Rename lpf.h to filter.h

To implement more filters (like notch) potentially.

.github/workflows/build.yml

@@ -10,23 +10,31 @@ on:
 jobs:
   build_linux:
     runs-on: ubuntu-latest
+    env:
+        ARDUINO_SKETCH_ALWAYS_EXPORT_BINARIES: 1
     steps:
     - uses: actions/checkout@v4
     - name: Install Arduino CLI
       run: curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | BINDIR=/usr/local/bin sh
-    - name: Build firmware
+    - name: Build firmware for ESP32
-      env:
-        ARDUINO_SKETCH_ALWAYS_EXPORT_BINARIES: 1
       run: make
+    - name: Build firmware for ESP32-C3
+      run: make BOARD=esp32:esp32:esp32c3
+    - name: Build firmware for ESP32-S3
+      run: make BOARD=esp32:esp32:esp32s3:CDCOnBoot=cdc
+    - name: Build firmware for ESP32-S3 with QSPI PSRAM
+      run: make BOARD=esp32:esp32:esp32s3:CDCOnBoot=cdc,PSRAM=enabled EXTRA=--output-dir=flix/build/esp32.esp32.esp32s3.qspi
+    - name: Build firmware for ESP32-S3 with OPI PSRAM
+      run: make BOARD=esp32:esp32:esp32s3:CDCOnBoot=cdc,PSRAM=opi EXTRA=--output-dir=flix/build/esp32.esp32.esp32s3.opi
+    - name: Build firmware for Flix2
+      run: make BOARD=esp32:esp32:esp32s3:FlashSize=4M,CDCOnBoot=cdc,PSRAM=opi EXTRA='--build-property "compiler.cpp.extra_flags=-DFLIX2" --output-dir=flix/build/esp32.esp32.flix2'
     - name: Upload binaries
       uses: actions/upload-artifact@v4
       with:
         name: firmware-binary
         path: flix/build
-    - name: Build firmware for ESP32-C3
+    - name: Build espnow-proxy
-      run: make BOARD=esp32:esp32:esp32c3
+      run: arduino-cli compile --fqbn esp32:esp32:esp32 tools/espnow-proxy
-    - name: Build firmware for ESP32-S3
-      run: make BOARD=esp32:esp32:esp32s3
     - name: Check c_cpp_properties.json
       run: tools/check_c_cpp_properties.py
 
@@ -64,7 +72,7 @@ jobs:
         apt-get update
         DEBIAN_FRONTEND=noninteractive apt-get install -y curl wget build-essential cmake g++ pkg-config gnupg2 lsb-release sudo
     - name: Install Arduino CLI
-      uses: arduino/setup-arduino-cli@v1.1.1
+      run: curl -fsSL https://raw.githubusercontent.com/arduino/arduino-cli/master/install.sh | BINDIR=/usr/local/bin sh
     - uses: actions/checkout@v4
     - name: Install Gazebo
       run: |

.github/workflows/docs.yml

@@ -8,6 +8,7 @@ on:
 
 permissions:
   contents: read
+  actions: read
   pages: write
   id-token: write
 
@@ -30,6 +31,38 @@ jobs:
       run: cargo install mdbook --vers 0.4.43 --locked
     - name: Build book
       run: cd docs && mdbook build
+    - name: Wait for Build to complete
+      uses: lewagon/wait-on-check-action@v1.9.1
+      with:
+        ref: ${{ github.sha }}
+        check-name: build_linux
+        repo-token: ${{ secrets.GITHUB_TOKEN }}
+        wait-interval: 30
+    - name: Find firmware binaries
+      id: build_run
+      run: |
+        RUN_ID=$(gh api "repos/${{ github.repository }}/actions/workflows/build.yml/runs?head_sha=${{ github.sha }}&per_page=1" --jq '.workflow_runs[0].id')
+        echo "id=$RUN_ID" >> $GITHUB_OUTPUT
+      env:
+        GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+    - name: Download firmware binaries
+      uses: actions/download-artifact@v4
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
+        repository: ${{ github.repository }}
+        run-id: ${{ steps.build_run.outputs.id }}
+        name: firmware-binary
+        path: docs/build
+    - name: Create shortcuts for firmware binaries
+      working-directory: docs/build
+      run: |
+        for FQBN in esp32.esp32.*; do
+          zip -r $FQBN.zip $FQBN
+          BOARD="${FQBN#esp32.esp32.}"
+          ln -s "$FQBN/flix.ino.merged.bin" "flix.$BOARD.merged.bin"
+          ln -s "$FQBN/flix.ino.bin" "flix.$BOARD.bin"
+          ln -s "$FQBN/flix.ino.bootloader.bin" "flix.$BOARD.bootloader.bin"
+        done
     - name: Upload artifact
       uses: actions/upload-pages-artifact@v3
       with:

Makefile

@@ -1,10 +1,10 @@
-BOARD = esp32:esp32:d1_mini32:DebugLevel=error
+BOARD = esp32:esp32:esp32
 PORT := $(strip $(wildcard /dev/serial/by-id/usb-Silicon_Labs_CP21* /dev/serial/by-id/usb-1a86_USB_Single_Serial_* /dev/cu.usbserial-* /dev/cu.usbmodem*))
 
 export ARDUINO_NETWORK_CONNECTION_TIMEOUT := 1h
 
 build: .core .libs
-	arduino-cli compile --fqbn $(BOARD) flix
+	arduino-cli compile --fqbn $(BOARD) --build-property "build.core_debug_level=1" flix $(EXTRA)
 
 upload: build
 	arduino-cli upload --fqbn $(BOARD) -p "$(PORT)" flix

README.md

@@ -55,6 +55,12 @@ Outdoor flights demo video of the current prototype:
 
 <a href="https://youtu.be/KXlNmvUTi4g"><img width=300 src="https://i3.ytimg.com/vi/KXlNmvUTi4g/maxresdefault.jpg"></a>
 
+### Position control
+
+The position control feature is in development. RoboCamp 2026 demo (using an overhead camera, [sources](https://github.com/xTimop/flix-poscontrol/compare/robolager2026...xTimop:flix-poscontrol:poscontrol)):
+
+<a href="https://youtu.be/369Xowm4HcU"><img width=300 src="https://i3.ytimg.com/vi/369Xowm4HcU/maxresdefault.jpg"></a>
+
 ## Simulation
 
 The simulator is implemented using Gazebo and runs the original Arduino code:
@@ -84,7 +90,7 @@ Additional articles:
 |*Boost converter (optional, for more stable power supply)*|*5V output*|<img src="docs/img/buck-boost.jpg" width=100>|1|
 |Motor|8520 3.7V brushed motor.<br>Motor with exact 3.7V voltage is needed, not ranged working voltage (3.7V — 6V).<br>Make sure the motor shaft diameter and propeller hole diameter match!|<img src="docs/img/motor.jpeg" width=100>|4|
 |Propeller|55 mm or 65 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|
+|MOSFET (transistor)|UMW 100N03A or [analog](https://t.me/opensourcequadcopter/33).<br>Warning: don't use KIA 100N03A or other manufacturers, they might not work!|<img src="docs/img/100n03a.jpg" width=100>|4|
 |Pull-down resistor<br>Voltage measurement resistor|10 kΩ|<img src="docs/img/resistor10k.jpg" width=100>|6|
 |3.7V Li-Po battery|LW 952540 (or any compatible by the size).<br>Make sure the battery has enough discharge rate — 25C or more!|<img src="docs/img/battery.jpg" width=100>|1|
 |Battery connector cable|MX2.0 2P female|<img src="docs/img/mx.png" width=100>|1|

docs/usage.md

@@ -1,20 +1,48 @@
 # Usage: build, setup and flight
 
-To fly Flix quadcopter, you need to build the firmware, upload it to the ESP32 board, and set up the drone for flight.
+To fly Flix quadcopter, you need to upload the firmware to the ESP32 board, and set up the drone for flight.
 
-To get the firmware sources, clone the repository using git:
+## Uploading the firmware
+
+You can either use the **prebuilt binaries** or **build the firmware** from sources — this will let you modify the firmware and add new features.
+
+### Prebuilt binaries (the easiest way)
+
+1. Download the latest firmware file using the following links:
+
+   <!-- markdownlint-disable MD044 -->
+   |Type|Boards|Link|
+   |-|-|-|
+   |ESP32|DevKit, D1 Mini|[`quadcopter.dev/flix.esp32.merged.bin`](https://quadcopter.dev/flix.esp32.merged.bin)|
+   |ESP32-S3|Most S3 based|[`quadcopter.dev/flix.esp32s3.merged.bin`](https://quadcopter.dev/flix.esp32s3.merged.bin)|
+   |ESP32-S3 (2MB PSRAM)|S3 Super Mini, S3 Zero (2MB PSRAM)|[`quadcopter.dev/flix.esp32s3.qspi.merged.bin`](https://quadcopter.dev/flix.esp32s3.qspi.merged.bin)|
+   |ESP32-S3 (8/16MB PSRAM)|S3 Zero (8MB PSRAM)|[`quadcopter.dev/flix.esp32s3.opi.merged.bin`](https://quadcopter.dev/flix.esp32s3.opi.merged.bin)|
+   |ESP32-C3|C3 Super Mini|[`quadcopter.dev/flix.esp32c3.merged.bin`](https://quadcopter.dev/flix.esp32c3.merged.bin)|
+   |Flix2|Flix2 board|[`quadcopter.dev/flix.flix2.merged.bin`](https://quadcopter.dev/flix.flix2.merged.bin)|
+   <!-- markdownlint-enable MD044 -->
+
+2. Flash your ESP32 board using [ESP32 Web Flasher](https://www.espboards.dev/tools/program/):
+
+   <img src="img/web-flasher.png" width="400">
+
+   * Connect the board to your computer, press *Connect to ESP*, choose the serial port.
+   * Go to the *Flash* tab.
+   * Choose the downloaded firmware file, set *Flash address* to *0* (important).
+   * Click *Program* button and wait until the process is finished.
+
+### Building from sources (flexible)
+
+You can build and upload the firmware using either **Arduino IDE** (easier for beginners) or **command line**.
+
+Get the sources using git:
 
 ```bash
 git clone https://github.com/okalachev/flix.git && cd flix
 ```
 
-Beginners can [download the source code as a ZIP archive](https://github.com/okalachev/flix/archive/refs/heads/master.zip).
+Beginners can [download the sources as a ZIP archive](https://github.com/okalachev/flix/archive/refs/heads/master.zip).
 
-## Building the firmware
+#### Arduino IDE (Windows, Linux, macOS)
-
-You can build and upload the firmware using either **Arduino IDE** (easier for beginners) or **command line**.
-
-### Arduino IDE (Windows, Linux, macOS)
 
 <img src="img/arduino-ide.png" width="400" alt="Flix firmware open in Arduino IDE">
 
@@ -25,11 +53,11 @@ You can build and upload the firmware using either **Arduino IDE** (easier for b
    * `FlixPeriph`, the latest version.
    * `MAVLink`, version 2.0.25.
 5. Open the `flix/flix.ino` sketch from downloaded firmware sources in Arduino IDE.
-6. Connect your ESP32 board to the computer and choose correct board type in Arduino IDE (*WEMOS D1 MINI ESP32* for ESP32 Mini) and the port.
+6. Connect your ESP32 board to the computer and choose correct board type in Arduino IDE (*WEMOS D1 MINI ESP32* for ESP32 Mini, *ESP32S3 Dev Module* for ESP32-S3 Super Mini) and the port.
 7. Set *Tools* ⇒ *Core Debug Level* to *Error* to see the errors in the serial console. Set *Tools* ⇒ *USB CDC on Boot* to *Enabled* for ESP32-S3/ESP32-C3 boards.
 8. [Build and upload](https://docs.arduino.cc/software/ide-v2/tutorials/getting-started/ide-v2-uploading-a-sketch) the firmware using Arduino IDE.
 
-### Command line (Windows, Linux, macOS)
+#### Command line (Windows, Linux, macOS)
 
 1. [Install Arduino CLI](https://arduino.github.io/arduino-cli/installation/).
 
@@ -61,7 +89,7 @@ You can build and upload the firmware using either **Arduino IDE** (easier for b
    For ESP32-S3/ESP32-C3 boards, set the appropriate [FQBN](https://docs.arduino.cc/arduino-cli/FAQ/#whats-the-fqbn-string) using `BOARD` parameter:
 
    ```bash
-   make BOARD=esp32:esp32:esp32s3:DebugLevel=error,FlashSize=4M,CDCOnBoot=cdc upload
+   make BOARD=esp32:esp32:esp32s3:FlashSize=4M,CDCOnBoot=cdc upload
    ```
 
 See other available Make commands in [Makefile](../Makefile).
@@ -71,15 +99,6 @@ See other available Make commands in [Makefile](../Makefile).
 
 ## Before first flight
 
-### Choose the IMU model
-
-In case if using different IMU model than MPU9250, change `imu` variable declaration in the `imu.ino`:
-
-```cpp
-ICM20948 imu(SPI);  // For ICM-20948
-MPU6050 imu(Wire);  // For MPU-6050
-```
-
 ### Connect using QGroundControl
 
 QGroundControl is a ground control station software that can be used to monitor and control the drone.
@@ -105,7 +124,7 @@ To access the console using serial port:
 To access the console using QGroundControl:
 
 1. Connect to the drone using QGroundControl app.
-2. Go to the QGroundControl menu ⇒ *Vehicle Setup* ⇒ *Analyze Tools* ⇒ *MAVLink Console*.
+2. Go to the QGroundControl menu ⇒ *Analyze Tools* ⇒ *MAVLink Console*.
 
 <img src="img/cli.png" width="400">
 
@@ -120,6 +139,17 @@ The drone is configured using parameters. To access and modify them, go to the Q
 
 You can also work with parameters using `p` command in the console. Parameter names are case-insensitive.
 
+### Configure the IMU
+
+1. Configure the following parameters for the IMU:
+   * `IMU_MODEL` — IMU model (1 for MPU-9250/MPU-6500, 2 for ICM-20948, 3 for MPU-6050, 4 for ICM-40609-D).
+   * `IMU_BUS` — communication bus (0 for SPI, 1 for I²C).
+   * `IMU_PIN_SCK`, `IMU_PIN_MISO`, `IMU_PIN_MOSI`, `IMU_PIN_CS` — SPI pin numbers.
+   * `IMU_PIN_SCL`, `IMU_PIN_SDA` — I²C pin numbers.
+   * `IMU_PIN_INT` — IMU data ready pin number (-1 if not used).
+2. Reboot the drone.
+3. Check the IMU is working using `imu` command in the console (should print `status: OK`).
+
 ### Define IMU orientation
 
 The IMU orientation (relative to the drone's axes) is defined using the parameters: `IMU_ROT_ROLL`, `IMU_ROT_PITCH`, and `IMU_ROT_YAW`.
@@ -148,9 +178,9 @@ Before flight you need to calibrate the accelerometer:
 
 If using non-default motor pins, set the pin numbers using the parameters: `MOTOR_PIN_FL`, `MOTOR_PIN_FR`, `MOTOR_PIN_RL`, `MOTOR_PIN_RR` (front-left, front-right, rear-left, rear-right respectively).
 
-Certain ESP32 models (such as ESP32-S3 and ESP32-C3) support a lower maximum PWM frequency; on these boards the parameter `MOT_PWM_FREQ` should be set to 38000 Hz.
+#### Brushless motors
 
-If using brushless motors and ESCs:
+If using brushless motors with ESCs:
 
 1. Set the appropriate PWM using the parameters: `MOT_PWM_STOP`, `MOT_PWM_MIN`, and `MOT_PWM_MAX` (1000, 1000, and 2000 is typical).
 2. Decrease the PWM frequency using the `MOT_PWM_FREQ` parameter (400 is typical).
@@ -158,7 +188,7 @@ If using brushless motors and ESCs:
 > [!CAUTION]
 > **Remove the props when configuring the motors!** If improperly configured, you may not be able to stop them.
 
-### Battery voltage monitoring
+### Battery voltage monitoring (optional)
 
 ESP32 ADC can measure only up to 3.3 V, so you need to use a voltage divider to monitor the battery voltage. To enable voltage measurement, set the following parameters:
 
@@ -198,7 +228,7 @@ After this setup, you should see the battery voltage in QGroundControl top panel
 
 ## Setup remote control
 
-There are several ways to control the drone's flight: using **smartphone** (Wi-Fi), using **SBUS remote control**, or using **USB remote control** (Wi-Fi).
+There are several ways to control the drone's flight: using **smartphone** (Wi-Fi), using **SBUS remote control**, or using **USB remote control** (Wi-Fi/ESP-NOW).
 
 ### Control with a smartphone
 
@@ -243,7 +273,7 @@ If your drone doesn't have RC receiver installed, you can use USB remote control
 3. Power up the drone.
 4. Connect your computer to the appeared `flix` Wi-Fi network (password: `flixwifi`).
 5. Launch QGroundControl app. It should connect and begin showing the drone's telemetry automatically.
-6. Go the the QGroundControl menu ⇒ *Vehicle Setup* ⇒ *Joystick*. Calibrate you USB remote control there.
+6. Go to the QGroundControl menu ⇒ *Vehicle Setup* ⇒ *Joystick*. Calibrate your USB remote control there.
 7. Use the USB remote control to fly the drone!
 
 ## Flight
@@ -333,13 +363,13 @@ To setup ESP-NOW communication:
 
 1. Flash the second ESP32 board with ESP-NOW proxy sketch: [`tools/espnow-proxy/espnow-proxy.ino`](../tools/espnow-proxy/espnow-proxy.ino). Use Arduino IDE or command line: `make upload_proxy`.
 
-2. Open Serial Monitor or use `make monitor` command. The ESP32 will print its MAC address and generated encryption key, for example:
+2. Open Serial Monitor in Arduino IDE or use `make monitor` command. The ESP32 will print its MAC address and generated encryption key, for example:
 
    ```
    espnow 7a:c8:e3:eb:bf:e9 &PiuSysxP9+$L&5E
    ```
 
-   Run this line as a console command on each drone you want to bind to this proxy board. [The maximum number](https://github.com/espressif/esp-idf/blob/e95cab4be8fd293e3f3323181e7a2280874da6f7/components/esp_wifi/include/esp_now.h#L32-L33) of simultaneously connected drones is 20 (unencrypted) io 6 (encrypted).
+   Run this line as a console command on each drone you want to bind to this proxy board. [The maximum number](https://github.com/espressif/esp-idf/blob/e95cab4be8fd293e3f3323181e7a2280874da6f7/components/esp_wifi/include/esp_now.h#L32-L33) of simultaneously connected drones is 20 (unencrypted) or 6 (encrypted).
 
 3. Set the `WIFI_MODE` parameter to `3` on the drone:
 
@@ -352,11 +382,14 @@ To setup ESP-NOW communication:
    * Type: Serial.
    * Serial Port: choose the port of the proxy ESP32 board, e. g. `/dev/cu.usbserial-0001`.
    * Baud Rate: 115200.
-5. Click *Save*. QGroundControl should connect to the drone using ESP-NOW and begin showing the telemetry.
+5. Click *Save*, click *Connect*. QGroundControl should connect to the drone using ESP-NOW and begin showing the telemetry.
+
+> [!TIP]
+> Make sure Arduino IDE is not running when using ESP-NOW proxy board, as it may block the serial port.
 
 ## Flight log
 
-After the flight, you can download the flight log for analysis wirelessly. Use the following command on your computer for that:
+After the flight, you can download the flight log wirelessly for analysis. Use the following command on your computer for that:
 
 ```bash
 make log

docs/user.md

@@ -4,6 +4,24 @@ This page contains user-built drones based on the Flix project. Publish your pro
 
 ---
 
+Author: [Oleg1405](https://t.me/Oleg1405).<br>
+Description: ESP32 Mini, MPU-6500 IMU, boost converter, BT2.0 power connector, 65 mm props, BetaFPV ELRS Lite Receiver, Radiomaster Pocket + Mavlink Joystick (Android) control.
+
+<img src="img/user/oleg1405/1.jpg" height=300>
+
+[Flight video](https://www.youtube.com/shorts/rbXV4sHbpso).
+
+---
+
+Author: Alican Erüst.<br>
+Description: QX95 mm frame, 55 mm propellers, 3.7 V 25C 1050 mAh LiPo battery, MPU6050 IMU, Logitech F310 gamepad controller, with a total quadcopter weight of 66 g.
+
+<img src="img/user/alicanerus/1.jpg" height=200> <img src="img/user/alicanerus/2.jpg" height=200> <img src="img/user/alicanerus/3.jpg" height=200>
+
+[Flight video](https://drive.google.com/file/d/1k0WeWTKnCAfaugkX7LcmNxsUuq79RL8Z/view?usp=sharing).
+
+---
+
 Author: [Неруш Михаил](https://t.me/NerushMV).<br>
 Description: custom frame made of 4 mm plywood, 8520 brushed motors, 75 mm propellers, MPU-6500. FlySky FS-i6X with ESP32-based adapter for ESP-NOW communication (using PPM output).<br>
 Sources and materials: [link](https://drive.google.com/drive/folders/1uWiDcuorLrtVs_IIR7Y13omij-7Q1nx8).

flix/cli.ino

@@ -51,13 +51,7 @@ const char* motd =
 "espnow <mac> [<key>] - configure ESP-NOW peer\n"
 "mot - show motor output\n"
 "log [dump] - print log header [and data]\n"
-"mfr, mfl, mrr, mrl - test motor (remove props)\n"
+"mfr/mfl/mrr/mrl [<thrust>] - test motor (remove props)\n"
-"log - show log info\n"
-"log header - show log header\n"
-"log reset - reset log\n"
-"log <name> <rate> - setup log topic rate\n"
-"l <str> - show log values starting with str\n"
-"l expose <name> - expose log value to telemetry\n"
 "sys - show system info\n"
 "reset - reset drone's state\n"
 "reboot - reboot the drone\n";
@@ -159,38 +153,27 @@ void doCommand(String str, bool echo = false) {
 	} else if (command == "mot") {
 		print("front-right %g front-left %g rear-right %g rear-left %g\n",
 			motors[MOTOR_FRONT_RIGHT], motors[MOTOR_FRONT_LEFT], motors[MOTOR_REAR_RIGHT], motors[MOTOR_REAR_LEFT]);
-	} else if (command == "log" && arg0 == "") {
+	} else if (command == "log") {
-		printLogInfo();
-	} else if (command == "log" && arg1 != "") {
-		configLogThrottle(arg0.c_str(), arg1.toFloat());
-	} else if (command == "log" && arg0 == "header") {
 		printLogHeader();
-	} else if (command == "log" && arg0 == "reset") {
+		if (arg0 == "dump") printLogData();
-		resetLog();
-	} else if (command == "l" && arg0 == "expose" && arg1 != "") {
-		exposeLogValue(arg1.c_str());
-	} else if (command == "l") {
-		printLogValues(arg0.c_str());
 	} else if (command == "cr") {
 		calibrateRC();
 	} else if (command == "ca") {
 		calibrateAccel();
 	} else if (command == "mfr") {
-		testMotor(MOTOR_FRONT_RIGHT);
+		testMotor(MOTOR_FRONT_RIGHT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "mfl") {
-		testMotor(MOTOR_FRONT_LEFT);
+		testMotor(MOTOR_FRONT_LEFT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "mrr") {
-		testMotor(MOTOR_REAR_RIGHT);
+		testMotor(MOTOR_REAR_RIGHT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "mrl") {
-		testMotor(MOTOR_REAR_LEFT);
+		testMotor(MOTOR_REAR_LEFT, arg0.isEmpty() ? 0.2 : arg0.toFloat());
 	} else if (command == "sys") {
 #ifdef ESP32
 		print("Chip: %s\n", ESP.getChipModel());
 		print("Temperature: %.1f °C\n", temperatureRead());
 		print("Total RAM: %d KB\n", ESP.getHeapSize() / 1024);
 		print("Free heap: %d KB\n", ESP.getFreeHeap() / 1024);
-		print("PSRAM: %d KB\n", ESP.getPsramSize() / 1024);
-		print("Free PSRAM: %d KB\n", ESP.getFreePsram() / 1024);
 		print("Firmware: " __DATE__ " " __TIME__ "\n");
 		// Print tasks table
 		print("Num  Task                MinSt  Prio  Core  CPU%%\n");

flix/config.h

@@ -0,0 +1,27 @@
+// Copyright (c) 2026 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Parameter defaults
+
+#pragma once
+
+void setDefaults() {
+	// Set defaults here
+
+	#if defined(CONFIG_IDF_TARGET_ESP32S3) || defined(CONFIG_IDF_TARGET_ESP32C3)
+		pwmFrequency = 38000;
+	#endif
+
+	#ifdef FLIX2
+		imuModel = 4; // ICM-40609-D
+		imuIntPin = 10;
+		imuCsPin = 14;
+
+		motorPins[MOTOR_REAR_LEFT] = 41;
+		motorPins[MOTOR_REAR_RIGHT] = 7;
+		motorPins[MOTOR_FRONT_RIGHT] = 18;
+		motorPins[MOTOR_FRONT_LEFT] = 38;
+
+		voltagePin = 3;
+	#endif
+}

flix/control.ino

@@ -9,31 +9,6 @@
 #include "filter.h"
 #include "util.h"
 
-#define PITCHRATE_P 0.05
-#define PITCHRATE_I 0.2
-#define PITCHRATE_D 0.001
-#define PITCHRATE_I_LIM 0.3
-#define ROLLRATE_P PITCHRATE_P
-#define ROLLRATE_I PITCHRATE_I
-#define ROLLRATE_D PITCHRATE_D
-#define ROLLRATE_I_LIM PITCHRATE_I_LIM
-#define YAWRATE_P 0.3
-#define YAWRATE_I 0.0
-#define YAWRATE_D 0.0
-#define YAWRATE_I_LIM 0.3
-#define ROLL_P 6
-#define ROLL_I 0
-#define ROLL_D 0
-#define PITCH_P ROLL_P
-#define PITCH_I ROLL_I
-#define PITCH_D ROLL_D
-#define YAW_P 3
-#define PITCHRATE_MAX radians(360)
-#define ROLLRATE_MAX radians(360)
-#define YAWRATE_MAX radians(300)
-#define TILT_MAX radians(30)
-#define RATES_D_LPF_ALPHA 0.2 // cutoff frequency ~ 40 Hz
-
 const int RAW = 0, ACRO = 1, STAB = 2, AUTO = 3; // flight modes
 int mode = STAB;
 bool armed = false;
@@ -44,14 +19,14 @@ Vector ratesExtra; // feedforward rates
 Vector torqueTarget;
 float thrustTarget;
 
-PID rollRatePID(ROLLRATE_P, ROLLRATE_I, ROLLRATE_D, ROLLRATE_I_LIM, RATES_D_LPF_ALPHA);
+PID rollRatePID(0.05, 0.2, 0.001, 0.3, 0.2);
-PID pitchRatePID(PITCHRATE_P, PITCHRATE_I, PITCHRATE_D, PITCHRATE_I_LIM, RATES_D_LPF_ALPHA);
+PID pitchRatePID(0.05, 0.2, 0.001, 0.3, 0.2);
-PID yawRatePID(YAWRATE_P, YAWRATE_I, YAWRATE_D);
+PID yawRatePID(0.3, 0, 0, 0.3);
-PID rollPID(ROLL_P, ROLL_I, ROLL_D);
+PID rollPID(6);
-PID pitchPID(PITCH_P, PITCH_I, PITCH_D);
+PID pitchPID(6);
-PID yawPID(YAW_P, 0, 0);
+PID yawPID(3);
-Vector maxRate(ROLLRATE_MAX, PITCHRATE_MAX, YAWRATE_MAX);
+Vector maxRate(radians(360), radians(360), radians(360));
-float tiltMax = TILT_MAX;
+float tiltMax = radians(30);
 int flightModes[] = {STAB, STAB, STAB}; // map for rc mode switch
 
 extern const int MOTOR_REAR_LEFT, MOTOR_REAR_RIGHT, MOTOR_FRONT_RIGHT, MOTOR_FRONT_LEFT;

flix/estimate.ino

@@ -15,12 +15,6 @@ bool landed;
 float accWeight = 0.003;
 float levelWeight = 0.0002;
 LowPassFilter<Vector> ratesFilter(0.2); // cutoff frequency ~ 40 Hz
-NotchFilter<Vector> ratesNotch(382, 40);
-
-void setupEstimate() {
-	print("Setup estimation\n");
-	ratesNotch.reset();
-}
 
 void estimate() {
 	applyGyro();
@@ -31,7 +25,6 @@ void estimate() {
 void applyGyro() {
 	// filter gyro to get angular rates
 	rates = ratesFilter.update(gyro);
-	rates = ratesNotch.update(rates);
 
 	// apply rates to attitude
 	attitude = Quaternion::rotate(attitude, Quaternion::fromRotationVector(rates * dt));

flix/filter.h

@@ -1,7 +1,7 @@
 // Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
 // Repository: https://github.com/okalachev/flix
 
-// Low pass and notch filters
+// Low pass filter implementation
 
 #pragma once
 
@@ -32,67 +32,3 @@ public:
 private:
 	bool init = false;
 };
-
-template <typename T>
-class NotchFilter {
-public:
-	float frequency;
-	float bandwidth;
-	T output;
-
-	NotchFilter(float frequency, float bandwidth): frequency(frequency), bandwidth(bandwidth) {
-		reset();
-	};
-
-	T update(const T input) {
-		if (frequency <= 0 || bandwidth <= 0) return input;
-
-		if (!init) {
-			init = true;
-			x1 = x2 = input;
-			y1 = y2 = input;
-			return output = input;
-		}
-
-		output = b0 * input + b1 * x1 + b2 * x2 - a1 * y1 - a2 * y2;
-
-		x2 = x1;
-		x1 = input;
-		y2 = y1;
-		y1 = output;
-
-		return output;
-	}
-
-	void reset() {
-		const float dt = 0.001f;
-		float f = frequency;
-		float bw = bandwidth;
-		if (f < 0) f = 0;
-		if (bw < 1e-6f) bw = 1e-6f;
-
-		float q = f / bw;
-		if (q < 1e-3f) q = 1e-3f;
-
-		const float w0 = 2.0f * PI * f * dt;
-		const float c = cos(w0);
-		const float s = sin(w0);
-		const float alpha = s / (2.0f * q);
-
-		const float a0 = 1.0f + alpha;
-		const float invA0 = 1.0f / a0;
-
-		b0 = 1.0f * invA0;
-		b1 = -2.0f * c * invA0;
-		b2 = 1.0f * invA0;
-		a1 = -2.0f * c * invA0;
-		a2 = (1.0f - alpha) * invA0;
-
-		init = false;
-	}
-
-private:
-	float b0, b1, b2, a1, a2;
-	T x1, x2, y1, y2;
-	bool init = false;
-};

flix/flix.ino

@@ -26,8 +26,6 @@ void setup() {
 	setupWiFi();
 	setupIMU();
 	setupRC();
-	setupEstimate();
-	setupLog();
 	setLED(false);
 	print("Initializing complete\n");
 }
@@ -42,6 +40,6 @@ void loop() {
 	handleInput();
 	processMavlink();
 	readVoltage();
-	loopLog();
+	logData();
 	syncParameters();
 }

flix/imu.ino

@@ -4,12 +4,17 @@
 // Work with the IMU sensor
 
 #include <SPI.h>
+#include <Wire.h>
 #include <FlixPeriph.h>
 #include "vector.h"
 #include "filter.h"
 #include "util.h"
 
-MPU9250 imu(SPI);
+IMU *imu;
+int imuModel = -1; // 1 - MPU9250, 2 - ICM20948, 3 - MPU6050, 4 - ICM40609D
+int imuBus = 0; // 0 - SPI, 1 - I2C
+int imuSckPin = SCK, imuMisoPin = MISO, imuMosiPin = MOSI, imuCsPin = SS, imuIntPin = -1;
+int imuSdaPin = SDA, imuSclPin = SCL;
 Vector imuRotation(0, 0, PI / 2); // imu orientation as Euler angles
 
 Vector gyro; // gyroscope output, rad/s
@@ -23,22 +28,35 @@ LowPassFilter<Vector> gyroBiasFilter(0.001);
 
 void setupIMU() {
 	print("Setup IMU\n");
-	imu.begin();
+	free(imu);
+	if (imuModel == 3) imuBus = 1; // MPU6050 is I2C only
+
+	if (imuBus == 0) {
+		// SPI connection
+		SPI.begin(imuSckPin, imuMisoPin, imuMosiPin);
+		imu = IMU::create(imuModel, SPI, imuCsPin, imuIntPin);
+	} else {
+		// I2C connection
+		Wire.setPins(imuSdaPin, imuSclPin);
+		imu = IMU::create(imuModel, Wire, imuIntPin);
+	}
+
+	imu->begin();
 	configureIMU();
 }
 
 void configureIMU() {
-	imu.setAccelRange(imu.ACCEL_RANGE_4G);
+	imu->setAccelRange(IMU::ACCEL_RANGE_4G);
-	imu.setGyroRange(imu.GYRO_RANGE_2000DPS);
+	imu->setGyroRange(IMU::GYRO_RANGE_2000DPS);
-	imu.setDLPF(imu.DLPF_MAX);
+	imu->setDLPF(IMU::DLPF_MAX);
-	imu.setRate(imu.RATE_1KHZ_APPROX);
+	imu->setRate(IMU::RATE_1KHZ_APPROX);
-	imu.setupInterrupt();
+	imu->setupInterrupt();
 }
 
 void readIMU() {
-	imu.waitForData();
+	imu->waitForData();
-	imu.getGyro(gyro.x, gyro.y, gyro.z);
+	imu->getGyro(gyro.x, gyro.y, gyro.z);
-	imu.getAccel(acc.x, acc.y, acc.z);
+	imu->getAccel(acc.x, acc.y, acc.z);
 	calibrateGyroOnce();
 
 	// Apply scale and bias
@@ -60,7 +78,7 @@ void calibrateGyroOnce() {
 
 void calibrateAccel() {
 	print("Calibrating accelerometer\n");
-	imu.setAccelRange(imu.ACCEL_RANGE_2G); // the most sensitive mode
+	imu->setAccelRange(IMU::ACCEL_RANGE_2G); // the most sensitive mode
 
 	print("1/6 Place level [8 sec]\n");
 	pause(8);
@@ -94,9 +112,9 @@ void calibrateAccelOnce() {
 	// Compute the average of the accelerometer readings
 	acc = Vector(0, 0, 0);
 	for (int i = 0; i < samples; i++) {
-		imu.waitForData();
+		imu->waitForData();
 		Vector sample;
-		imu.getAccel(sample.x, sample.y, sample.z);
+		imu->getAccel(sample.x, sample.y, sample.z);
 		acc = acc + sample;
 	}
 	acc = acc / samples;
@@ -121,17 +139,18 @@ void printIMUCalibration() {
 }
 
 void printIMUInfo() {
-	imu.status() ? print("status: ERROR %d\n", imu.status()) : print("status: OK\n");
+	imu->status() ? print("status: ERROR %d\n", imu->status()) : print("status: OK\n");
-	print("model: %s\n", imu.getModel());
+	print("model: %s\n", imu->getModel());
-	print("who am I: 0x%02X\n", imu.whoAmI());
+	print("who am I: 0x%02X\n", imu->whoAmI());
 	print("rate: %.0f\n", loopRate);
-	print("temperature: %.1f °C\n", imu.getTemp());
+	print("interrupt mode: %s\n", imuIntPin != -1 ? "pin" : "timer");
+	print("temperature: %.1f °C\n", imu->getTemp());
 	print("gyro: %f %f %f\n", gyro.x, gyro.y, gyro.z);
 	print("acc: %f %f %f\n", acc.x, acc.y, acc.z);
-	imu.waitForData();
+	imu->waitForData();
 	Vector rawGyro, rawAcc;
-	imu.getGyro(rawGyro.x, rawGyro.y, rawGyro.z);
+	imu->getGyro(rawGyro.x, rawGyro.y, rawGyro.z);
-	imu.getAccel(rawAcc.x, rawAcc.y, rawAcc.z);
+	imu->getAccel(rawAcc.x, rawAcc.y, rawAcc.z);
 	print("raw gyro: %f %f %f\n", rawGyro.x, rawGyro.y, rawGyro.z);
 	print("raw acc: %f %f %f\n", rawAcc.x, rawAcc.y, rawAcc.z);
 }

flix/log.ino

@@ -1,272 +1,77 @@
 // Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
 // Repository: https://github.com/okalachev/flix
 
-// Logging subsystem
+// In-RAM logging
 
 #include "vector.h"
 #include "util.h"
 
-int logMemory = 0; // 0 - RAM, 1 - PSRAM, -1 - disabled
+#define LOG_RATE 100
-float logUsage = 0.5; // fraction of free memory to use for log
+#define LOG_DURATION 10
+#define LOG_SIZE LOG_DURATION * LOG_RATE
 
-struct LogValue {
+Vector attitudeEuler;
+Vector attitudeTargetEuler;
+
+struct LogEntry {
 	const char *name;
-	Value value;
+	float *value;
-	float lastValue = NAN;
-	bool logged = true; // if false, use only for triggering log update
-	LogValue() : name(nullptr), value() {}; // empty value constructor
-	template <typename T>
-	LogValue(const char *name, T value, bool logged = true) : name(name), value(value), logged(logged) {};
 };
 
-struct LogTopic {
+LogEntry logEntries[] = {
-	LogValue values[10];
+	{"t", &t},
-	int length = 0; // number of logged values
-	float throttle; // max update rate, Hz
-	float lastUpdate = -INFINITY;
-
-	LogTopic(float throttle, LogValue v0, LogValue v1 = {}, LogValue v2 = {}, LogValue v3 = {}, LogValue v4 = {}, LogValue v5 = {}, LogValue v6 = {}, LogValue v7 = {}, LogValue v8 = {}, LogValue v9 = {}) :
-		throttle(throttle), values{v0, v1, v2, v3, v4, v5, v6, v7, v8, v9} {
-			// Count logged values
-			for (auto& v : values) {
-				if (v.name == nullptr) break;
-				if (v.logged) length++;
-			}
-		};
-
-	LogTopic(LogValue v0, LogValue v1 = {}, LogValue v2 = {}, LogValue v3 = {}, LogValue v4 = {}, LogValue v5 = {}, LogValue v6 = {}, LogValue v7 = {}, LogValue v8 = {}, LogValue v9 = {}) :
-		LogTopic(INFINITY, v0, v1, v2, v3, v4, v5, v6, v7, v8, v9) {};
-};
-
-LogTopic logTopics[] = {
-	// time
-	LogTopic({"t", &t}), // must be the first topic
-	LogTopic(1, {"loopRate", &loopRate}),
-
-	// imu
-	LogTopic(
-		{"gyro.x", &gyro.x},
-		{"gyro.y", &gyro.y},
-		{"gyro.z", &gyro.z}),
-
-	LogTopic(50,
-		{"acc.x", &acc.x},
-		{"acc.y", &acc.y},
-		{"acc.z", &acc.z}),
-
-	LogTopic(10,
-		{"gyroBias.x", &gyroBias.x},
-		{"gyroBias.y", &gyroBias.y},
-		{"gyroBias.z", &gyroBias.z}),
-
-	// estimation
-	LogTopic(50,
 	{"rates.x", &rates.x},
 	{"rates.y", &rates.y},
 	{"rates.z", &rates.z},
-		{"attitude.roll", []() { return attitude.getRoll(); }},
-		{"attitude.pitch", []() { return attitude.getPitch(); }},
-		{"attitude.yaw", []() { return attitude.getYaw(); }}),
-
-	// rc
-	LogTopic(10,
-		{"controlTime", &controlTime, false}, // trigger value
-		{"controlRoll", &controlRoll},
-		{"controlPitch", &controlPitch},
-		{"controlYaw", &controlYaw},
-		{"controlThrottle", &controlThrottle}),
-
-	// control
-	LogTopic({"armed", &armed}),
-	LogTopic({"mode", &mode}),
-
-	LogTopic(10,
 	{"ratesTarget.x", &ratesTarget.x},
 	{"ratesTarget.y", &ratesTarget.y},
 	{"ratesTarget.z", &ratesTarget.z},
-		{"attitudeTarget.roll", []() { return attitudeTarget.getRoll(); }},
+	{"attitude.x", &attitudeEuler.x},
-		{"attitudeTarget.pitch", []() { return attitudeTarget.getPitch(); }},
+	{"attitude.y", &attitudeEuler.y},
-		{"attitudeTarget.yaw", []() { return attitudeTarget.getYaw(); }},
+	{"attitude.z", &attitudeEuler.z},
-		{"thrustTarget", &thrustTarget}),
+	{"attitudeTarget.x", &attitudeTargetEuler.x},
-
+	{"attitudeTarget.y", &attitudeTargetEuler.y},
-	// motors
+	{"attitudeTarget.z", &attitudeTargetEuler.z},
-	LogTopic(
+	{"thrustTarget", &thrustTarget}
-		{"motors[0]", &motors[0]},
-		{"motors[1]", &motors[1]},
-		{"motors[2]", &motors[2]},
-		{"motors[3]", &motors[3]}),
-
-	// misc
-	LogTopic(5,
-		{"voltage", &voltage},
-		{"temp", &temperatureRead},
-		{"imuTemp", []() { return imu.getTemp(); }}),
 };
 
-void *logBuffer; // buffer for log data
+const int logColumns = sizeof(logEntries) / sizeof(logEntries[0]);
-size_t logCapacity;
+float logBuffer[LOG_SIZE][logColumns];
-size_t logCursor = 0;
-size_t logLength = 0;
-LogValue *logExposed = nullptr; // log values exposed to telemetry
 
-void setupLog() {
+void prepareLogData() {
-	print("Setup log\n");
+	attitudeEuler = attitude.toEuler();
-
+	attitudeTargetEuler = attitudeTarget.toEuler();
-	free(logBuffer); // when reconfiguring
-	logBuffer = nullptr;
-	logCursor = 0;
-	logLength = 0;
-
-	if (logMemory == 0) {
-		logCapacity = ESP.getFreeHeap() * logUsage;
-		logBuffer = (uint8_t *)calloc(logCapacity, 1);
-	} else if (logMemory == 1) {
-		logCapacity = ESP.getFreePsram() * logUsage;
-		logBuffer = (uint8_t *)heap_caps_calloc(logCapacity, 1, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
-	}
 }
 
-void loopLog() {
+void logData() {
-	if (logBuffer == nullptr || !armed) return;
+	if (!armed) return;
+	static int logPointer = 0;
+	static Rate period(LOG_RATE);
+	if (!period) return;
 
-	if (!logLength) resetLog(); // reset state on first log write
+	prepareLogData();
 
-	static Rate sync(2);
+	for (int i = 0; i < logColumns; i++) {
-	if (sync) {
+		logBuffer[logPointer][i] = *logEntries[i].value;
-		const uint8_t marker[] = {0x1A, 0x91, 0x4F, 0xF6, 0x7F};
-		writeLog(&marker, sizeof(marker)); // write sync marker
 	}
 
-	for (uint8_t i = 0; i < sizeof(logTopics) / sizeof(logTopics[0]); i++) {
+	logPointer++;
-		LogTopic& topic = logTopics[i];
+	if (logPointer >= LOG_SIZE) {
-		if (t - topic.lastUpdate < 1 / topic.throttle) continue; // throttle topic
+		logPointer = 0;
-		if (!isTopicUpdated(i)) continue; // skip if topic was't updated
-
-		topic.lastUpdate = t;
-		writeLog(&i, sizeof(i)); // write topic index
-
-		for (auto& value : topic.values) {
-			if (value.name == nullptr) break;
-			if (!value.logged) continue;
-			value.lastValue = value.value.get();
-			writeLog(&value.lastValue, sizeof(float)); // write value
 	}
 }
-}
-
-void resetLog() {
-	for (auto& topic : logTopics) {
-		topic.lastUpdate = -INFINITY;
-		for (auto& value : topic.values) {
-			value.lastValue = NAN;
-		}
-	}
-	logCursor = 0;
-	logLength = 0;
-}
-
-void writeLog(const void *data, size_t size) {
-	size_t first = min(size, logCapacity - logCursor);
-	size_t second = size - first;
-	memcpy(logBuffer + logCursor, data, first);
-	logCursor = (logCursor + first) % logCapacity;
-	if (second > 0) {
-		memcpy(logBuffer + logCursor, data + first, second);
-		logCursor = (logCursor + second) % logCapacity;
-	}
-	logLength = min(logLength + size, logCapacity);
-}
-
-void readLog(void *data, size_t position, size_t size) {
-	if (logLength == logCapacity) {
-		position = (logCursor + position) % logCapacity;
-	}
-	size_t first = min(size, logCapacity - position);
-	size_t second = size - first;
-	memcpy(data, logBuffer + position, first);
-	if (second > 0) {
-		memcpy(data + first, logBuffer, second);
-	}
-}
-
-bool isTopicUpdated(const uint8_t topic) {
-	LogTopic& logTopic = logTopics[topic];
-	bool updated = false;
-
-	for (auto& value : logTopic.values) {
-		if (value.name == nullptr) break;
-		float v = value.value.get();
-		if (!floatEquals(value.lastValue, v)) {
-			value.lastValue = v;
-			updated = true;
-		}
-	}
-	return updated;
-}
-
-void printLogInfo() {
-	if (logMemory == -1) return print("Log: disabled\n");
-
-	print("Memory: %s\n", logMemory == 0 ? "RAM" : "PSRAM");
-	print("Usage: %.f%%\n", logUsage * 100);
-	print("Capacity: %u bytes\n", (unsigned)logCapacity);
-	print("Used: %u bytes\n", (unsigned)logLength);
-	print("Estimated duration: %d seconds\n", estimateLogDuration());
-}
-
-int estimateLogDuration() {
-	float bandwidth = 0;
-	for (LogTopic& topic : logTopics) {
-		float rate = isinf(topic.throttle) ? loopRate : topic.throttle;
-		bandwidth += rate * topic.length * sizeof(float);
-	}
-	return logCapacity / bandwidth;
-}
 
 void printLogHeader() {
-	int i = 0;
+	for (int i = 0; i < logColumns; i++) {
-	for (auto& topic : logTopics) {
+		print("%s%s", logEntries[i].name, i < logColumns - 1 ? "," : "\n");
-		print("Topic #%d (%g Hz):\n", i++, topic.throttle);
-		for (auto& value : topic.values) {
-			if (value.name == nullptr) break;
-			print("  %s%s\n", value.name, value.logged ?"" : " (not logged)");
-		}
 	}
 }
 
-void printLogValues(const char *filter) {
+void printLogData() {
-	for (LogTopic& topic : logTopics) {
+	for (int i = 0; i < LOG_SIZE; i++) {
-		for (LogValue& value : topic.values) {
+		if (logBuffer[i][0] == 0) continue; // skip empty records
-			if (value.name == nullptr) break;
+		for (int j = 0; j < logColumns; j++) {
-			if (strncasecmp(value.name, filter, strlen(filter))) continue;
+			print("%g%s", logBuffer[i][j], j < logColumns - 1 ? "," : "\n");
-			print("%s = %g\n", value.name, value.value.get());
 		}
 	}
 }
-
-void configLogThrottle(const char *name, float throttle) {
-	for (LogTopic& topic : logTopics) {
-		for (LogValue& value : topic.values) {
-			if (value.name == nullptr) break;
-			if (strcasecmp(value.name, name) != 0) continue;
-			topic.throttle = throttle;
-			print("Log throttle for %s set to %.1f Hz\n", name, throttle);
-			return;
-		}
-	}
-	print("Log value not found: %s\n", name);
-}
-
-void exposeLogValue(const char *name) {
-	for (int i = 0; i < sizeof(logTopics) / sizeof(logTopics[0]); i++) {
-		LogTopic& topic = logTopics[i];
-		for (LogValue& value : topic.values) {
-			if (value.name == nullptr) break;
-			if (strcasecmp(value.name, name) != 0) continue;
-			logExposed = &value;
-			print("Log value %s exposed\n", name);
-			return;
-		}
-	}
-	print("Log value not found: %s\n", name);
-}

flix/mavlink.ino

@@ -16,9 +16,8 @@ Rate telemetryAttitude(20);
 Rate telemetryRC(10);
 Rate telemetryMotors(10);
 Rate telemetryIMU(15);
-Rate telemetryTopic(10);
 
-bool mavlinkConnected = false;
+float mavlinkTime = NAN; // time of last received message
 String mavlinkPrintBuffer;
 
 void processMavlink() {
@@ -41,7 +40,7 @@ void sendMavlink() {
 		sendMessage(&msg);
 	}
 
-	if (!mavlinkConnected) return; // send only heartbeat until connected
+	if (!valid(mavlinkTime)) return; // send only heartbeat until connected
 
 	if (telemetrySlow) {
 		mavlink_msg_extended_sys_state_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg,
@@ -85,12 +84,6 @@ void sendMavlink() {
 			0, 0, 0, 0);
 		sendMessage(&msg);
 	}
-
-	if (telemetryTopic && logExposed != nullptr) {
-		mavlink_msg_named_value_float_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg,
-			time, logExposed->name, logExposed->value.get());
-		sendMessage(&msg);
-	}
 }
 
 void sendMessage(const void *msg) {
@@ -99,26 +92,6 @@ void sendMessage(const void *msg) {
 	sendWiFi(buf, len);
 }
 
-static uint8_t mavlinkBatch[ESP_NOW_MAX_DATA_LEN_V2];
-static int mavlinkBatchSize = 0;
-
-void batchMessage(const void *msg) {
-	uint8_t buf[MAVLINK_MAX_PACKET_LEN];
-	int len = mavlink_msg_to_send_buffer(buf, (mavlink_message_t *)msg);
-
-	if (mavlinkBatchSize + len > sizeof(mavlinkBatch)) {
-		sendWiFi(mavlinkBatch, mavlinkBatchSize);
-		mavlinkBatchSize = 0;
-	}
-	memcpy(mavlinkBatch + mavlinkBatchSize, buf, len);
-	mavlinkBatchSize += len;
-}
-
-void flushBatchMessages() {
-	sendWiFi(mavlinkBatch, mavlinkBatchSize);
-	mavlinkBatchSize = 0;
-}
-
 void receiveMavlink() {
 	uint8_t buf[MAVLINK_MAX_PACKET_LEN];
 	int len = receiveWiFi(buf, MAVLINK_MAX_PACKET_LEN);
@@ -128,7 +101,7 @@ void receiveMavlink() {
 	mavlink_status_t status;
 	for (int i = 0; i < len; i++) {
 		if (mavlink_parse_char(MAVLINK_COMM_0, buf[i], &msg, &status)) {
-			mavlinkConnected = true;
+			mavlinkTime = t;
 			handleMavlink(&msg);
 		}
 	}
@@ -252,29 +225,18 @@ void handleMavlink(const void *_msg) {
 		armed = motors[0] > 0 || motors[1] > 0 || motors[2] > 0 || motors[3] > 0;
 	}
 
-	if (msg.msgid == MAVLINK_MSG_ID_LOG_REQUEST_LIST) {
-		const uint32_t qgcEpoch = 1262304000; // qgc accepts only timestamps after 2010-01-01
-		mavlink_message_t response;
-		mavlink_msg_log_entry_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &response,
-			0, 1, 0, qgcEpoch + t * 60, logLength); // put fake unique date to make qgc happy with saving logs
-		sendMessage(&response);
-	}
-
 	if (msg.msgid == MAVLINK_MSG_ID_LOG_REQUEST_DATA) {
 		mavlink_log_request_data_t m;
 		mavlink_msg_log_request_data_decode(&msg, &m);
 		if (m.target_system && m.target_system != mavlinkSysId) return;
 
-		for (int i = 0; i < m.count; i += MAVLINK_MSG_LOG_DATA_FIELD_DATA_LEN) {
+		// Send all log records
-			int chunkSize = min(MAVLINK_MSG_LOG_DATA_FIELD_DATA_LEN, (int)(m.count - i));
+		for (int i = 0; i < sizeof(logBuffer) / sizeof(logBuffer[0]); i++) {
-			mavlink_message_t response;
+			mavlink_message_t msg;
-			uint8_t data[MAVLINK_MSG_LOG_DATA_FIELD_DATA_LEN];
+			mavlink_msg_log_data_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &msg, 0, i,
-			readLog(data, m.ofs + i, chunkSize);
+				sizeof(logBuffer[0]), (uint8_t *)logBuffer[i]);
-			mavlink_msg_log_data_pack(mavlinkSysId, MAV_COMP_ID_AUTOPILOT1, &response,
+			sendMessage(&msg);
-				m.id, m.ofs + i, chunkSize, data);
-			batchMessage(&response);
 		}
-		flushBatchMessages();
 	}
 
 	// Handle commands

flix/motors.ino

@@ -51,9 +51,9 @@ bool motorsActive() {
 	return motors[0] != 0 || motors[1] != 0 || motors[2] != 0 || motors[3] != 0;
 }
 
-void testMotor(int n) {
+void testMotor(int n, float thrust) {
 	print("Testing motor %d\n", n);
-	motors[n] = 0.2;
+	motors[n] = thrust;
 	delay(50); // ESP32 may need to wait until the end of the current cycle to change duty https://github.com/espressif/arduino-esp32/issues/5306
 	sendMotors();
 	pause(3);

flix/parameters.ino

@@ -9,11 +9,13 @@
 extern int channelZero[16], channelMax[16];
 extern int rollChannel, pitchChannel, throttleChannel, yawChannel, armedChannel, modeChannel;
 extern int rcRxPin, voltagePin;
-extern int wifiMode, wifiLongRange, udpLocalPort, udpRemotePort, espnowChannel;
+extern int wifiMode, wifiLongRange, wifiBroadcast, udpLocalPort, udpRemotePort, espnowChannel;
-extern float rcLossTimeout, descendTime;
+extern float rcLossTimeout, descendTime, disarmTilt;
 extern float voltageScale;
 extern LowPassFilter<float> voltageFilter;
 
+#include "config.h"
+
 Preferences storage;
 
 struct Parameter {
@@ -44,6 +46,7 @@ Parameter parameters[] = {
 	{"CTL_Y_RATE_P", &yawRatePID.p},
 	{"CTL_Y_RATE_I", &yawRatePID.i},
 	{"CTL_Y_RATE_D", &yawRatePID.d},
+	{"CTL_Y_RATE_WU", &yawRatePID.windup},
 	{"CTL_Y_RATE_D_A", &yawRatePID.lpf.alpha},
 	{"CTL_R_P", &rollPID.p},
 	{"CTL_R_I", &rollPID.i},
@@ -60,6 +63,15 @@ Parameter parameters[] = {
 	{"CTL_FLT_MODE_1", &flightModes[1]},
 	{"CTL_FLT_MODE_2", &flightModes[2]},
 	// imu
+	{"IMU_MODEL", &imuModel},
+	{"IMU_BUS", &imuBus},
+	{"IMU_PIN_SCK", &imuSckPin},
+	{"IMU_PIN_MISO", &imuMisoPin},
+	{"IMU_PIN_MOSI", &imuMosiPin},
+	{"IMU_PIN_CS", &imuCsPin},
+	{"IMU_PIN_SDA", &imuSdaPin},
+	{"IMU_PIN_SCL", &imuSclPin},
+	{"IMU_PIN_INT", &imuIntPin},
 	{"IMU_ROT_ROLL", &imuRotation.x},
 	{"IMU_ROT_PITCH", &imuRotation.y},
 	{"IMU_ROT_YAW", &imuRotation.z},
@@ -74,8 +86,6 @@ Parameter parameters[] = {
 	{"EST_ACC_WEIGHT", &accWeight},
 	{"EST_LVL_WEIGHT", &levelWeight},
 	{"EST_RATES_LPF_A", &ratesFilter.alpha},
-	{"EST_RATES_NF_F", &ratesNotch.frequency, setupEstimate},
-	{"EST_RATES_NF_BW", &ratesNotch.bandwidth, setupEstimate},
 	// motors
 	{"MOT_PIN_FL", &motorPins[MOTOR_FRONT_LEFT], setupMotors},
 	{"MOT_PIN_FR", &motorPins[MOTOR_FRONT_RIGHT], setupMotors},
@@ -114,6 +124,7 @@ Parameter parameters[] = {
 	{"WIFI_PORT_LOC", &udpLocalPort},
 	{"WIFI_PORT_REM", &udpRemotePort},
 	{"WIFI_LONG_RANGE", &wifiLongRange},
+	{"WIFI_BROADCAST", &wifiBroadcast},
 	// espnow
 	{"ESPNOW_CHANNEL", &espnowChannel},
 	// mavlink
@@ -123,22 +134,6 @@ Parameter parameters[] = {
 	{"MAV_RATE_RC", &telemetryRC.rate},
 	{"MAV_RATE_MOT", &telemetryMotors.rate},
 	{"MAV_RATE_IMU", &telemetryIMU.rate},
-	{"MAV_RATE_TOPIC", &telemetryTopic.rate},
-	// log
-	{"LOG_MEMORY", &logMemory, setupLog},
-	{"LOG_USAGE", &logUsage, setupLog},
-	{"LOG_RATE_000", &logTopics[0].throttle},
-	{"LOG_RATE_001", &logTopics[1].throttle},
-	{"LOG_RATE_002", &logTopics[2].throttle},
-	{"LOG_RATE_003", &logTopics[3].throttle},
-	{"LOG_RATE_004", &logTopics[4].throttle},
-	{"LOG_RATE_005", &logTopics[5].throttle},
-	{"LOG_RATE_006", &logTopics[6].throttle},
-	{"LOG_RATE_007", &logTopics[7].throttle},
-	{"LOG_RATE_008", &logTopics[8].throttle},
-	{"LOG_RATE_009", &logTopics[9].throttle},
-	{"LOG_RATE_010", &logTopics[10].throttle},
-	{"LOG_RATE_011", &logTopics[11].throttle},
 	// power
 	{"PWR_VOLT_PIN", &voltagePin, setupPower},
 	{"PWR_VOLT_SCALE", &voltageScale},
@@ -146,10 +141,12 @@ Parameter parameters[] = {
 	// safety
 	{"SF_RC_LOSS_TIME", &rcLossTimeout},
 	{"SF_DESCEND_TIME", &descendTime},
+	{"SF_DISARM_TILT", &disarmTilt},
 };
 
 void setupParameters() {
 	print("Setup parameters\n");
+	setDefaults();
 	storage.begin("flix");
 	// Read parameters from storage
 	for (auto &parameter : parameters) {

flix/pid.h

@@ -18,7 +18,7 @@ public:
 
 	LowPassFilter<float> lpf; // low pass filter for derivative term
 
-	PID(float p, float i, float d, float windup = 0, float dAlpha = 1, float dtMax = 0.1) :
+	PID(float p, float i = 0, float d = 0, float windup = 0, float dAlpha = 1, float dtMax = 0.1) :
 		p(p), i(i), d(d), windup(windup), lpf(dAlpha), dtMax(dtMax) {}
 
 	float update(float error) {

flix/power.ino

@@ -9,7 +9,7 @@
 #include "util.h"
 
 float voltage = NAN;
-LowPassFilter<float> voltageFilter(0.2);
+LowPassFilter<float> voltageFilter(1);
 int voltagePin = -1;
 float voltageScale = 2;
 

flix/safety.ino

@@ -8,10 +8,12 @@ extern float controlRoll, controlPitch, controlThrottle, controlYaw;
 
 float rcLossTimeout = 1;
 float descendTime = 10;
+float disarmTilt = radians(120);
 
 void failsafe() {
 	rcLossFailsafe();
 	autoFailsafe();
+	tiltFailsafe();
 }
 
 // RC loss failsafe
@@ -36,7 +38,7 @@ void descend() {
 // Allow pilot to interrupt automatic flight
 void autoFailsafe() {
 	static float roll, pitch, yaw, throttle;
-	if (roll != controlRoll || pitch != controlPitch || yaw != controlYaw || abs(throttle - controlThrottle) > 0.05) {
+	if (abs(roll - controlRoll) > 0.05 || abs(pitch - controlPitch) > 0.05 || abs(yaw - controlYaw) > 0.05 || abs(throttle - controlThrottle) > 0.05) {
 		// controls changed and mode switch is not configured
 		if (mode == AUTO && invalid(controlMode)) mode = STAB; // regain control by the pilot
 	}
@@ -45,3 +47,15 @@ void autoFailsafe() {
 	yaw = controlYaw;
 	throttle = controlThrottle;
 }
+
+// Disarm if tilted too much
+void tiltFailsafe() {
+	if (!armed) return;
+	if (mode != STAB) return;
+
+	Vector up = Quaternion::rotateVector(Vector(0, 0, 1), attitude);
+	float tilt = acos(up.z);
+	if (disarmTilt && tilt > disarmTilt) {
+		armed = false;
+	}
+}

flix/util.h

@@ -64,54 +64,11 @@ public:
 	}
 };
 
-// Simple variant type for logging and parameters
-struct Value {
-	enum { EMPTY, FLOAT, INT, BOOL, FLOAT_FN, INT_FN, BOOL_FN } type;
-	union {
-		void *pointer;
-		float *_float;
-		int *_int;
-		bool *_bool;
-		float (*floatFn)();
-		int (*intFn)();
-		bool (*boolFn)();
-	};
-
-	Value() : type(EMPTY), pointer(nullptr) {};
-	Value(float *pt) : type(FLOAT), _float(pt) {};
-	Value(int *pt) : type(INT), _int(pt) {};
-	Value(bool *pt) : type(BOOL), _bool(pt) {};
-	Value(float (*fn)()) : type(FLOAT_FN), floatFn(fn) {};
-	Value(int (*fn)()) : type(INT_FN), intFn(fn) {};
-	Value(bool (*fn)()) : type(BOOL_FN), boolFn(fn) {};
-
-	float get() const {
-		switch (type) {
-			case FLOAT: return *_float;
-			case INT: return *_int;
-			case BOOL: return *_bool ? 1 : 0;
-			case FLOAT_FN: return floatFn();
-			case INT_FN: return intFn();
-			case BOOL_FN: return boolFn() ? 1 : 0;
-			default: return NAN;
-		}
-	};
-
-	void set(float value) const {
-		switch (type) {
-			case FLOAT: *_float = value; break;
-			case INT: *_int = value; break;
-			case BOOL: *_bool = (value != 0); break;
-			default: break;
-		}
-	};
-};
-
 // Rate limiter
 class Rate {
 public:
 	float rate;
-	float last = 0;
+	float last = -INFINITY;
 	Rate(float rate) : rate(rate) {}
 
 	operator bool() {

flix/wifi.ino

@@ -17,6 +17,7 @@ const int W_DISABLED = 0, W_AP = 1, W_STA = 2, W_ESPNOW = 3;
 int wifiMode = W_AP;
 
 int wifiLongRange = 0;
+int wifiBroadcast = 0; // 0 - broadcast until connected, 1 - always broadcast
 int udpLocalPort = 14550;
 int udpRemotePort = 14550;
 IPAddress udpRemoteIP = "255.255.255.255";
@@ -58,13 +59,14 @@ void sendWiFi(const uint8_t *buf, int len) {
 		espnow.write(buf, len);
 
 		static Rate discovery(2);
-		if (discovery) espnowBroadcast.write((const uint8_t *)"flix", 4); // broadcast message to help finding this device
+		if (espnow.isEncrypted() && discovery) espnowBroadcast.write((const uint8_t *)"flix", 4); // broadcast message to help finding this device
 		return;
 	}
 
 	if (WiFi.softAPgetStationNum() == 0 && !WiFi.isConnected()) return;
 
-	udp.beginPacket(udpRemoteIP, udpRemotePort);
+	bool broadcast = wifiBroadcast || !(t - mavlinkTime < 5); // broadcast if lost connection
+	udp.beginPacket(broadcast ? IPAddress(255, 255, 255, 255) : udpRemoteIP, udpRemotePort);
 	udp.write(buf, len);
 	udp.endPacket();
 }
@@ -113,7 +115,7 @@ void printWiFiInfo() {
 	} else {
 		print("Mode: Disabled\n");
 	}
-	print("MAVLink connected: %d\n", mavlinkConnected);
+	print("MAVLink connected: %d\n", valid(mavlinkTime));
 }
 
 void configWiFi(int mode, const char *first, const char *second) {

gazebo/Arduino.h

@@ -156,7 +156,6 @@ HardwareSerial Serial, Serial1, Serial2;
 class EspClass {
 public:
 	void restart() { Serial.println("Ignore reboot in simulation"); }
-	uint32_t getFreeHeap() { return 300 * 1024; } // assume 300 KB free heap
 } ESP;
 
 unsigned long __delayTime = 0;

gazebo/flix.h

@@ -21,6 +21,9 @@ extern float motors[4];
 Vector gyro, acc, imuRotation;
 Vector accBias, gyroBias, accScale(1, 1, 1);
 LowPassFilter<Vector> gyroBiasFilter(0);
+int imuModel = 1, imuBus = 0;
+int imuSckPin = 0, imuMisoPin = 0, imuMosiPin = 0, imuCsPin = -1, imuIntPin = -1;
+int imuSdaPin = 0, imuSclPin = 0;
 
 // declarations
 void step();
@@ -38,7 +41,7 @@ const char* getModeName();
 void sendMotors();
 int getDutyCycle(float value);
 bool motorsActive();
-void testMotor(int n);
+void testMotor(int, float);
 void print(const char* format, ...);
 void pause(float duration);
 void doCommand(String str, bool echo);
@@ -48,17 +51,8 @@ void normalizeRC();
 void calibrateRC();
 void calibrateRCChannel(int*, uint16_t[16], uint16_t[16], const char*);
 void printRCCalibration();
-void loopLog();
-void resetLog();
-void writeLog(const void *data, size_t size);
-void readLog(void *data, size_t position, size_t size);
-bool isTopicUpdated(const uint8_t topic);
-void printLogInfo();
-int estimateLogDuration();
 void printLogHeader();
-void printLogValues(const char *filter);
+void printLogData();
-void configLogThrottle(const char *name, float throttle);
-void exposeLogValue(const char *name);
 void processMavlink();
 void sendMavlink();
 void sendMessage(const void *msg);
@@ -72,6 +66,7 @@ void failsafe();
 void rcLossFailsafe();
 void descend();
 void autoFailsafe();
+void tiltFailsafe();
 int parametersCount();
 const char *getParameterName(int index);
 float getParameter(int index);
@@ -82,7 +77,6 @@ void resetParameters();
 
 // mocks
 void setLED(bool on) {};
-void calibrateGyro() { print("Skip gyro calibrating\n"); };
 void calibrateAccel() { print("Skip accel calibrating\n"); };
 void printIMUCalibration() { print("cal: N/A\n"); };
 void printIMUInfo() {};

gazebo/simulator.cpp

@@ -55,7 +55,7 @@ public:
 		initNode();
 		Serial.begin(0);
 		setupParameters();
-		setupLog();
+		rcRxPin = 1; // set rc pin to enable rc reading
 		gzmsg << "Flix plugin loaded" << endl;
 	}
 

tools/csv_to_mcap.py

@@ -9,7 +9,6 @@ Usage:
 import csv
 import json
 import docopt
-import math
 from mcap.writer import Writer
 
 args = docopt.docopt(__doc__)
@@ -40,15 +39,7 @@ channel_id = writer.register_channel(
 )
 
 for row in csv_reader:
-    if row[0] == '': continue
+    data = {key: float(value) for key, value in zip(header, row)}
-    data = {}
-    for key, value in zip(header, row):
-        if value == '' or math.isnan(float(value)):
-            data[key] = None
-        else:
-            data[key] = float(value)
-
-    data = {key: float(value) if value != '' else None for key, value in zip(header, row)}
     timestamp = round(float(row[0]) * 1e9)
     writer.add_message(channel_id=channel_id, log_time=timestamp, data=json.dumps(data).encode(), publish_time=timestamp,)
 

tools/log_to_csv.py

@@ -1,76 +0,0 @@
-#!/usr/bin/env python3
-
-"""Convert flight from Flix format to CSV
-
-Usage:
-    log_to_csv.py <input_file>
-"""
-
-import os
-from pyflix import Flix
-import docopt
-import struct
-import csv
-
-DIR = os.path.dirname(os.path.realpath(__file__))
-HEADER_FILE = os.path.join(DIR, 'log/log_header.txt')
-
-# Read log header
-try:
-    # read from file
-    header = open(HEADER_FILE, 'r').read()
-except FileNotFoundError:
-    flix = Flix()
-    header = flix.cli('log header')  # receive the log schema
-    open(HEADER_FILE, 'w').write(header)  # save to file
-
-# Parse log header
-topics = []
-for line in header.splitlines():
-    if not line.startswith('  '):
-        topics.append([])
-    elif 'not logged' not in line:
-        topics[-1].append(line.strip())
-
-# Read log file
-args = docopt.docopt(__doc__)
-input_file = args['<input_file>']
-outfile_file = input_file + '.csv'
-data = open(input_file, 'rb').read()
-
-# Search for sync marker
-SYNC_MARKER = bytes.fromhex('1A 91 4F F6 7F')
-sync_offset = data.find(SYNC_MARKER)
-if sync_offset == -1:
-    raise ValueError('Sync marker not found in log file')
-data = data[sync_offset + len(SYNC_MARKER):]
-data = data.replace(SYNC_MARKER, b'')  # remove all other sync markers
-
-header_row = [f'{value}' for topic in topics for value in topic]
-rows = []
-
-offset = 0
-while offset < len(data):
-    try:
-        topic = struct.unpack_from('B', data, offset)[0]
-        offset += 1
-
-        if topic >= len(topics):
-            raise ValueError(f'Invalid topic {topic} at offset {offset}')
-
-        if topic == 0 or not rows:
-            rows.append({})
-
-        for name in topics[topic]:
-            value = struct.unpack_from('<f', data, offset)[0]
-            offset += 4
-            rows[-1][name] = value
-    except struct.error as e:
-        break
-
-# Write CSV file
-with open(outfile_file, 'w', newline='') as f:
-    writer = csv.DictWriter(f, fieldnames=header_row, extrasaction='ignore')
-    writer.writeheader()
-    rows = filter(lambda row: float(row.get('t', 0)), rows)
-    writer.writerows(rows)