Use new FlixPeriph library with ICM-20948 support

README.md

@@ -53,7 +53,7 @@ See [instructions on running the simulation](docs/build.md).
 |Type|Part|Image|Quantity|
 |-|-|:-:|:-:|
 |Microcontroller board|ESP32 Mini|<img src="docs/img/esp32.jpg" width=100>|1|
-|IMU and barometer² board|GY-91 (or other MPU-9250/MPU-6500 board)|<img src="docs/img/gy-91.jpg" width=100>|1|
+|IMU (and barometer²) board|GY‑91 (or other MPU‑9250/MPU‑6500 board), ICM‑20948³|<img src="docs/img/gy-91.jpg" width=90 align=center><img src="docs/img/icm-20948.jpg" width=100>|1|
 |Motor|8520 3.7V brushed motor (**shaft 0.8mm!**)|<img src="docs/img/motor.jpeg" width=100>|4|
 |Propeller|Hubsan 55 mm|<img src="docs/img/prop.jpg" width=100>|4|
 |MOSFET (transistor)|100N03A or [analog](https://t.me/opensourcequadcopter/33)|<img src="docs/img/100n03a.jpg" width=100>|4|
@@ -65,13 +65,14 @@ See [instructions on running the simulation](docs/build.md).
 |Frame bottom part|3D printed:<br>[`flix-frame.stl`](docs/assets/flix-frame.stl) [`flix-frame.step`](docs/assets/flix-frame.step)|<img src="docs/img/frame1.jpg" width=100>|1|
 |Frame top part|3D printed:<br>[`esp32-holder.stl`](docs/assets/esp32-holder.stl) [`esp32-holder.step`](docs/assets/esp32-holder.step)|<img src="docs/img/esp32-holder.jpg" width=100>|1|
 |Washer for IMU board mounting|3D printed:<br>[`washer-m3.stl`](docs/assets/washer-m3.stl) [`washer-m3.step`](docs/assets/washer-m3.step)|<img src="docs/img/washer-m3.jpg" width=100>|1|
-|*RC transmitter (optional)*|*KINGKONG TINY X8 or other³*|<img src="docs/img/tx.jpg" width=100>|1|
+|*RC transmitter (optional)*|*KINGKONG TINY X8 or other⁴*|<img src="docs/img/tx.jpg" width=100>|1|
-|*RC receiver (optional)*|*DF500 or other³*|<img src="docs/img/rx.jpg" width=100>|1|
+|*RC receiver (optional)*|*DF500 or other⁴*|<img src="docs/img/rx.jpg" width=100>|1|
 |Wires|28 AWG recommended|<img src="docs/img/wire-28awg.jpg" width=100>||
 |Tape, double-sided tape||||
 
 *² — barometer is not used for now.*<br>
-*³ — you may use any transmitter-receiver pair with SBUS interface.*
+*³ — change `MPU9250` to `ICM20948` in `imu.ino` file if using ICM-20948 board.*<br>
+*⁴ — you may use any transmitter-receiver pair with SBUS interface.*
 
 Tools required for assembly:
 
@@ -127,19 +128,19 @@ Complete diagram is Work-in-Progress.
   |-|-|
   |GND|GND|
   |VIN|VC (or 3.3V depending on the receiver)|
-  |Signal|GPIO4⁴|
+  |Signal|GPIO4⁵|
 
-*⁴ — UART2 RX pin was [changed](https://docs.espressif.com/projects/arduino-esp32/en/latest/migration_guides/2.x_to_3.0.html#id14) to GPIO4 in Arduino ESP32 core 3.0.*
+*⁵ — UART2 RX pin was [changed](https://docs.espressif.com/projects/arduino-esp32/en/latest/migration_guides/2.x_to_3.0.html#id14) to GPIO4 in Arduino ESP32 core 3.0.*
 
 ### IMU placement
 
-Required IMU orientation on the drone is **FLU** (Forward, Left, Up)⁵:
+Required IMU orientation on the drone is **FLU** (Forward, Left, Up)⁶:
 
 <img src="docs/img/flu.svg" width=400 alt="GY-91 axis">
 
 In case of using **FRD** orientation (Forward, Right, Down), use [the code for rotation](https://gist.github.com/okalachev/713db47e31bce643dbbc9539d166ce98).
 
-*⁵ — This X/Y/Z IMU axis orientation is used in the Flix IMU library, internal accel/gyro/mag axes differ.*
+*⁶ — This X/Y/Z IMU axis orientation is used in the Flix IMU library, internal accel/gyro/mag axes differ.*
 
 ## Version 0
 

docs/troubleshooting.md

@@ -13,19 +13,20 @@ Do the following:
 
 * **Check the battery voltage**. Use a multimeter to measure the battery voltage. It should be in range of 3.7-4.2 V.
 * **Check if there are some startup errors**. Connect the ESP32 to the computer and check the Serial Monitor output. Use the Reset button to make sure you see the whole ESP32 output.
+* **Make sure correct IMU model is chosen**. If using ICM-20948 board, change `MPU9250` to `ICM20948` everywhere in the `imu.ino` file.
 * **Check if the CLI is working**. Perform `help` command in Serial Monitor. You should see the list of available commands.
-* **Check the motors**. Perform the following commands using Serial Monitor:
-  * `mfr` — should rotate front right motor (counter-clockwise).
-  * `mfl` — should rotate front left motor (clockwise).
-  * `mrl` — should rotate rear left motor (counter-clockwise).
-  * `mrr` — should rotate rear right motor (clockwise).
-* **Calibrate the RC** if you use it. Perform `rc` command and put the results to `rc.ino` file.
-* **Check the RC data** if you use it. Use `rc` command, `Control` should show correct values between -1 and 1, and between 0 and 1 for the throttle.
 * **Configure QGroundControl correctly before connecting to the drone** if you use it to control the drone. Go to the settings and enable *Virtual Joystick*. *Auto-Center Throttle* setting **should be disabled**.
 * **Make sure you're not moving the drone several seconds after the power on**. The drone calibrates its gyroscope on the start so it should stay still for a while.
 * **Check the IMU sample rate**. Perform `imu` command. The `rate` field should be about 1000 (Hz).
 * **Check the IMU data**. Perform `imu` command, check raw accelerometer and gyro output. The output should change as you move the drone.
 * **Calibrate the accelerometer.** if is wasn't done before. Perform `ca` command and put the results to `imu.ino` file.
 * **Check the attitude estimation**. Connect to the drone using QGroundControl. Rotate the drone in different orientations and check if the attitude estimation shown in QGroundControl is correct.
+* * **Check the motors**. Perform the following commands using Serial Monitor:
+  * `mfr` — should rotate front right motor (counter-clockwise).
+  * `mfl` — should rotate front left motor (clockwise).
+  * `mrl` — should rotate rear left motor (counter-clockwise).
+  * `mrr` — should rotate rear right motor (clockwise).
+* **Calibrate the RC** if you use it. Perform `rc` command and put the results to `rc.ino` file.
+* **Check the RC data** if you use it. Use `rc` command, `Control` should show correct values between -1 and 1, and between 0 and 1 for the throttle.
 * **Check the IMU output using QGroundControl**. Connect to the drone using QGroundControl on your computer. Go to the *Analyze* tab, *MAVLINK Inspector*. Plot the data from the `SCALED_IMU` message. The gyroscope and accelerometer data should change according to the drone movement.
 * **Check the gyroscope only attitude estimation**. Comment out `applyAcc();` line in `estimate.ino` and check if the attitude estimation in QGroundControl. It should be stable, but only drift very slowly.

flix/imu.ino

@@ -34,8 +34,8 @@ void setupIMU() {
 void configureIMU() {
 	IMU.setAccelRange(IMU.ACCEL_RANGE_4G);
 	IMU.setGyroRange(IMU.GYRO_RANGE_2000DPS);
-	IMU.setDlpfBandwidth(IMU.DLPF_BANDWIDTH_184HZ);
+	IMU.setDLPF(IMU.DLPF_MAX);
-	IMU.setSrd(0); // set sample rate to 1000 Hz
+	IMU.setRate(IMU.RATE_1KHZ_APPROX);
 }
 
 void readIMU() {
@@ -67,8 +67,6 @@ void calibrateGyro() {
 void calibrateAccel() {
 	Serial.println("Calibrating accelerometer");
 	IMU.setAccelRange(IMU.ACCEL_RANGE_2G); // the most sensitive mode
-	IMU.setDlpfBandwidth(IMU.DLPF_BANDWIDTH_20HZ);
-	IMU.setSrd(19);
 
 	Serial.setTimeout(60000);
 	Serial.print("Place level [enter] "); Serial.readStringUntil('\n');
@@ -89,7 +87,7 @@ void calibrateAccel() {
 }
 
 void calibrateAccelOnce() {
-	const int samples = 100;
+	const int samples = 1000;
 	static Vector accMax(-INFINITY, -INFINITY, -INFINITY);
 	static Vector accMin(INFINITY, INFINITY, INFINITY);
 
@@ -125,6 +123,6 @@ void printIMUCal() {
 }
 
 void printIMUInfo() {
-	Serial.printf("type: %s\n", IMU.getType());
+	Serial.printf("model: %s\n", IMU.getModel());
 	Serial.printf("who am I: 0x%02X\n", IMU.whoAmI());
 }