b2) : 'A' + b2 - 10;
send_uart_bytes(&c1,1);
send_uart_bytes(&c2,1);
}
}
void send_uart_float_arr(float *arr, int length)
{
for(int i=0;i<length;++i)
{
send_uart_float(arr[i]);
send_uart_byte(',');
}
}
int open_uart(int baud, const char *uart_name, struct termios *uart_config_original, bool *is_usb)
{
int speed;
switch (baud) {
case 0: speed = B0; break;
case 50: speed = B50; break;
case 75: speed = B75; break;
case 110: speed = B110; break;
case 134: speed = B134; break;
case 150: speed = B150; break;
case 200: speed = B200; break;
case 300: speed = B300; break;
case 600: speed = B600; break;
case 1200: speed = B1200; break;
case 1800: speed = B1800; break;
case 2400: speed = B2400; break;
case 4800: speed = B4800; break;
case 9600: speed = B9600; break;
case 19200: speed = B19200; break;
case 38400: speed = B38400; break;
case 57600: speed = B57600; break;
case 115200: speed = B115200; break;
case 230400: speed = B230400; break;
case 460800: speed = B460800; break;
case 921600: speed = B921600; break;
default:
fprintf(stderr, "ERROR: Unsupported baudrate: %d\n\tsupported examples:\n\n\t9600\n19200\n38400\n57600\n115200\n230400\n460800\n921600\n\n", baud);
return -EINVAL;
}
printf("[mavlink] UART is %s, baudrate is %d\n", uart_name, baud);
uart = open(uart_name, O_RDWR | O_NOCTTY);
/* Try to set baud rate */
struct termios uart_config;
int termios_state;
*is_usb = false;
/* make some wild guesses including that USB serial is indicated by either /dev/ttyACM0 or /dev/console */
if (strcmp(uart_name, "/dev/ttyACM0") != OK && strcmp(uart_name, "/dev/console") != OK) {
/* Back up the original uart configuration to restore it after exit */
if ((termios_state = tcgetattr(uart, uart_config_original)) < 0) {
fprintf(stderr, "ERROR getting baudrate / termios config for %s: %d\n", uart_name, termios_state);
close(uart);
return -1;
}
/* Fill the struct for the new configuration */
tcgetattr(uart, &uart_config);
/* Clear ONLCR flag (which appends a CR for every LF) */
uart_config.c_oflag &= ~ONLCR;
/* Set baud rate */
if (cfsetispeed(&uart_config, speed) < 0 || cfsetospeed(&uart_config, speed) < 0) {
fprintf(stderr, "ERROR setting baudrate / termios config for %s: %d (cfsetispeed, cfsetospeed)\n", uart_name, termios_state);
close(uart);
return -1;
}
if ((termios_state = tcsetattr(uart, TCSANOW, &uart_config)) < 0) {
fprintf(stderr, "ERROR setting baudrate / termios config for %s (tcsetattr)\n", uart_name);
close(uart);
return -1;
}
} else {
*is_usb = true;
}
return uart;
}
/*
* [Rot_matrix,x_aposteriori,P_aposteriori] = attitudeKalmanfilter(dt,z_k,x_aposteriori_k,P_aposteriori_k,knownConst)
*/
@@ -307,6 +374,15 @@ int attitude_estimator_so3_comp_thread_main(int argc, char *argv[])
const unsigned int loop_interval_alarm = 6500; // loop interval in microseconds
//! Serial debug related
int ch;
struct termios uart_config_original;
bool usb_uart;
bool debug_mode = false;
char *device_name = "/dev/ttyS2";
baudrate = 115200;
//! Time constant
float dt = 0.005f;
/* output euler angles */
@@ -321,6 +397,34 @@ const unsigned int loop_interval_alarm = 6500; // loop interval in microseconds
float gyro[3] = {0.0f, 0.0f, 0.0f};
float mag[3] = {0.0f, 0.0f, 0.0f};
/* work around some stupidity in task_create's argv handling */
argc -= 2;
argv += 2;
//! -d <device_name>, default : /dev/ttyS2
//! -b <baud_rate>, default : 115200
while ((ch = getopt(argc,argv,"d:b:")) != EOF){
switch(ch){
case 'b':
baudrate = strtoul(optarg, NULL, 10);
if(baudrate == 0)
printf("invalid baud rate '%s'",optarg);
break;
case 'd':
device_name = optarg;
debug_mode = true;
break;
default:
usage("invalid argument");
}
}
if(debug_mode){
uart = open_uart(baudrate, device_name, &uart_config_original, &usb_uart);
if (uart < 0)
printf("could not open %s", device_name);
}
// print text
printf("Nonlinear SO3 Attitude Estimator initialized..\n\n");
fflush(stdout);
@@ -554,9 +658,9 @@ const unsigned int loop_interval_alarm = 6500; // loop interval in microseconds
}
*/
euler[0] = atan2f(2*(q0*q1+q2*q3),1-2*(q1*q1+q2*q2));
euler[1] = asinf(2*(q0*q2-q3*q1));
euler[2] = atan2f(2*(q0*q3+q1*q2),1-2*(q2*q2+q3*q3));
euler[2] = atan2f(2*(q1*q2-q0*q3),2*(q0*q0+q1*q1)-1);
euler[1]= -asinf(2*(q1*q3+q0*q2));
euler[0] = atan2f(2*(q2*q3-q0*q1),2*(q0*q0+q3*q3)-1);
/* swap values for next iteration, check for fatal inputs */
@@ -607,7 +711,18 @@ const unsigned int loop_interval_alarm = 6500; // loop interval in microseconds
}
perf_end(so3_comp_loop_perf);
}
if(debug_mode)
{
float quat[4];
quat[0] = q0;
quat[1] = q1;
quat[2] = q2;
quat[3] = q3;
send_uart_float_arr(quat,4);
send_uart_byte('\n');
}
}// else
}
}
@@ -616,5 +731,9 @@ const unsigned int loop_interval_alarm = 6500; // loop interval in microseconds
thread_running = false;
/* Reset the UART flags to original state */
if (!usb_uart)
tcsetattr(uart, TCSANOW, &uart_config_original);
return 0;
}