WebSVN - FlightCtrl - Diff - Rev 2035 and 2049 - /branches/dongfang_FC

 #define _ANALOG_H
 #include <inttypes.h>
 #include "configuration.h"
-/*
- * How much low pass filtering to apply for gyro_PID.
- * 0=illegal, 1=no filtering, 2=50% last value + 50% new value, 3=67% last value + 33 % new value etc...
- * Temporarily replaced by userparam-configurable variable.
- */
-// #define GYROS_PID_FILTER 1
-/*
- * How much low pass filtering to apply for gyro_ATT.
- * 0=illegal, 1=no filtering, 2=50% last value + 50% new value, 3=67% last value + 33 % new value etc...
- * Temporarily replaced by userparam-configurable variable.
- */
-// #define GYROS_ATT_FILTER 1
-// #define ACC_FILTER 4
 /*
  About setting constants for different gyros:
  Main parameters are positive directions and voltage/angular speed gain.
  The "Positive direction" is the rotation direction around an axis where
  the corresponding gyro outputs a voltage > the no-rotation voltage.
  - Left hand side down for roll
  - Clockwise seen from above for yaw.
  Setting gyro gain correctly: All sensor measurements in analog.c take
  place in a cycle, each cycle comprising all sensors. Some sensors are
- sampled more than ones, and the results added. The pitch and roll gyros
- are sampled 4 times and the yaw gyro 2 times in the original H&I V0.74
- code.
+ sampled more than once (oversampled), and the results added.
  In the H&I code, the results for pitch and roll are multiplied by 2 (FC1.0)
  or 4 (other versions), offset to zero, low pass filtered and then assigned
- to the "HiResXXXX" and "AdWertXXXXFilter" variables, where XXXX is nick or
- roll.
- So:
+ to the "HiResXXXX" and "AdWertXXXXFilter" variables, where XXXX is nick or
- gyro = V * (ADCValue1 + ADCValue2 + ADCValue3 + ADCValue4),
- where V is 2 for FC1.0 and 4 for all others.
+ roll. The factor 2 or 4 or whatever is called GYRO_FACTOR_PITCHROLL here.
+*/
- Assuming constant ADCValue, in the H&I code:
- gyro = I * ADCValue.
+#define GYRO_FACTOR_PITCHROLL 1
- where I is 8 for FC1.0 and 16 for all others.
 /*
- The relation between rotation rate and ADCValue:
+ GYRO_HW_FACTOR is the relation between rotation rate and ADCValue:
  ADCValue [units] =
  rotational speed [deg/s] *
  gyro sensitivity [V / deg/s] *
  amplifier gain [units] *
-[units] /
-V full range [V]
+[units] /
- or: H is the number of steps the ADC value changes with,
+V full range [V]
  for a 1 deg/s change in rotational velocity:
- H = ADCValue [units] / rotation rate [deg/s] =
+ GYRO_HW_FACTOR is:
  gyro sensitivity [V / deg/s] *
  amplifier gain [units] *
 [units] /
 V full range [V]
  Examples:
- Examples:
+ FC1.3 has 0.67 mV/deg/s gyros and amplifiers with a gain of 5.7:
+ GYRO_HW_FACTOR = 0.00067 V / deg / s * 5.7 * 1024 / 3V = 1.304 units/(deg/s).
  FC1.3 has 0.67 mV/deg/s gyros and amplifiers with a gain of 5.7:
- H = 0.00067 V / deg / s * 5.7 * 1024 / 3V = 1.304 units/(deg/s).
+ FC2.0 has 6*(3/5) mV/deg/s gyros (they are ratiometric) and no amplifiers:
- FC2.0 has 6*(3/5) mV/deg/s gyros (they are ratiometric) and no amplifiers:
+ GYRO_HW_FACTOR = 0.006 V / deg / s * 1 * 1024 * 3V / (3V * 5V) = 1.2288 units/(deg/s).
  H = 0.006 V / deg / s * 1 * 1024 * 3V / (3V * 5V) = 1.2288 units/(deg/s).
  My InvenSense copter has 2mV/deg/s gyros and no amplifiers:
- H = 0.002 V / deg / s * 1 * 1024 / 3V = 0.6827 units/(deg/s)
+ GYRO_HW_FACTOR = 0.002 V / deg / s * 1 * 1024 / 3V = 0.6827 units/(deg/s)
  (only about half as sensitive as V1.3. But it will take about twice the
- rotation rate!)
- All together: gyro = I * H * rotation rate [units / (deg/s)].
- */
-/*
- * A factor that the raw gyro values are multiplied by,
- * before being filtered and passed to the attitude module.
- * A value of 1 would cause a little bit of loss of precision in the
- * filtering (on the other hand the values are so noisy in flight that
- * it will not really matter - but when testing on the desk it might be
- * noticeable). 4 is fine for the default filtering.
+ rotation rate!)
  * Experiment: Set it to 1.
- */
+ GYRO_HW_FACTOR is given in the makefile.
-#define GYRO_FACTOR_PITCHROLL 1
+*/
 /*
- * How many samples are summed in one ADC loop, for pitch&roll and yaw,
+ * How many samples are added in one ADC loop, for pitch&roll and yaw,
  * respectively. This is = the number of occurences of each channel in the
  * channelsForStates array in analog.c.
- */
-#define GYRO_OVERSAMPLING_PITCHROLL 4
-#define GYRO_OVERSAMPLING_YAW 2
-#define ACC_OVERSAMPLING_XY 2
-#define ACC_OVERSAMPLING_Z 1
+ */
-/*
- Integration:
- The HiResXXXX values are divided by 8 (in H&I firmware) before integration.
- In the Killagreg rewrite of the H&I firmware, the factor 8 is called
- HIRES_GYRO_AMPLIFY. In this code, it is called HIRES_GYRO_INTEGRATION_FACTOR,
- and care has been taken that all other constants (gyro to degree factor, and
-degree flip-over detection limits) are corrected to it. Because the
- division by the constant takes place in the flight attitude code, the
- constant is there.
- The control loop executes at 488Hz, and for each iteration
- gyro_ATT[PITCH/ROLL] is added to gyroIntegral[PITCH/ROLL].
- Assuming a constant rotation rate v and a zero initial gyroIntegral
- (for this explanation), we get:
- gyroIntegral =
- N * gyro / HIRES_GYRO_INTEGRATION_FACTOR =
- N * I * H * v / HIRES_GYRO_INTEGRATION_FACTOR
- where N is the number of summations; N = t*488.
- For one degree of rotation: t*v = 1:
- gyroIntegralXXXX = t * 488 * I * H * 1/t = INTEGRATION_FREQUENCY * I * H / HIRES_GYRO_INTEGRATION_FACTOR.
+#define GYRO_OVERSAMPLING_PITCHROLL 4
+#define GYRO_OVERSAMPLING_YAW 2
 #define ACC_OVERSAMPLING_XY 2
- This number (INTEGRATION_FREQUENCY * I * H) is the integral-to-degree factor.
+#define ACC_OVERSAMPLING_Z 1
- Examples:
+/*
- FC1.3: I=4, H=1.304, HIRES_GYRO_INTEGRATION_FACTOR=1 --> integralDegreeFactor = 2545
- FC2.0: I=4, H=1.2288, HIRES_GYRO_INTEGRATION_FACTOR=1 --> integralDegreeFactor = 2399
- My InvenSense copter: HIRES_GYRO_INTEGRATION_FACTOR=4, H=0.6827 --> integralDegreeFactor = 1333
+ * The product of the 3 above constants. This represents the expected change in ADC value sums for 1 deg/s of rotation rate.
  */
 #define GYRO_RATE_FACTOR_PITCHROLL (GYRO_HW_FACTOR * GYRO_OVERSAMPLING_PITCHROLL * GYRO_FACTOR_PITCHROLL)
-/*
+#define GYRO_RATE_FACTOR_YAW (GYRO_HW_FACTOR * GYRO_OVERSAMPLING_YAW)

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(root)/branches/dongfang_FC_rewrite/analog.h - Rev 2035 → 2049