}
real g_count = 264.8;
+#real g_count = 262;
+#real g_count = 400;
+int g_base = 15735;
+
real
count_to_g(real count)
{
- return (15792 + g_count - count) / g_count;
+ return (g_base + g_count - count) / g_count;
}
real base_alt = 0;
real gaussian(real x) = exp(-(x**2)/2) / sqrt(2 * pi);
-load "/usr/share/nickle/examples/kaiser.5c"
+load "filter.5c"
real[...] convolve(real[...] d, real[...] e) {
real sample(n) = n < 0 ? d[0] : n >= dim(d) ? d[dim(d)-1] : d[n];
real sum(real[...] x) { real s = 0; for(int i = 0; i < dim(x); i++) s += x[i]; return s; }
-real[...] filter(real[...] d, int half_width) {
+real[...] kaiser_filter(real[...] d, int half_width) {
# real[half_width * 2 + 1] fir = { [n] = sinc(2 * pi * n / (2 * half_width)) };
real M = half_width * 2 + 1;
real[M] fir = { [n] = kaiser(n, M, 8) };
return convolve(d, fir);
}
+int[...] int_filter(int[...] d, int shift) {
+ /* Emulate the exponential IIR filter used in the TeleMetrum flight
+ software */
+
+ int v = d[0];
+ int n;
+ int[dim(d)] ret;
+
+ for (n = 0; n < dim(d); n++) {
+ v -= (v + (1 << (shift - 1))) >> shift;
+ v += (d[n] + (1 << (shift - 1))) >> shift;
+ ret[n] = v;
+ }
+ return ret;
+}
+
real gravity = 9.80665;
-real[...] pressure_value, accelerometer_value;
+int[...] pressure_value, accelerometer_value;
real[...] clock;
-void readsamples(file in) {
+void readsamples_log(file in) {
setdim(pressure_value, 0);
setdim(accelerometer_value, 0);
while (!File::end(in)) {
flight_record r = read_record(in);
+ if (r.type == 'F') {
+ g_base = r.a;
+ }
if (r.type == 'A') {
clock[dim(clock)] = r.time / 100;
pressure_value[dim(pressure_value)] = r.b;
}
}
-readsamples(stdin);
+typedef struct {
+ int time;
+ int accel;
+ int pressure;
+ string state;
+} telem_record;
-int size = dim(accelerometer_value);
-real[size] accelerometer = { [n] = gravity * (count_to_g(accelerometer_value[n]) - 1.0) };
-real[size] barometer = { [n] = pressure_to_altitude(count_to_kPa(pressure_value[n] / 16) * 1000) };
-real[size] filtered_accelerometer = filter(accelerometer, 8);
-real[size] filtered_barometer = filter(barometer, 128);
-
-real[...] integrate(real[...] d) {
- real[dim(d)] ret;
- for (int i = 0; i < dim(ret); i++)
- ret[i] = i == 0 ? 0 : ret[i-1] + (d[i-1] + d[i]) / 2 * (clock[i] - clock[i-1]);
- return ret;
+autoimport String;
+
+telem_record read_telem(file in) {
+ string[*] r = wordsplit(chomp(fgets(in)), " ");
+ static int line = 0;
+
+ line++;
+ if (dim(r) < 15) {
+ printf ("invalid record line %d\n", line);
+ return read_telem(in);
+ }
+ return (telem_record) {
+ .time = string_to_integer(r[10]),
+ .accel = string_to_integer(r[12]),
+ .pressure = string_to_integer(r[14]),
+ .state = r[9]
+ };
+}
+
+void readsamples_telem(file in) {
+ telem_record[...] telem;
+
+ setdim(telem, 0);
+
+ setdim(clock, 0);
+ setdim(pressure_value, 0);
+ setdim(accelerometer_value, 0);
+ real clock_bias = 0;
+
+ telem_record[...] save = {};
+
+ setdim(save, 0);
+ while (!File::end(in)) {
+ save[dim(save)] = read_telem(in);
+ if (save[dim(save)-1].state == "boost")
+ break;
+ }
+ int start = dim(save) - 4;
+
+ int accel_total = 0;
+ for (int i = 0; i < start; i++)
+ accel_total += save[i].accel;
+ g_base = accel_total // start;
+
+ for (int i = start; i < dim(save); i++)
+ telem[dim(telem)] = save[i];
+
+ while (!File::end(in)) {
+ int n = dim(telem);
+ telem[n] = read_telem(in);
+ telem[n].time += clock_bias;
+ if (n > 0 && telem[n].time < telem[n-1].time) {
+ clock_bias += 65536;
+ telem[n].time += 65536;
+ }
+ }
+ int clock_start = telem[0].time;
+ int clock_end = telem[dim(telem)-1].time;
+ int samples = clock_end - clock_start;
+
+ int j = 0;
+ for (int i = 0; i < samples; i++) {
+ clock[i] = i / 100;
+ pressure_value[i] = telem[j].pressure;
+ accelerometer_value[i] = telem[j].accel;
+ if (j < dim(telem)-1) {
+ int cur_time = clock_start + i;
+ if (cur_time - telem[j].time > telem[j+1].time - cur_time)
+ j++;
+ }
+ }
}
-real[...] differentiate(real[...] d) {
- real[dim(d)] ret;
- for (int i = 1; i < dim(ret); i++)
- ret[i] = (d[i] - d[i-1]) / (clock[i] - clock[i-1]);
- ret[0] = ret[1];
+readsamples_log(stdin);
+
+int[...] int_integrate(int[...] d, int base) {
+ int v = 0;
+ int[dim(d)] ret;
+
+ ret[0] = 0;
+ for (int i = 1; i < dim(d); i++)
+ ret[i] = (v += (d[i-1] + d[i] + 1) // 2);
return ret;
}
-real[size] accel_speed = integrate(filtered_accelerometer);
-real[size] accel_pos = integrate(accel_speed);
-real[size] baro_speed = differentiate(filtered_barometer);
-real[size] baro_accel = differentiate(baro_speed);
-
-for (int i = 0; i < size; i++)
- printf("%g %g %g %g %g %g %g %g %g\n",
- clock[i] - clock[0],
- filtered_barometer[i] - filtered_barometer[0], accel_pos[i],
- baro_speed[i], accel_speed[i],
- baro_accel[i], filtered_accelerometer[i],
- barometer[i] - barometer[0], accelerometer[i]);
+int[...] int_differentiate(int[...] d) {
+ return (int[dim(d)]) { [n] = n == 0 ? 0 : d[n] - d[n-1] };
+}
+
+int average(int[...] d, int n) {
+ int sum = 0;
+ for (int i = 0; i < n; i++)
+ sum += d[n];
+ return sum // n;
+}
+
+int[...] rebase(int[...] d, int m, int a) = (int[dim(d)]) { [n] = d[n] * m + a };
+
+int size = dim(accelerometer_value);
+
+real[...] do_low_pass(real[] data, real ωpass, real ωstop, real error) {
+ real[*] fir = low_pass_filter (ωpass, ωstop, error);
+ File::fprintf (stderr, "low pass filter is %d long\n", dim(fir));
+ return convolve(data, fir);
+}
+
+if (false) {
+ accelerometer_value = rebase(accelerometer_value, -1, g_base);
+ int accel_i0_base = average(accelerometer_value, 30);
+ int[size] pres_d0 = int_filter(pressure_value, 4);
+ int[size] accel_i0 = int_filter(accelerometer_value, 4);
+ int[size] pres_d1 = int_filter(int_differentiate(pres_d0), 4);
+ int[size] accel_i1 = int_integrate(accelerometer_value, accel_i0_base);
+ int[size] pres_d2 = int_filter(int_differentiate(pres_d1), 4);
+ int[size] accel_i2 = int_integrate(accel_i1, 0);
+
+ real count_to_altitude(int count) = pressure_to_altitude(count_to_kPa(count / 16) * 1000);
+
+ for (int i = 0; i < size; i++)
+ printf("%g %g %g %g %g %g %g %g %g\n",
+ clock[i] - clock[0],
+ count_to_altitude(pres_d0[i]) - count_to_altitude(pres_d0[0]), accel_i2[i] / 10000 / g_count * gravity,
+ pres_d1[i] * 100, accel_i1[i] / 100 / g_count * gravity,
+ pres_d2[i] * 10000, accel_i0[i] / g_count * gravity,
+ count_to_altitude(pressure_value[i]) -
+ count_to_altitude(pressure_value[0]), accelerometer_value[i]
+ / g_count * gravity);
+
+} else {
+ real[size] accelerometer = { [n] = gravity * (count_to_g(accelerometer_value[n]) - 1.0) };
+ real[size] barometer = { [n] = pressure_to_altitude(count_to_kPa(pressure_value[n] / 16) * 1000) };
+ real[size] filtered_accelerometer = do_low_pass(accelerometer,
+ 2 * π * 5/100,
+ 2 * π * 8/100,
+ 1e-8);
+ real[size] filtered_barometer = do_low_pass(barometer,
+ 2 * π * .5 / 100,
+ 2 * π * 1 / 100,
+ 1e-8);
+
+ real[...] integrate(real[...] d) {
+ real[dim(d)] ret;
+ for (int i = 0; i < dim(ret); i++)
+ ret[i] = i == 0 ? 0 : ret[i-1] + (d[i-1] + d[i]) / 2 * (clock[i] - clock[i-1]);
+ return ret;
+ }
+
+ real[...] differentiate(real[...] d) {
+ real[dim(d)] ret;
+ for (int i = 1; i < dim(ret); i++)
+ ret[i] = (d[i] - d[i-1]) / (clock[i] - clock[i-1]);
+ ret[0] = ret[1];
+ return ret;
+ }
+
+ real[size] accel_speed = integrate(accelerometer);
+ real[size] accel_pos = integrate(accel_speed);
+ real[size] baro_speed = differentiate(filtered_barometer);
+ real[size] baro_accel = differentiate(baro_speed);
+
+ printf("%7s %12s %12s %12s %12s %12s %12s %12s %12s\n",
+ "time",
+ "height(baro)",
+ "height(accel)",
+ "speed(baro)",
+ "speed(accel)",
+ "accel(baro)",
+ "accel(accel)",
+ "raw(baro)",
+ "raw(accel)");
+ for (int i = 0; i < size; i++)
+ printf("%7.2f %12.6f %12.6f %12.6f %12.6f %12.6f %12.6f %12.6f %12.6f\n",
+ clock[i] - clock[0],
+ filtered_barometer[i] - filtered_barometer[0], accel_pos[i],
+ baro_speed[i], accel_speed[i],
+ baro_accel[i], filtered_accelerometer[i],
+ barometer[i] - barometer[0], accelerometer[i]);
+}
projects / fw / tmflights / blobdiff