Merge branch 'esp32' into 'master'

Esp32 See merge request vato007/picar!5
2020-09-13 12:07:39 +00:00
parent 98c7dd0114 0026aade39
commit 2944e1b5eb
23 changed files with 406 additions and 71 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -32,4 +32,6 @@ SwiftyCar/Sources/SwiftyCar/car
 xcuserdata/
 .settings
 .project
-.classpath
+.classpath
+
+.vscode/settings.json
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -15,6 +15,12 @@ build_pycar_docker:
    - echo ${DOCKER_PASSWORD} | docker login vato.ddns.net:8083 --username ${DOCKER_USERNAME} --password-stdin
    - docker build -f pycar/Dockerfile --build-arg PYPI_USERNAME=${PYPI_USERNAME} --build-arg PYPI_PASSWORD=${PYPI_PASSWORD} -t vato.ddns.net:8082/pycar:latest pycar

+build_esp32:
+  image: vato.ddns.net:8083/shaguarger/platformio
+  stage: build
+  script:
+    - platformio ci --project-conf esp32/platformio.ini esp32
+
 deploy_pycar:
  image: vato.ddns.net:8083/python-infra:buster
  stage: deploy
--- a/.idea/codeStyles/Project.xml
+++ b/.idea/codeStyles/Project.xml
@@ -1,5 +1,23 @@
 <component name="ProjectCodeStyleConfiguration">
  <code_scheme name="Project" version="173">
+    <JetCodeStyleSettings>
+      <option name="PACKAGES_TO_USE_STAR_IMPORTS">
+        <value>
+          <package name="java.util" alias="false" withSubpackages="false" />
+          <package name="kotlinx.android.synthetic" alias="false" withSubpackages="true" />
+          <package name="io.ktor" alias="false" withSubpackages="true" />
+        </value>
+      </option>
+      <option name="PACKAGES_IMPORT_LAYOUT">
+        <value>
+          <package name="" alias="false" withSubpackages="true" />
+          <package name="java" alias="false" withSubpackages="true" />
+          <package name="javax" alias="false" withSubpackages="true" />
+          <package name="kotlin" alias="false" withSubpackages="true" />
+          <package name="" alias="true" withSubpackages="true" />
+        </value>
+      </option>
+    </JetCodeStyleSettings>
    <codeStyleSettings language="XML">
      <indentOptions>
        <option name="CONTINUATION_INDENT_SIZE" value="4" />
--- a/.idea/gradle.xml
+++ b/.idea/gradle.xml
@@ -11,9 +11,10 @@
          <set>
            <option value="$PROJECT_DIR$" />
            <option value="$PROJECT_DIR$/CarControlleriOS" />
+            <option value="$PROJECT_DIR$/SwiftyCar" />
            <option value="$PROJECT_DIR$/app" />
-            <option value="$PROJECT_DIR$/car" />
            <option value="$PROJECT_DIR$/protobuf" />
+            <option value="$PROJECT_DIR$/pycar" />
          </set>
        </option>
        <option name="resolveModulePerSourceSet" value="false" />
--- a/.vscode/launch.json
+++ b/.vscode/launch.json
@@ -10,7 +10,8 @@
            "request": "launch",
            "module": "car",
            "env": {
-                "CAR_VEHICLE": "CAR_MOCK",
+                "CAR_VEHICLE": "VEHICLE_MOCK",
+                // "CAR_VEHICLE": "VEHICLE_SERIAL",
                // "CAR_LIDAR": "/dev/tty.usbserial-0001",
                "CAR_LIDAR": "LIDAR_MOCK"
            }
--- a/SwiftyCar/Package.resolved
+++ b/SwiftyCar/Package.resolved
@@ -6,8 +6,8 @@
        "repositoryURL": "https://github.com/grpc/grpc-swift.git",
        "state": {
          "branch": null,
-          "revision": "b83ee1ee2caa0660eb02444977b9b6e353c2adbf",
-          "version": "1.0.0-alpha.12"
+          "revision": "640b0ef1d0be63bda0ada86786cfda678ab2aae9",
+          "version": "1.0.0-alpha.19"
        }
      },
      {
@@ -15,8 +15,8 @@
        "repositoryURL": "https://github.com/apple/swift-log.git",
        "state": {
          "branch": null,
-          "revision": "74d7b91ceebc85daf387ebb206003f78813f71aa",
-          "version": "1.2.0"
+          "revision": "173f567a2dfec11d74588eea82cecea555bdc0bc",
+          "version": "1.4.0"
        }
      },
      {
@@ -24,8 +24,8 @@
        "repositoryURL": "https://github.com/apple/swift-nio.git",
        "state": {
          "branch": null,
-          "revision": "40bdad80882d307abe2c0bb36cf3bd4d3e03fe04",
-          "version": "2.16.1"
+          "revision": "5fc24345f92ec4c274121776c215ab0aa1ed4d50",
+          "version": "2.22.0"
        }
      },
      {
@@ -33,8 +33,8 @@
        "repositoryURL": "https://github.com/apple/swift-nio-http2.git",
        "state": {
          "branch": null,
-          "revision": "82eb3fa0974b838358ee46bc6c5381e5ae5de6b9",
-          "version": "1.11.0"
+          "revision": "1e68e51752be0b43c5a0ef35818c1dd24d13e77c",
+          "version": "1.14.1"
        }
      },
      {
@@ -42,8 +42,8 @@
        "repositoryURL": "https://github.com/apple/swift-nio-ssl.git",
        "state": {
          "branch": null,
-          "revision": "ae213938e151964aa691f0e902462fbe06baeeb6",
-          "version": "2.7.1"
+          "revision": "ea1dfd64193bf5af4490635a4a44c4fb43b1e1ae",
+          "version": "2.9.1"
        }
      },
      {
@@ -51,8 +51,8 @@
        "repositoryURL": "https://github.com/apple/swift-nio-transport-services.git",
        "state": {
          "branch": null,
-          "revision": "85a67aea7caf5396ed599543dd23cffeb6dbbf96",
-          "version": "1.5.1"
+          "revision": "bb56586c4cab9a79dce6ec4738baddb5802c5de7",
+          "version": "1.9.0"
        }
      },
      {
@@ -60,8 +60,35 @@
        "repositoryURL": "https://github.com/apple/swift-protobuf.git",
        "state": {
          "branch": null,
-          "revision": "7790acf0a81d08429cb20375bf42a8c7d279c5fe",
-          "version": "1.8.0"
+          "revision": "0279688c9fc5a40028e1b5bb0cb56534a45a6020",
+          "version": "1.12.0"
+        }
+      },
+      {
+        "package": "Swift2dCar",
+        "repositoryURL": "https://vato.ddns.net/gitlab/vato007/swift2dcar.git",
+        "state": {
+          "branch": "master",
+          "revision": "970aac902531408614db0a37a7300e9373dafb50",
+          "version": null
+        }
+      },
+      {
+        "package": "SwiftRPLidar",
+        "repositoryURL": "https://vato.ddns.net/gitlab/vato007/swiftrplidar.git",
+        "state": {
+          "branch": "master",
+          "revision": "761eb0bc1a00b4627a7870ffac121a542ff0cd6b",
+          "version": null
+        }
+      },
+      {
+        "package": "SwiftSerial",
+        "repositoryURL": "https://vato.ddns.net/gitlab/vato007/SwiftSerial.git",
+        "state": {
+          "branch": "master",
+          "revision": "27a5d92aa00f6e91581389485994364e16bed2c5",
+          "version": null
        }
      },
      {
@@ -69,8 +96,8 @@
        "repositoryURL": "https://github.com/uraimo/SwiftyGPIO.git",
        "state": {
          "branch": null,
-          "revision": "4127ff9dd5c6aa8acb6be34b7ce2af2f6e0b942d",
-          "version": "1.1.14"
+          "revision": "2038228e020cf12a62012b1ebe36bb9b8e6fdb6a",
+          "version": "1.2.5"
        }
      }
    ]
--- a/SwiftyCar/Package.swift
+++ b/SwiftyCar/Package.swift
@@ -14,7 +14,7 @@ let package = Package(
        .package(url: "https://github.com/grpc/grpc-swift.git", from: "1.0.0-alpha.19"),
        .package(url: "https://github.com/uraimo/SwiftyGPIO.git", from: "1.0.0"),
        .package(url: "https://vato.ddns.net/gitlab/vato007/swiftrplidar.git", .branch("master")),
-        .package(url: "https://vato.ddns.net/gitlab/vato007/SwiftSerial.git", .branch("dtr_support")),
+        .package(url: "https://vato.ddns.net/gitlab/vato007/SwiftSerial.git", .branch("master")),
        .package(url: "https://vato.ddns.net/gitlab/vato007/swift2dcar.git", .branch("master"))
    ],
    targets: [
@@ -22,7 +22,12 @@ let package = Package(
        // Targets can depend on other targets in this package, and on products in packages which this package depends on.
        .target(
            name: "SwiftyCar",
-            dependencies: ["SwiftyGPIO", .product(name: "GRPC", package: "grpc-swift"), "SwiftRPLidar", "SwiftSerial", "Swift2dCar"]),
+            dependencies: [
+                "SwiftyGPIO", 
+                .product(name: "GRPC", package: "grpc-swift"), 
+                "SwiftRPLidar",
+                "SwiftSerial",
+                "Swift2dCar"]),
        .testTarget(
            name: "SwiftyCarTests",
            dependencies: ["SwiftyCar"]),
--- a/SwiftyCar/Sources/SwiftyCar/VehicleFactory.swift
+++ b/SwiftyCar/Sources/SwiftyCar/VehicleFactory.swift
@@ -1,5 +1,5 @@
 //
-//  File.swift
+//  VehicleFactory.swift
 //  
 //
 //  Created by Michael Pivato on 20/5/20.
@@ -8,16 +8,35 @@
 import Foundation
 import SwiftyGPIO
 import Swift2dCar
+import SwiftSerial

-func getVehicle2D() throws -> Vehicle2D {
+func getVehicle2D() throws -> Vehicle2D? {
+    // TODO: Clean up this factory, or see if we can get dependency injection working.
    if let value = ProcessInfo.processInfo.environment["CAR_VEHICLE"] {
        switch value{
-        case "CAR_2D":
+        case "VEHICLE_2D":
            // Get car for rpi.
            let pwms = SwiftyGPIO.hardwarePWMs(for:.RaspberryPi3)!
-            
-            // Read the feature database.
            return try RPiVehicle2D(withThrottlePin: PWMHardwareServo(forPin: (pwms[0]?[.P18])!)!, withSteeringPin:PWMHardwareServo(forPin: (pwms[1]?[.P19])!)!)
+        case "VEHICLE_SERIAL":
+            // TODO: Get from environment variable. tty won't work in macos anyway.
+            // We share the serialport object, as cu will block on macOS (required by SwiftSerial), so can't open 2 of the same port.
+            let serialPort = SerialPort(path: "/dev/ttyUSB0")
+
+            // The port does not open/initialise inside of the ESP32ServoOutputs, as on macOS /dev/cu.* blocks.
+            try initPort.openPort()
+            initPort.setSettings(receiveRate: .baud115200, transmitRate: .baud115200, minimumBytesToRead: 1)x
+            guard let throttlePin = Esp32ServoOutput(forChannel: 1, forPin: 14, onPort: serialPort) else {
+                print("Failed to create throttle pin.")
+                return nil
+            }
+
+            guard let steeringPin = Esp32ServoOutput(forChannel: 2, forPin: 12, onPort: serialPort) else {
+                print("Failed to create steering pin.")
+                return nil
+            }
+
+            return try RPiVehicle2D(withThrottlePin: PWMHardwareServo(forPin: throttlePin)!, withSteeringPin: PWMHardwareServo(forPin: steeringPin)!)
        default:
            return MockVehicle()
        }
--- a/SwiftyCar/Sources/SwiftyCar/main.swift
+++ b/SwiftyCar/Sources/SwiftyCar/main.swift
@@ -24,7 +24,7 @@ func doServer() throws {
        return false
    }
    // Create a provider using the features we read.
-    let provider = try MotorProvider(vehicle: getVehicle2D())
+    let provider = try MotorProvider(vehicle: getVehicle2D()!)
    let trackingProvider = LidarProvider(lidar: lidar)

    // Start the server and print its address once it has started.
--- a/esp32/.gitignore
+++ b/esp32/.gitignore
@@ -0,0 +1,5 @@
+.pio
+.vscode/.browse.c_cpp.db*
+.vscode/c_cpp_properties.json
+.vscode/launch.json
+.vscode/ipch
--- a/esp32/.vscode/extensions.json
+++ b/esp32/.vscode/extensions.json
@@ -0,0 +1,7 @@
+{
+    // See http://go.microsoft.com/fwlink/?LinkId=827846
+    // for the documentation about the extensions.json format
+    "recommendations": [
+        "platformio.platformio-ide"
+    ]
+}
--- a/esp32/README.md
+++ b/esp32/README.md
@@ -0,0 +1,28 @@
+This module includes an arduino sketch designed to run on the ESP32.
+
+The sketch takes simple input from serial (ESP32 microusb port), and converts the input to a duty cycle that can be used on servos.
+
+The protocol specification is as follows, assuming an array of bytes:
+
+
+| Byte Number   | Value Description |
+| :---------- |  ----------: |
+| 0 | 0 if Calibrating a servo. Higher values indicates channel number to set duty cycle on. |
+| 1 | If byte 0 = 0: number of servos to calibrate. Else, the new duty cycle value for the channel specified in byte 0. |
+
+When setting the duty cycle, the current min angle is 0, and the max angle is 255, which allows the entire byte to be used for setting the duty cycle.
+
+The table below describes the byte format for calibrating a servo. This array of bytes can be repeated for the given number of servos in byte 1:
+
+| Byte Number   | Value Description |
+| :----------   |  ----------:      |
+| 0             | Servo channel to set (this will be byte 0 when setting duty cycle, so don't use 0). |
+| 1             | The pin number to setup |
+
+The min/max pulse widths are hardcoded to 1000us/2000us respectively. 
+
+At the end of each loop, the entire array will be read, to flush any data that may cause issues later.
+
+Upcoming (TODO):
+- Use bit shift to allow 12 bits to be used for the duty cycle range, as there can only be a max of 16 channels anyway (4 bits).
+- Consider protobuf or msgpack for serialisation format, for more advanced use cases, and more maintainable communication formats (currently changing the message format will require changes to the entire protocol)
--- a/esp32/include/README
+++ b/esp32/include/README
@@ -0,0 +1,39 @@
+
+This directory is intended for project header files.
+
+A header file is a file containing C declarations and macro definitions
+to be shared between several project source files. You request the use of a
+header file in your project source file (C, C++, etc) located in `src` folder
+by including it, with the C preprocessing directive `#include'.
+
+```src/main.c
+
+#include "header.h"
+
+int main (void)
+{
+ ...
+}
+```
+
+Including a header file produces the same results as copying the header file
+into each source file that needs it. Such copying would be time-consuming
+and error-prone. With a header file, the related declarations appear
+in only one place. If they need to be changed, they can be changed in one
+place, and programs that include the header file will automatically use the
+new version when next recompiled. The header file eliminates the labor of
+finding and changing all the copies as well as the risk that a failure to
+find one copy will result in inconsistencies within a program.
+
+In C, the usual convention is to give header files names that end with `.h'.
+It is most portable to use only letters, digits, dashes, and underscores in
+header file names, and at most one dot.
+
+Read more about using header files in official GCC documentation:
+
+* Include Syntax
+* Include Operation
+* Once-Only Headers
+* Computed Includes
+
+https://gcc.gnu.org/onlinedocs/cpp/Header-Files.html
--- a/esp32/lib/README
+++ b/esp32/lib/README
@@ -0,0 +1,46 @@
+
+This directory is intended for project specific (private) libraries.
+PlatformIO will compile them to static libraries and link into executable file.
+
+The source code of each library should be placed in a an own separate directory
+("lib/your_library_name/[here are source files]").
+
+For example, see a structure of the following two libraries `Foo` and `Bar`:
+
+|--lib
+|  |
+|  |--Bar
+|  |  |--docs
+|  |  |--examples
+|  |  |--src
+|  |     |- Bar.c
+|  |     |- Bar.h
+|  |  |- library.json (optional, custom build options, etc) https://docs.platformio.org/page/librarymanager/config.html
+|  |
+|  |--Foo
+|  |  |- Foo.c
+|  |  |- Foo.h
+|  |
+|  |- README --> THIS FILE
+|
+|- platformio.ini
+|--src
+   |- main.c
+
+and a contents of `src/main.c`:
+```
+#include <Foo.h>
+#include <Bar.h>
+
+int main (void)
+{
+  ...
+}
+
+```
+
+PlatformIO Library Dependency Finder will find automatically dependent
+libraries scanning project source files.
+
+More information about PlatformIO Library Dependency Finder
+- https://docs.platformio.org/page/librarymanager/ldf.html
--- a/esp32/platformio.ini
+++ b/esp32/platformio.ini
@@ -0,0 +1,15 @@
+; PlatformIO Project Configuration File
+;
+;   Build options: build flags, source filter
+;   Upload options: custom upload port, speed and extra flags
+;   Library options: dependencies, extra library storages
+;   Advanced options: extra scripting
+;
+; Please visit documentation for the other options and examples
+; https://docs.platformio.org/page/projectconf.html
+
+[env:esp32doit-devkit-v1]
+platform = espressif32
+board = esp32doit-devkit-v1
+framework = arduino
+lib_deps = roboticsbrno/ServoESP32@^1.0.3
--- a/esp32/src/main.cpp
+++ b/esp32/src/main.cpp
@@ -0,0 +1,59 @@
+#include <Arduino.h>
+
+#include <map>
+#include "Servo.h"
+
+// Min/max widths, used to calculate min/max duty cycles.
+#define MIN_PULSE_WIDTH 1000
+#define MAX_PULSE_WIDTH 2000
+
+#define MIN_ANGLE 0
+#define MAX_ANGLE 255
+
+std::map<uint8_t, Servo *> servos;
+
+void setup()
+{
+    Serial.begin(115200);
+}
+
+void setupServos(uint8_t size, uint8_t *calibrationValues)
+{
+    // We assume there are 3 bytes per servo. Ignore if there aren't.
+    if (size % 3 == 0)
+    {
+        for (int i = 0; i < size; i += 2)
+        {
+            Servo *newServo = new Servo();
+            newServo->attach(calibrationValues[i + 1], calibrationValues[i], MIN_ANGLE, MAX_ANGLE, MIN_PULSE_WIDTH, MAX_PULSE_WIDTH);
+            servos.insert(std::make_pair(calibrationValues[i], newServo));
+        }
+    }
+}
+
+void modifyServo(uint8_t channel, uint8_t newAngle)
+{
+    if(servos.count(channel) > 0){
+        servos[channel]->write(newAngle);
+    } 
+}
+
+void loop()
+{
+    uint8_t *header = new uint8_t[2];
+    Serial.readBytes(header, 2);
+
+    if (header[0] == 0)
+    {
+        uint8_t *calibration = new uint8_t[2 * header[1]];
+        Serial.readBytes(calibration, header[1]);
+        setupServos(header[1], calibration);
+        delete [] calibration;
+    }
+    else
+    {
+        modifyServo(header[0], header[1]);
+    }
+
+    delete [] header;
+}
--- a/esp32/test/README
+++ b/esp32/test/README
@@ -0,0 +1,11 @@
+
+This directory is intended for PlatformIO Unit Testing and project tests.
+
+Unit Testing is a software testing method by which individual units of
+source code, sets of one or more MCU program modules together with associated
+control data, usage procedures, and operating procedures, are tested to
+determine whether they are fit for use. Unit testing finds problems early
+in the development cycle.
+
+More information about PlatformIO Unit Testing:
+- https://docs.platformio.org/page/plus/unit-testing.html
--- a/pycar/src/car/control/gpio/abstract_vehicle.py
+++ b/pycar/src/car/control/gpio/abstract_vehicle.py
@@ -0,0 +1,26 @@
+from abc import ABC, abstractmethod, abstractproperty
+
+class AbstractVehicle(ABC):
+    
+    @abstractmethod
+    @property
+    def throttle(self):
+        pass
+
+    @abstractmethod
+    @throttle.setter
+    def throttle(self):
+        pass
+
+    @abstractmethod
+    @property
+    def steering(self):
+        pass
+
+    @abstractmethod
+    @steering.setter
+    def throttle(self):
+        pass
+
+    def stop(self):
+        pass
--- a/pycar/src/car/control/gpio/factory.py
+++ b/pycar/src/car/control/gpio/factory.py
@@ -1,18 +1,25 @@
+from car.control.gpio.abstract_vehicle import AbstractVehicle
+from car.control.gpio.serial_vehicle import SerialVehicle
 from .mockvehicle import MockVehicle
 import os


-def get_vehicle(motor_pin=19, steering_pin=18):
+# TODO: Remove need for motor/steering pin, instead retrieve from env variable.
+# TODO: Dependency injectino in python?
+def get_vehicle(motor_pin=19, steering_pin=18) -> AbstractVehicle:
    ENV_CAR = None if 'CAR_VEHICLE' not in os.environ else os.environ['CAR_VEHICLE']
-    if ENV_CAR == "CAR_2D":
+    if ENV_CAR == "VEHICLE_2D":
        try:
            from .vehicle import Vehicle
            return Vehicle(motor_pin, steering_pin)
        except ImportError:
            print(
                'Could not import CAR_2D vehicle. Have you installed the GPIOZERO package?')
-    elif ENV_CAR == "CAR_MOCK":
-        return MockVehicle(motor_pin, steering_pin)
+    elif ENV_CAR == "VEHICLE_MOCK":
+        return MockVehicle()
+    elif ENV_CAR == "VEHICLE_SERIAL":
+        # TODO: Pins in environment variables.
+        return SerialVehicle()
    else:
        print('No valid vehicle found. Have you set the CAR_VEHICLE environment variable?')
        return None
--- a/pycar/src/car/control/gpio/mockvehicle.py
+++ b/pycar/src/car/control/gpio/mockvehicle.py
@@ -1,10 +1,11 @@


-# A dummy vehicle class to use when 
-class MockVehicle:
-    def __init__(self, motor_pin=19, servo_pin=18):
-        self.motor_pin = motor_pin
-        self.steering_pin = servo_pin
+# A dummy vehicle class to use when testing/not connected to a real device.
+from car.control.gpio.abstract_vehicle import AbstractVehicle
+
+
+class MockVehicle(AbstractVehicle):
+    def __init__(self):
        print('Using Mock Vehicle')

    @property
@@ -23,21 +24,5 @@ class MockVehicle:
    def steering(self, value):
        self._steering = value

-    @property
-    def motor_pin(self):
-        return self._motor_pin
-
-    @motor_pin.setter
-    def motor_pin(self, value):
-        self._motor_pin = value
-
-    @property
-    def steering_pin(self):
-        return self._steering_pin
-
-    @steering_pin.setter
-    def steering_pin(self, value):
-        self._steering_pin = value
-
    def stop(self):
        self.throttle = 0
--- a/pycar/src/car/control/gpio/recording_vehicle_decorator.py
+++ b/pycar/src/car/control/gpio/recording_vehicle_decorator.py
@@ -1,11 +1,12 @@
 import datetime
+from .abstract_vehicle import AbstractVehicle


-class VehicleRecordingDecorator:
+class VehicleRecordingDecorator(AbstractVehicle):
    def __init__(self, vehicle):
        """
        A decorator for a vehicle object to record the changes in steering/throttle.
-        This will be recorded to memory, and will save to the given file when save is called.
+        This will be recorded to memory, and will save to the given file when save_data is called.

        Parameters
        ----------
@@ -66,21 +67,5 @@ class VehicleRecordingDecorator:
                's,' + str(value) + ',' + datetime.datetime.now().isoformat(sep=' ', timespec='seconds'))
        self._vehicle.steering = value

-    @property
-    def motor_pin(self):
-        return self._vehicle.motor_pin
-
-    @motor_pin.setter
-    def motor_pin(self, value):
-        self._vehicle.motor_pin = value
-
-    @property
-    def steering_pin(self):
-        return self._vehicle.steering_pin
-
-    @steering_pin.setter
-    def steering_pin(self, value):
-        self._vehicle.steering_pin = value
-
    def stop(self):
        self.throttle = 0
--- a/pycar/src/car/control/gpio/serial_vehicle.py
+++ b/pycar/src/car/control/gpio/serial_vehicle.py
@@ -0,0 +1,42 @@
+from .abstract_vehicle import AbstractVehicle
+from serial import Serial
+
+STEERING_CHANNEL = 1
+THROTTLE_CHANNEL = 2
+
+
+class SerialVehicle(AbstractVehicle):
+
+    def __init__(self, serial_port='/dev/ttyUSB0', steering_pin=12, throttle_pin=14):
+        self.serial_port = Serial(port=serial_port, baudrate=115200)
+
+        # Initialise the channels and pins on esp32.
+        self._init_esp32_pwm(steering_pin, throttle_pin)
+        self.throttle = 0
+        self.steering = 0
+
+    @property
+    def throttle(self) -> float:
+        return self.throttle
+
+    @throttle.setter
+    def throttle(self, new_throttle: float):
+        self.throttle = new_throttle
+        self._set_servo_value(THROTTLE_CHANNEL, new_throttle)
+
+    @property
+    def steering(self) -> float:
+        return self.steering
+
+    @steering.setter
+    def steering(self, new_steering: float):
+        self.steering = new_steering
+        self._set_servo_value(STEERING_CHANNEL, new_steering)
+
+    def _set_servo_value(self, channel, value):
+        # Scale the value to a byte, as 0-255 is the angle range for the esp32 servo.
+        self.serial_port.write(bytes[channel, (value + 1) / 2 * 255])
+
+    def _init_esp32_pwm(self, steering_pin, throttle_pin):
+        self.serial_port.write(bytes([0, 2, STEERING_CHANNEL,
+                                      steering_pin, THROTTLE_CHANNEL, throttle_pin]))
--- a/pycar/src/car/control/gpio/vehicle.py
+++ b/pycar/src/car/control/gpio/vehicle.py
@@ -1,3 +1,4 @@
+from .abstract_vehicle import AbstractVehicle
 from gpiozero import Servo, Device
 from gpiozero.pins.pigpio import PiGPIOFactory
 import subprocess
@@ -29,7 +30,7 @@ def _is_pin_valid(pin):
 # two servos for controls (e.g. drone, dog)


-class Vehicle:
+class Vehicle(AbstractVehicle):
    def __init__(self, motor_pin=19, servo_pin=18):
        subprocess.call(['pigpiod'])
        Device.pin_factory = PiGPIOFactory()