├── .gitignore
├── .devcontainer
    ├── Dockerfile
    └── devcontainer.json
├── jetbot_control.xml
├── description
    ├── urdf
    │   └── jetbot.urdf.xacro
    └── ros2_control
    │   └── jetbot.ros2_control.xacro
├── package.xml
├── hardware
    ├── include
    │   └── jetbot_control
    │   │   ├── i2c_device.hpp
    │   │   ├── motor.hpp
    │   │   ├── visibility_control.h
    │   │   └── jetbot_system.hpp
    ├── src
    │   ├── motor.cpp
    │   ├── i2c_device.cpp
    │   └── jetbot_system.cpp
    └── test
    │   └── test_jetbot_system.cpp
├── LICENSE
├── bringup
    ├── config
    │   └── jetbot_controllers.yaml
    └── launch
    │   └── jetbot.launch.py
├── README.md
├── CMakeLists.txt
└── ROS2_CONTROL_LICENSE


/.gitignore:
--------------------------------------------------------------------------------
1 | build/
2 | install/
3 | log/
4 | .vscode/
5 | 


--------------------------------------------------------------------------------
/.devcontainer/Dockerfile:
--------------------------------------------------------------------------------
 1 | FROM ros:humble-ros-base
 2 | 
 3 | RUN apt update && \
 4 |     apt upgrade -y && \
 5 |     apt install -y \
 6 |         ros-humble-ros2-control \
 7 |         ros-humble-ros2-controllers \
 8 |         ros-humble-xacro \
 9 |         ros-humble-teleop-twist-keyboard \
10 |         gdb && \
11 |     apt clean
12 | 
13 | ENTRYPOINT /ros_entrypoint.sh
14 | 


--------------------------------------------------------------------------------
/jetbot_control.xml:
--------------------------------------------------------------------------------
 1 | <library path="jetbot_control">
 2 |   <class name="jetbot_control/JetBotSystemHardware"
 3 |          type="jetbot_control::JetBotSystemHardware"
 4 |          base_class_type="hardware_interface::SystemInterface">
 5 |     <description>
 6 |       The ros2_control system for driving a JetBot using I2C to move the motors.
 7 |     </description>
 8 |   </class>
 9 | </library>
10 | 


--------------------------------------------------------------------------------
/.devcontainer/devcontainer.json:
--------------------------------------------------------------------------------
 1 | {
 2 |   "name": "ROS2 Humble",
 3 |   "dockerFile": "Dockerfile",
 4 |   "runArgs": [
 5 |     "--privileged",
 6 |     "--network=host"
 7 |   ],
 8 |   "workspaceMount": "source=${localWorkspaceFolder},target=/${localWorkspaceFolderBasename},type=bind",
 9 |   "workspaceFolder": "/${localWorkspaceFolderBasename}",
10 |   "mounts": [
11 |     "source=${localEnv:HOME}${localEnv:USERPROFILE}/.bash_history,target=/home/vscode/.bash_history,type=bind"
12 |   ]
13 | }


--------------------------------------------------------------------------------
/description/urdf/jetbot.urdf.xacro:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0"?>
 2 | <robot xmlns:xacro="http://www.ros.org/wiki/xacro" name="diffdrive_robot">
 3 |   <xacro:arg name="prefix" default="" />
 4 |   <xacro:arg name="use_mock_hardware" default="false" />
 5 | 
 6 |   <xacro:include filename="$(find jetbot_control)/ros2_control/jetbot.ros2_control.xacro" />
 7 | 
 8 |   <xacro:jetbot_ros2_control
 9 |     name="JetBot" prefix="$(arg prefix)" use_mock_hardware="$(arg use_mock_hardware)"/>
10 | 
11 | </robot>
12 | 


--------------------------------------------------------------------------------
/package.xml:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0"?>
 2 | <?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
 3 | <package format="3">
 4 |   <name>jetbot_control</name>
 5 |   <version>0.0.0</version>
 6 |   <description>ROS2 Node for controlling a JetBot via ROS Control interfaces.</description>
 7 |   <maintainer email="mikelikesrobots@outlook.com">Mike Likes Robots</maintainer>
 8 |   <license>MIT</license>
 9 | 
10 |   <buildtool_depend>ament_cmake</buildtool_depend>
11 | 
12 |   <test_depend>ament_lint_auto</test_depend>
13 |   <test_depend>ament_lint_common</test_depend>
14 | 
15 |   <depend>rclcpp</depend>
16 | 
17 |   <export>
18 |     <build_type>ament_cmake</build_type>
19 |   </export>
20 | </package>
21 | 


--------------------------------------------------------------------------------
/hardware/include/jetbot_control/i2c_device.hpp:
--------------------------------------------------------------------------------
 1 | #ifndef JETBOT_CONTROL__I2C_DEVICE_HPP_
 2 | #define JETBOT_CONTROL__I2C_DEVICE_HPP_
 3 | 
 4 | #include <cstdint>
 5 | #include <mutex>
 6 | #include <optional>
 7 | 
 8 | namespace jetbot_control {
 9 | 
10 | class I2CDevice {
11 |  public:
12 |   I2CDevice();
13 |   ~I2CDevice();
14 |   bool tryEnableMotor(uint8_t pin);
15 |   bool trySetDutyCycle(uint8_t pin, uint16_t duty_cycle);
16 | 
17 |  private:
18 |   bool trySelectDevice();
19 |   bool tryWriteReg(uint8_t reg, uint8_t data);
20 |   std::optional<uint8_t> tryReadReg(uint8_t reg);
21 |   bool trySetClock();
22 |   bool tryReset();
23 |   int i2c_fd_;
24 |   uint8_t buf_[10];
25 | };
26 | 
27 | }  // namespace jetbot_control
28 | 
29 | #endif  // JETBOT_CONTROL__I2C_DEVICE_HPP_
30 | 


--------------------------------------------------------------------------------
/hardware/include/jetbot_control/motor.hpp:
--------------------------------------------------------------------------------
 1 | #pragma once
 2 | 
 3 | #ifndef JETBOT_CONTROL__MOTOR_HPP_
 4 | #define JETBOT_CONTROL__MOTOR_HPP_
 5 | 
 6 | #include <memory>
 7 | #include <tuple>
 8 | 
 9 | #include "jetbot_control/i2c_device.hpp"
10 | 
11 | using u8 = uint8_t;
12 | using I2CDevicePtr = std::shared_ptr<jetbot_control::I2CDevice>;
13 | using MotorPins = std::tuple<u8, u8, u8>;
14 | 
15 | namespace jetbot_control {
16 | class Motor {
17 |  public:
18 |   Motor() = default;
19 |   Motor(I2CDevicePtr i2c, MotorPins pins, std::string name);
20 |   ~Motor();
21 |   bool trySetVelocity(double velocity);
22 | 
23 |  private:
24 |   I2CDevicePtr i2c_;
25 |   MotorPins pins_;
26 |   std::string name_;
27 | };
28 | }  // namespace jetbot_control
29 | 
30 | #endif  // JETBOT_CONTROL__MOTOR_HPP_
31 | 


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
 1 | MIT License
 2 | 
 3 | Copyright (c) 2024 mikelikesrobots
 4 | 
 5 | Permission is hereby granted, free of charge, to any person obtaining a copy
 6 | of this software and associated documentation files (the "Software"), to deal
 7 | in the Software without restriction, including without limitation the rights
 8 | to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 9 | copies of the Software, and to permit persons to whom the Software is
10 | furnished to do so, subject to the following conditions:
11 | 
12 | The above copyright notice and this permission notice shall be included in all
13 | copies or substantial portions of the Software.
14 | 
15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 | FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 | AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 | LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 | OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 | SOFTWARE.
22 | 


--------------------------------------------------------------------------------
/description/ros2_control/jetbot.ros2_control.xacro:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0"?>
 2 | <robot xmlns:xacro="http://www.ros.org/wiki/xacro">
 3 | 
 4 |   <xacro:macro name="jetbot_ros2_control" params="name prefix use_mock_hardware">
 5 | 
 6 |     <ros2_control name="${name}" type="system">
 7 |       <xacro:unless value="${use_mock_hardware}">
 8 |         <hardware>
 9 |           <plugin>jetbot_control/JetBotSystemHardware</plugin>
10 |           <param name="pin_enable_0">8</param>
11 |           <param name="pin_pos_0">9</param>
12 |           <param name="pin_neg_0">10</param>
13 |           <param name="pin_enable_1">13</param>
14 |           <param name="pin_pos_1">12</param>
15 |           <param name="pin_neg_1">11</param>
16 |         </hardware>
17 |       </xacro:unless>
18 |       <xacro:if value="${use_mock_hardware}">
19 |         <hardware>
20 |           <plugin>mock_components/GenericSystem</plugin>
21 |           <param name="calculate_dynamics">true</param>
22 |         </hardware>
23 |       </xacro:if>
24 |       <joint name="${prefix}left_wheel_joint">
25 |         <command_interface name="velocity"/>
26 |         <state_interface name="velocity"/>
27 |       </joint>
28 |       <joint name="${prefix}right_wheel_joint">
29 |         <command_interface name="velocity"/>
30 |         <state_interface name="velocity"/>
31 |       </joint>
32 |     </ros2_control>
33 | 
34 |   </xacro:macro>
35 | 
36 | </robot>
37 | 


--------------------------------------------------------------------------------
/hardware/src/motor.cpp:
--------------------------------------------------------------------------------
 1 | #include "jetbot_control/motor.hpp"
 2 | 
 3 | using namespace jetbot_control;
 4 | 
 5 | #include <algorithm>
 6 | #include <cmath>
 7 | #include <iostream>
 8 | #include <string>
 9 | 
10 | Motor::Motor(I2CDevicePtr i2c, MotorPins pins, std::string name)
11 |     : i2c_{i2c}, pins_{pins}, name_{name} {
12 |   u8 enable_pin = std::get<0>(pins_);
13 |   if (!i2c_->tryEnableMotor(enable_pin)) {
14 |     std::string error = "Failed to enable motor " + name_ + "!";
15 |     std::__throw_runtime_error(error.c_str());
16 |   }
17 | }
18 | 
19 | Motor::~Motor() { trySetVelocity(0); }
20 | 
21 | bool Motor::trySetVelocity(double velocity) {
22 |   u8 pos_pin = std::get<1>(pins_);
23 |   u8 neg_pin = std::get<2>(pins_);
24 | 
25 |   // Interpret <1/1000 max speed as not spinning
26 |   if (std::fabs(velocity) < 0.001) {
27 |     if (!i2c_->trySetDutyCycle(pos_pin, 0xFFFF)) {
28 |       return false;
29 |     }
30 |     if (!i2c_->trySetDutyCycle(neg_pin, 0xFFFF)) {
31 |       return false;
32 |     }
33 |     return true;
34 |   }
35 | 
36 |   uint16_t duty_cycle = 0xFFFF * std::fabs(velocity);
37 | 
38 |   // Use braking mode
39 |   if (velocity > 0) {
40 |     if (!i2c_->trySetDutyCycle(pos_pin, 0xFFFF)) {
41 |       return false;
42 |     }
43 |     if (!i2c_->trySetDutyCycle(neg_pin, 0xFFFF - duty_cycle)) {
44 |       return false;
45 |     }
46 |   } else {
47 |     if (!i2c_->trySetDutyCycle(pos_pin, 0xFFFF - duty_cycle)) {
48 |       return false;
49 |     }
50 |     if (!i2c_->trySetDutyCycle(neg_pin, 0xFFFF)) {
51 |       return false;
52 |     }
53 |   }
54 | 
55 |   return true;
56 | }
57 | 


--------------------------------------------------------------------------------
/hardware/test/test_jetbot_system.cpp:
--------------------------------------------------------------------------------
 1 | #include <gmock/gmock.h>
 2 | 
 3 | #include "hardware_interface/resource_manager.hpp"
 4 | #include "ros2_control_test_assets/components_urdfs.hpp"
 5 | #include "ros2_control_test_assets/descriptions.hpp"
 6 | 
 7 | class TestJetBotSystem : public ::testing::Test {
 8 |  protected:
 9 |   void SetUp() override {
10 |     mock_system_ =
11 |         R"(
12 |   <ros2_control name="MockJetBotSystemHardware" type="system">
13 |     <hardware>
14 |       <plugin>jetbot_control/JetBotSystemHardware</plugin>
15 |       <param name="pin_enable_0">1</param>
16 |       <param name="pin_pos_0">2</param>
17 |       <param name="pin_neg_0">3</param>
18 |       <param name="pin_enable_1">4</param>
19 |       <param name="pin_pos_1">5</param>
20 |       <param name="pin_neg_1">6</param>
21 |     </hardware>
22 |   </ros2_control>
23 | )";
24 |   }
25 | 
26 |   std::string mock_system_;
27 | };
28 | 
29 | class TestableResourceManager : public hardware_interface::ResourceManager {
30 |  public:
31 |   friend TestJetBotSystem;
32 |   TestableResourceManager() : hardware_interface::ResourceManager() {}
33 |   TestableResourceManager(const std::string& urdf,
34 |                           bool validate_interfaces = true,
35 |                           bool activate_all = false)
36 |       : hardware_interface::ResourceManager(urdf, validate_interfaces,
37 |                                             activate_all) {}
38 | };
39 | 
40 | TEST_F(TestJetBotSystem, load_generic_system) {
41 |   auto urdf = ros2_control_test_assets::urdf_head + mock_system_ +
42 |               ros2_control_test_assets::urdf_tail;
43 |   ASSERT_NO_THROW(TestableResourceManager rm(urdf));
44 | }
45 | 


--------------------------------------------------------------------------------
/bringup/config/jetbot_controllers.yaml:
--------------------------------------------------------------------------------
 1 | controller_manager:
 2 |   ros__parameters:
 3 |     update_rate: 10  # Hz
 4 | 
 5 |     jetbot_base_controller:
 6 |       type: diff_drive_controller/DiffDriveController
 7 | 
 8 | jetbot_base_controller:
 9 |   ros__parameters:
10 |     left_wheel_names: ["left_wheel_joint"]
11 |     right_wheel_names: ["right_wheel_joint"]
12 | 
13 |     wheel_separation: 0.104
14 |     #wheels_per_side: 1
15 |     wheel_radius: 0.032
16 | 
17 |     wheel_separation_multiplier: 1.0
18 |     left_wheel_radius_multiplier: 1.0
19 |     right_wheel_radius_multiplier: 1.0
20 | 
21 |     publish_rate: 50.0
22 |     odom_frame_id: odom
23 |     base_frame_id: base_link
24 |     pose_covariance_diagonal : [0.001, 0.001, 0.001, 0.001, 0.001, 0.01]
25 |     twist_covariance_diagonal: [0.001, 0.001, 0.001, 0.001, 0.001, 0.01]
26 | 
27 |     open_loop: true
28 |     position_feedback: false
29 |     enable_odom_tf: true
30 | 
31 |     cmd_vel_timeout: 0.5
32 |     #publish_limited_velocity: true
33 |     #velocity_rolling_window_size: 10
34 | 
35 |     # Velocity and acceleration limits
36 |     # Whenever a min_* is unspecified, default to -max_*
37 |     linear.x.has_velocity_limits: true
38 |     linear.x.has_acceleration_limits: true
39 |     linear.x.has_jerk_limits: false
40 |     linear.x.max_velocity: 0.016
41 |     linear.x.min_velocity: -0.016
42 |     linear.x.max_acceleration: 0.07
43 |     linear.x.max_jerk: 0.0
44 |     linear.x.min_jerk: 0.0
45 | 
46 |     angular.z.has_velocity_limits: true
47 |     angular.z.has_acceleration_limits: true
48 |     angular.z.has_jerk_limits: false
49 |     angular.z.max_velocity: 0.25
50 |     angular.z.min_velocity: -0.25
51 |     angular.z.max_acceleration: 1.0
52 |     angular.z.min_acceleration: -1.0
53 |     angular.z.max_jerk: 0.0
54 |     angular.z.min_jerk: 0.0
55 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | # JetBot ROS Control
 2 | 
 3 | ROS2 Node for controlling a JetBot via ROS Control interfaces.
 4 | 
 5 | ## Setup
 6 | 
 7 | From a WaveShare JetBot robot, clone this repository and open it over SSH. Install the Dev Containers extension and allow it to build the Docker container and open the workspace in that container.
 8 | 
 9 | Then build the code using `colcon build` from the workspace root:
10 | 
11 | ```bash
12 | source /opt/ros/humble/setup.bash
13 | colcon build
14 | ```
15 | 
16 | ## Testing the code
17 | 
18 | Once built, you can run the test function to check that the library can be loaded correctly as follows:
19 | 
20 | ```bash
21 | source install/setup.bash
22 | ./build/jetbot_control/test_jetbot_system
23 | ```
24 | 
25 | The test should pass with log messages showing a successful initialization of the control library.
26 | 
27 | ## Running the code
28 | 
29 | Once built, it should be possible to launch the jetbot controller using the provided launch file. Note that this will only run on a JetBot with the i2c-1 bus available.
30 | 
31 | ```bash
32 | source install/setup.bash
33 | ros2 launch jetbot_control jetbot.launch.py
34 | ```
35 | 
36 | After this, the robot will respond to commands sent with `TwistStamped` type sent on the `/cmd_vel` topic.
37 | 
38 | If you want to run mock hardware for any reason, such as not having a JetBot to run the code on, you can enable the flag as follows:
39 | 
40 | ```bash
41 | ros2 launch jetbot_control jetbot.launch.py use_mock_hardware:=true
42 | ```
43 | 
44 | ## License
45 | 
46 | The code in this repository is covered by the MIT license in the [LICENSE](./LICENSE) file. However, four files are included from the [ros2_control_demos](https://github.com/ros-controls/ros2_control_demos) repository, and so are covered by the [ROS2_CONTROL_LICENSE](./ROS2_CONTROL_LICENSE) file instead. These four files are as follows:
47 | 
48 | 1. [jetbot.launch.py](./bringup/launch/jetbot.launch.py)
49 | 2. [jetbot_system.cpp](./hardware/src/jetbot_system.cpp)
50 | 3. [jetbot_system.hpp](./hardware/include/jetbot_control/jetbot_system.hpp)
51 | 4. [visibility_control.h](./hardware/include/jetbot_control/visibility_control.h)
52 | 


--------------------------------------------------------------------------------
/CMakeLists.txt:
--------------------------------------------------------------------------------
 1 | cmake_minimum_required(VERSION 3.8)
 2 | project(jetbot_control LANGUAGES CXX)
 3 | 
 4 | if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
 5 |   add_compile_options(-Wall -Wextra -Wpedantic)
 6 | endif()
 7 | 
 8 | set(THIS_PACKAGE_INCLUDE_DEPENDS
 9 |   hardware_interface
10 |   pluginlib
11 |   rclcpp
12 |   rclcpp_lifecycle
13 | )
14 | 
15 | find_package(ament_cmake REQUIRED)
16 | foreach(Dependency IN ITEMS ${THIS_PACKAGE_INCLUDE_DEPENDS})
17 |   find_package(${Dependency} REQUIRED)
18 | endforeach()
19 | 
20 | add_library(${PROJECT_NAME}
21 |   SHARED
22 |   hardware/src/jetbot_system.cpp
23 |   hardware/src/i2c_device.cpp
24 |   hardware/src/motor.cpp
25 | )
26 | target_compile_features(${PROJECT_NAME} PUBLIC cxx_std_20)
27 | target_include_directories(${PROJECT_NAME} PUBLIC
28 | $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/hardware/include>
29 | $<INSTALL_INTERFACE:include/jetbot_control>
30 | )
31 | ament_target_dependencies(
32 |   ${PROJECT_NAME} PUBLIC
33 |   ${THIS_PACKAGE_INCLUDE_DEPENDS}
34 | )
35 | 
36 | # Causes the visibility macros to use dllexport rather than dllimport,
37 | # which is appropriate when building the dll but not consuming it.
38 | target_compile_definitions(${PROJECT_NAME} PRIVATE "JETBOT_CONTROL_BUILDING_DLL")
39 | 
40 | pluginlib_export_plugin_description_file(hardware_interface jetbot_control.xml)
41 | 
42 | install(
43 |   DIRECTORY hardware/include/
44 |   DESTINATION include/jetbot_control
45 | )
46 | install(
47 |   DIRECTORY description/ros2_control description/urdf
48 |   DESTINATION share/jetbot_control
49 | )
50 | install(
51 |   DIRECTORY bringup/launch bringup/config
52 |   DESTINATION share/jetbot_control
53 | )
54 | 
55 | install(TARGETS
56 |   ${PROJECT_NAME}
57 |   EXPORT export_jetbot_control
58 |   ARCHIVE DESTINATION lib
59 |   LIBRARY DESTINATION lib
60 |   RUNTIME DESTINATION bin
61 | )
62 | 
63 | if(BUILD_TESTING)
64 |   find_package(ament_cmake_gmock REQUIRED)
65 |   find_package(ros2_control_test_assets REQUIRED)
66 |   ament_add_gmock(test_jetbot_system hardware/test/test_jetbot_system.cpp)
67 |   target_include_directories(test_jetbot_system PRIVATE include)
68 |   target_link_libraries(test_jetbot_system ${PROJECT_NAME})
69 |   ament_target_dependencies(test_jetbot_system
70 |     pluginlib
71 |     ros2_control_test_assets
72 |   )
73 | endif()
74 | 
75 | ament_export_targets(export_jetbot_control HAS_LIBRARY_TARGET)
76 | ament_export_dependencies(${THIS_PACKAGE_INCLUDE_DEPENDS})
77 | ament_package()
78 | 


--------------------------------------------------------------------------------
/hardware/include/jetbot_control/visibility_control.h:
--------------------------------------------------------------------------------
 1 | // Copyright 2021 ros2_control Development Team
 2 | //
 3 | // Licensed under the Apache License, Version 2.0 (the "License");
 4 | // you may not use this file except in compliance with the License.
 5 | // You may obtain a copy of the License at
 6 | //
 7 | //     http://www.apache.org/licenses/LICENSE-2.0
 8 | //
 9 | // Unless required by applicable law or agreed to in writing, software
10 | // distributed under the License is distributed on an "AS IS" BASIS,
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 | // See the License for the specific language governing permissions and
13 | // limitations under the License.
14 | //
15 | // This file was last modified by Michael Hart, a.k.a Mike Likes Robots
16 | // (mikelikesrobots@outlook.com), on 2024-03-07.
17 | 
18 | /* This header must be included by all rclcpp headers which declare symbols
19 |  * which are defined in the rclcpp library. When not building the rclcpp
20 |  * library, i.e. when using the headers in other package's code, the contents
21 |  * of this header change the visibility of certain symbols which the rclcpp
22 |  * library cannot have, but the consuming code must have inorder to link.
23 |  */
24 | 
25 | #ifndef JETBOT_CONTROL__VISIBILITY_CONTROL_H_
26 | #define JETBOT_CONTROL__VISIBILITY_CONTROL_H_
27 | 
28 | // This logic was borrowed (then namespaced) from the examples on the gcc wiki:
29 | //     https://gcc.gnu.org/wiki/Visibility
30 | 
31 | #if defined _WIN32 || defined __CYGWIN__
32 | #ifdef __GNUC__
33 | #define JETBOT_CONTROL_EXPORT __attribute__((dllexport))
34 | #define JETBOT_CONTROL_IMPORT __attribute__((dllimport))
35 | #else
36 | #define JETBOT_CONTROL_EXPORT __declspec(dllexport)
37 | #define JETBOT_CONTROL_IMPORT __declspec(dllimport)
38 | #endif
39 | #ifdef JETBOT_CONTROL_BUILDING_DLL
40 | #define JETBOT_CONTROL_PUBLIC JETBOT_CONTROL_EXPORT
41 | #else
42 | #define JETBOT_CONTROL_PUBLIC JETBOT_CONTROL_IMPORT
43 | #endif
44 | #define JETBOT_CONTROL_PUBLIC_TYPE JETBOT_CONTROL_PUBLIC
45 | #define JETBOT_CONTROL_LOCAL
46 | #else
47 | #define JETBOT_CONTROL_EXPORT __attribute__((visibility("default")))
48 | #define JETBOT_CONTROL_IMPORT
49 | #if __GNUC__ >= 4
50 | #define JETBOT_CONTROL_PUBLIC __attribute__((visibility("default")))
51 | #define JETBOT_CONTROL_LOCAL __attribute__((visibility("hidden")))
52 | #else
53 | #define JETBOT_CONTROL_PUBLIC
54 | #define JETBOT_CONTROL_LOCAL
55 | #endif
56 | #define JETBOT_CONTROL_PUBLIC_TYPE
57 | #endif
58 | 
59 | #endif  // JETBOT_CONTROL__VISIBILITY_CONTROL_H_
60 | 


--------------------------------------------------------------------------------
/bringup/launch/jetbot.launch.py:
--------------------------------------------------------------------------------
 1 | # Copyright 2020 ros2_control Development Team
 2 | #
 3 | # Licensed under the Apache License, Version 2.0 (the "License");
 4 | # you may not use this file except in compliance with the License.
 5 | # You may obtain a copy of the License at
 6 | #
 7 | #     http://www.apache.org/licenses/LICENSE-2.0
 8 | #
 9 | # Unless required by applicable law or agreed to in writing, software
10 | # distributed under the License is distributed on an "AS IS" BASIS,
11 | # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 | # See the License for the specific language governing permissions and
13 | # limitations under the License.
14 | #
15 | # This file was last modified by Michael Hart, a.k.a Mike Likes Robots
16 | # (mikelikesrobots@outlook.com), on 2024-03-07.
17 | 
18 | from launch import LaunchDescription
19 | from launch.actions import DeclareLaunchArgument, RegisterEventHandler
20 | from launch.conditions import IfCondition
21 | from launch.event_handlers import OnProcessExit
22 | from launch.substitutions import (
23 |     Command,
24 |     FindExecutable,
25 |     PathJoinSubstitution,
26 |     LaunchConfiguration,
27 | )
28 | 
29 | from launch_ros.actions import Node
30 | from launch_ros.substitutions import FindPackageShare
31 | 
32 | 
33 | def generate_launch_description():
34 |     # Declare arguments
35 |     declared_arguments = []
36 |     declared_arguments.append(
37 |         DeclareLaunchArgument(
38 |             "use_mock_hardware",
39 |             default_value="false",
40 |             description="Start robot with mock hardware mirroring command to its states.",
41 |         )
42 |     )
43 | 
44 |     # Initialize Arguments
45 |     use_mock_hardware = LaunchConfiguration("use_mock_hardware")
46 | 
47 |     # Get URDF via xacro
48 |     robot_description_content = Command(
49 |         [
50 |             PathJoinSubstitution([FindExecutable(name="xacro")]),
51 |             " ",
52 |             PathJoinSubstitution(
53 |                 [FindPackageShare("jetbot_control"), "urdf", "jetbot.urdf.xacro"]
54 |             ),
55 |             " ",
56 |             "use_mock_hardware:=",
57 |             use_mock_hardware,
58 |         ]
59 |     )
60 |     robot_description = {"robot_description": robot_description_content}
61 | 
62 |     robot_controllers = PathJoinSubstitution(
63 |         [
64 |             FindPackageShare("jetbot_control"),
65 |             "config",
66 |             "jetbot_controllers.yaml",
67 |         ]
68 |     )
69 | 
70 |     control_node = Node(
71 |         package="controller_manager",
72 |         executable="ros2_control_node",
73 |         parameters=[robot_description, robot_controllers],
74 |         output="both",
75 |     )
76 |     robot_controller_spawner = Node(
77 |         package="controller_manager",
78 |         executable="spawner",
79 |         arguments=[
80 |             "jetbot_base_controller",
81 |             "--controller-manager",
82 |             "/controller_manager",
83 |         ],
84 |     )
85 | 
86 |     nodes = [
87 |         control_node,
88 |         robot_controller_spawner,
89 |     ]
90 | 
91 |     return LaunchDescription(declared_arguments + nodes)
92 | 


--------------------------------------------------------------------------------
/hardware/include/jetbot_control/jetbot_system.hpp:
--------------------------------------------------------------------------------
 1 | // Copyright 2021 ros2_control Development Team
 2 | //
 3 | // Licensed under the Apache License, Version 2.0 (the "License");
 4 | // you may not use this file except in compliance with the License.
 5 | // You may obtain a copy of the License at
 6 | //
 7 | //     http://www.apache.org/licenses/LICENSE-2.0
 8 | //
 9 | // Unless required by applicable law or agreed to in writing, software
10 | // distributed under the License is distributed on an "AS IS" BASIS,
11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 | // See the License for the specific language governing permissions and
13 | // limitations under the License.
14 | //
15 | // This file was last modified by Michael Hart, a.k.a Mike Likes Robots
16 | // (mikelikesrobots@outlook.com), on 2024-03-07.
17 | 
18 | #ifndef JETBOT_CONTROL__JETBOT_SYSTEM_HPP_
19 | #define JETBOT_CONTROL__JETBOT_SYSTEM_HPP_
20 | 
21 | #include <memory>
22 | #include <string>
23 | #include <vector>
24 | 
25 | #include "hardware_interface/handle.hpp"
26 | #include "hardware_interface/hardware_info.hpp"
27 | #include "hardware_interface/system_interface.hpp"
28 | #include "hardware_interface/types/hardware_interface_return_values.hpp"
29 | #include "jetbot_control/i2c_device.hpp"
30 | #include "jetbot_control/motor.hpp"
31 | #include "jetbot_control/visibility_control.h"
32 | #include "rclcpp/clock.hpp"
33 | #include "rclcpp/duration.hpp"
34 | #include "rclcpp/macros.hpp"
35 | #include "rclcpp/time.hpp"
36 | #include "rclcpp_lifecycle/node_interfaces/lifecycle_node_interface.hpp"
37 | #include "rclcpp_lifecycle/state.hpp"
38 | 
39 | namespace jetbot_control {
40 | class JetBotSystemHardware : public hardware_interface::SystemInterface {
41 |  public:
42 |   RCLCPP_SHARED_PTR_DEFINITIONS(JetBotSystemHardware)
43 | 
44 |   JETBOT_CONTROL_PUBLIC
45 |   hardware_interface::CallbackReturn on_init(
46 |       const hardware_interface::HardwareInfo& info) override;
47 | 
48 |   JETBOT_CONTROL_PUBLIC
49 |   std::vector<hardware_interface::StateInterface> export_state_interfaces()
50 |       override;
51 | 
52 |   JETBOT_CONTROL_PUBLIC
53 |   std::vector<hardware_interface::CommandInterface> export_command_interfaces()
54 |       override;
55 | 
56 |   JETBOT_CONTROL_PUBLIC
57 |   hardware_interface::CallbackReturn on_activate(
58 |       const rclcpp_lifecycle::State& previous_state) override;
59 | 
60 |   JETBOT_CONTROL_PUBLIC
61 |   hardware_interface::CallbackReturn on_deactivate(
62 |       const rclcpp_lifecycle::State& previous_state) override;
63 | 
64 |   JETBOT_CONTROL_PUBLIC
65 |   hardware_interface::return_type read(const rclcpp::Time& time,
66 |                                        const rclcpp::Duration& period) override;
67 | 
68 |   JETBOT_CONTROL_PUBLIC
69 |   hardware_interface::return_type write(
70 |       const rclcpp::Time& time, const rclcpp::Duration& period) override;
71 | 
72 |  private:
73 |   std::vector<MotorPins> motor_pin_sets_;
74 |   std::vector<Motor> motors_;
75 |   std::shared_ptr<I2CDevice> i2c_device_;
76 |   std::vector<double> hw_commands_;
77 |   std::vector<double> hw_velocities_;
78 | };
79 | 
80 | }  // namespace jetbot_control
81 | 
82 | #endif  // JETBOT_CONTROL__JETBOT_SYSTEM_HPP_
83 | 


--------------------------------------------------------------------------------
/hardware/src/i2c_device.cpp:
--------------------------------------------------------------------------------
  1 | #include "jetbot_control/i2c_device.hpp"
  2 | 
  3 | #include <fcntl.h>
  4 | #include <linux/i2c-dev.h>
  5 | #include <linux/i2c.h>
  6 | #include <linux/types.h>
  7 | #include <sys/ioctl.h>
  8 | #include <unistd.h>
  9 | 
 10 | #include <cstdio>
 11 | #include <iostream>
 12 | #include <thread>
 13 | 
 14 | const uint8_t kDefaultDeviceAddress = 0x60;
 15 | const uint8_t kMode1Reg = 0x00;
 16 | const uint8_t kMode2Reg = 0x01;
 17 | const uint8_t kPrescaleReg = 0xFE;
 18 | const uint8_t kPwmReg = 0x06;
 19 | const float kReferenceClockSpeed = 25e6;
 20 | const float kPwmFrequency = 1600.0;
 21 | 
 22 | using namespace std::chrono_literals;
 23 | using namespace jetbot_control;
 24 | 
 25 | I2CDevice::I2CDevice() {
 26 |   i2c_fd_ = open("/dev/i2c-1", O_RDWR);
 27 |   if (!i2c_fd_) {
 28 |     std::__throw_runtime_error("Failed to open I2C interface!");
 29 |   }
 30 | 
 31 |   // Select the PWM device
 32 |   if (!trySelectDevice())
 33 |     std::__throw_runtime_error("Failed to select PWM device!");
 34 | 
 35 |   // Reset the PWM device
 36 |   if (!tryReset()) std::__throw_runtime_error("Failed to reset PWM device!");
 37 | 
 38 |   // Set the PWM device clock
 39 |   if (!trySetClock()) std::__throw_runtime_error("Failed to set PWM clock!");
 40 | }
 41 | 
 42 | I2CDevice::~I2CDevice() {
 43 |   tryReset();
 44 |   if (i2c_fd_) {
 45 |     close(i2c_fd_);
 46 |   }
 47 | }
 48 | 
 49 | bool I2CDevice::tryEnableMotor(uint8_t pin) {
 50 |   buf_[0] = kPwmReg + 4 * pin;
 51 |   buf_[1] = 0x00;
 52 |   buf_[2] = 0x10;
 53 |   buf_[3] = 0x00;
 54 |   buf_[4] = 0x00;
 55 |   return write(i2c_fd_, buf_, 5) == 5;
 56 | }
 57 | 
 58 | bool I2CDevice::trySetDutyCycle(uint8_t pin, uint16_t duty_cycle) {
 59 |   buf_[0] = kPwmReg + 4 * pin;
 60 | 
 61 |   if (duty_cycle == 0xFFFF) {
 62 |     // Special case - fully on
 63 |     buf_[1] = 0x00;
 64 |     buf_[2] = 0x10;
 65 |     buf_[3] = 0x00;
 66 |     buf_[4] = 0x00;
 67 |   } else if (duty_cycle < 0x0010) {
 68 |     // Special case - fully off
 69 |     buf_[1] = 0x00;
 70 |     buf_[2] = 0x00;
 71 |     buf_[3] = 0x00;
 72 |     buf_[4] = 0x10;
 73 |   } else {
 74 |     // Shift by 4 to fit 12-bit register
 75 |     uint16_t value = duty_cycle >> 4;
 76 |     buf_[1] = (uint8_t)0;
 77 |     buf_[2] = (uint8_t)0;
 78 |     buf_[3] = (uint8_t)(value & 0xFF);
 79 |     buf_[4] = (uint8_t)((value >> 8) & 0xFF);
 80 |   }
 81 | 
 82 |   return write(i2c_fd_, buf_, 5) == 5;
 83 | }
 84 | 
 85 | bool I2CDevice::tryWriteReg(uint8_t reg, uint8_t data) {
 86 |   buf_[0] = reg;
 87 |   buf_[1] = data;
 88 |   return write(i2c_fd_, buf_, 2) == 2;
 89 | }
 90 | std::optional<uint8_t> I2CDevice::tryReadReg(uint8_t reg) {
 91 |   buf_[0] = reg;
 92 |   if (write(i2c_fd_, buf_, 1) != 1) {
 93 |     return std::nullopt;
 94 |   }
 95 |   if (read(i2c_fd_, buf_, 1) != 1) {
 96 |     return std::nullopt;
 97 |   }
 98 |   return buf_[0];
 99 | }
100 | 
101 | bool I2CDevice::trySetClock() {
102 |   const uint8_t prescale =
103 |       (kReferenceClockSpeed / 4096.0 / kPwmFrequency + 0.5) - 1;
104 |   if (prescale < 3) return false;
105 | 
106 |   // Read old mode
107 |   const auto old_mode_op = tryReadReg(kMode1Reg);
108 |   if (!old_mode_op.has_value()) return false;
109 |   const uint8_t old_mode = *old_mode_op;
110 | 
111 |   // Set a new mode/prescaler, then sleep
112 |   const uint8_t new_mode = (old_mode & 0x7F) | 0x10;
113 |   if (!tryWriteReg(kMode1Reg, new_mode)) return false;
114 |   if (!tryWriteReg(kPrescaleReg, prescale)) return false;
115 |   if (!tryWriteReg(kMode1Reg, old_mode)) return false;
116 |   std::this_thread::sleep_for(5ms);
117 | 
118 |   // Set mode 1 with autoincrement, fix to stop pca9685 from accepting commands
119 |   // at all addresses
120 |   if (!tryWriteReg(kMode1Reg, old_mode | 0xA0)) return false;
121 | 
122 |   return true;
123 | }
124 | 
125 | bool I2CDevice::tryReset() { return tryWriteReg(kMode1Reg, 0x00); }
126 | 
127 | bool I2CDevice::trySelectDevice() {
128 |   return ioctl(i2c_fd_, I2C_SLAVE, kDefaultDeviceAddress) >= 0;
129 | }
130 | 


--------------------------------------------------------------------------------
/hardware/src/jetbot_system.cpp:
--------------------------------------------------------------------------------
  1 | // Copyright 2021 ros2_control Development Team
  2 | //
  3 | // Licensed under the Apache License, Version 2.0 (the "License");
  4 | // you may not use this file except in compliance with the License.
  5 | // You may obtain a copy of the License at
  6 | //
  7 | //     http://www.apache.org/licenses/LICENSE-2.0
  8 | //
  9 | // Unless required by applicable law or agreed to in writing, software
 10 | // distributed under the License is distributed on an "AS IS" BASIS,
 11 | // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 12 | // See the License for the specific language governing permissions and
 13 | // limitations under the License.
 14 | //
 15 | // This file was last modified by Michael Hart, a.k.a Mike Likes Robots
 16 | // (mikelikesrobots@outlook.com), on 2024-03-07.
 17 | 
 18 | #include "jetbot_control/jetbot_system.hpp"
 19 | 
 20 | #include <chrono>
 21 | #include <cmath>
 22 | #include <cstddef>
 23 | #include <limits>
 24 | #include <memory>
 25 | #include <vector>
 26 | 
 27 | #include "hardware_interface/types/hardware_interface_type_values.hpp"
 28 | #include "rclcpp/rclcpp.hpp"
 29 | 
 30 | using namespace jetbot_control;
 31 | 
 32 | hardware_interface::CallbackReturn JetBotSystemHardware::on_init(
 33 |     const hardware_interface::HardwareInfo &info) {
 34 |   if (hardware_interface::SystemInterface::on_init(info) !=
 35 |       hardware_interface::CallbackReturn::SUCCESS) {
 36 |     return hardware_interface::CallbackReturn::ERROR;
 37 |   }
 38 | 
 39 |   hw_velocities_.resize(info_.joints.size(),
 40 |                         std::numeric_limits<double>::quiet_NaN());
 41 |   hw_commands_.resize(info_.joints.size(),
 42 |                       std::numeric_limits<double>::quiet_NaN());
 43 | 
 44 |   for (auto i = 0u; i < info_.joints.size(); i++) {
 45 |     auto pin_en_ =
 46 |         stoi(info_.hardware_parameters["pin_enable_" + std::to_string(i)]);
 47 |     auto pin_pos_ =
 48 |         stoi(info_.hardware_parameters["pin_pos_" + std::to_string(i)]);
 49 |     auto pin_neg_ =
 50 |         stoi(info_.hardware_parameters["pin_neg_" + std::to_string(i)]);
 51 |     motor_pin_sets_.emplace_back(std::make_tuple(pin_en_, pin_pos_, pin_neg_));
 52 |   }
 53 | 
 54 |   for (const hardware_interface::ComponentInfo &joint : info_.joints) {
 55 |     if (joint.command_interfaces.size() != 1) {
 56 |       RCLCPP_FATAL(rclcpp::get_logger("JetBotSystemHardware"),
 57 |                    "Joint '%s' has %zu command interfaces found. 1 expected.",
 58 |                    joint.name.c_str(), joint.command_interfaces.size());
 59 |       return hardware_interface::CallbackReturn::ERROR;
 60 |     }
 61 | 
 62 |     if (joint.command_interfaces[0].name !=
 63 |         hardware_interface::HW_IF_VELOCITY) {
 64 |       RCLCPP_FATAL(
 65 |           rclcpp::get_logger("JetBotSystemHardware"),
 66 |           "Joint '%s' have %s command interfaces found. '%s' expected.",
 67 |           joint.name.c_str(), joint.command_interfaces[0].name.c_str(),
 68 |           hardware_interface::HW_IF_VELOCITY);
 69 |       return hardware_interface::CallbackReturn::ERROR;
 70 |     }
 71 | 
 72 |     if (joint.state_interfaces.size() != 1) {
 73 |       RCLCPP_FATAL(rclcpp::get_logger("JetBotSystemHardware"),
 74 |                    "Joint '%s' has %zu state interfaces. 1 expected.",
 75 |                    joint.name.c_str(), joint.state_interfaces.size());
 76 |       return hardware_interface::CallbackReturn::ERROR;
 77 |     }
 78 | 
 79 |     if (joint.state_interfaces[0].name != hardware_interface::HW_IF_VELOCITY) {
 80 |       RCLCPP_FATAL(
 81 |           rclcpp::get_logger("JetBotSystemHardware"),
 82 |           "Joint '%s' have '%s' as only state interface. '%s' expected.",
 83 |           joint.name.c_str(), joint.state_interfaces[0].name.c_str(),
 84 |           hardware_interface::HW_IF_VELOCITY);
 85 |       return hardware_interface::CallbackReturn::ERROR;
 86 |     }
 87 |   }
 88 | 
 89 |   // Initialize I2C and Motors
 90 |   try {
 91 |     i2c_device_ = std::make_shared<I2CDevice>();
 92 |     for (auto i = 0u; i < info.joints.size(); i++) {
 93 |       motors_.emplace_back(i2c_device_, motor_pin_sets_[i],
 94 |                            info.joints[i].name);
 95 |     }
 96 |   } catch (std::exception &ex) {
 97 |     RCLCPP_FATAL(rclcpp::get_logger("JetBotSystemHardware"),
 98 |                  "Error while initializing I2C device or motors: '%s'",
 99 |                  ex.what());
100 |     return hardware_interface::CallbackReturn::ERROR;
101 |   }
102 | 
103 |   return hardware_interface::CallbackReturn::SUCCESS;
104 | }
105 | 
106 | std::vector<hardware_interface::StateInterface>
107 | JetBotSystemHardware::export_state_interfaces() {
108 |   std::vector<hardware_interface::StateInterface> state_interfaces;
109 |   for (auto i = 0u; i < info_.joints.size(); i++) {
110 |     state_interfaces.emplace_back(hardware_interface::StateInterface(
111 |         info_.joints[i].name, hardware_interface::HW_IF_VELOCITY,
112 |         &hw_velocities_[i]));
113 |   }
114 | 
115 |   return state_interfaces;
116 | }
117 | 
118 | std::vector<hardware_interface::CommandInterface>
119 | JetBotSystemHardware::export_command_interfaces() {
120 |   std::vector<hardware_interface::CommandInterface> command_interfaces;
121 |   for (auto i = 0u; i < info_.joints.size(); i++) {
122 |     command_interfaces.emplace_back(hardware_interface::CommandInterface(
123 |         info_.joints[i].name, hardware_interface::HW_IF_VELOCITY,
124 |         &hw_commands_[i]));
125 |   }
126 | 
127 |   return command_interfaces;
128 | }
129 | 
130 | hardware_interface::CallbackReturn JetBotSystemHardware::on_activate(
131 |     const rclcpp_lifecycle::State & /*previous_state*/) {
132 |   // set 0s as default values
133 |   for (auto i = 0u; i < hw_velocities_.size(); i++) {
134 |     if (std::isnan(hw_velocities_[i])) {
135 |       hw_velocities_[i] = 0;
136 |       hw_commands_[i] = 0;
137 |     }
138 |   }
139 | 
140 |   bool success = true;
141 |   for (auto motor : motors_) {
142 |     success = success && motor.trySetVelocity(0);
143 |   }
144 |   if (!success) {
145 |     RCLCPP_ERROR(rclcpp::get_logger("JetBotSystemHardware"),
146 |                  "Error setting velocity on motors while activating!");
147 |     return hardware_interface::CallbackReturn::ERROR;
148 |   }
149 | 
150 |   RCLCPP_INFO(rclcpp::get_logger("JetBotSystemHardware"),
151 |               "Successfully activated!");
152 |   return hardware_interface::CallbackReturn::SUCCESS;
153 | }
154 | 
155 | hardware_interface::CallbackReturn JetBotSystemHardware::on_deactivate(
156 |     const rclcpp_lifecycle::State & /*previous_state*/) {
157 |   bool success = true;
158 |   for (auto motor : motors_) {
159 |     success = success && motor.trySetVelocity(0);
160 |   }
161 |   if (!success) {
162 |     RCLCPP_ERROR(rclcpp::get_logger("JetBotSystemHardware"),
163 |                  "Error setting velocity on motors while deactivating!");
164 |     return hardware_interface::CallbackReturn::ERROR;
165 |   }
166 | 
167 |   RCLCPP_INFO(rclcpp::get_logger("JetBotSystemHardware"),
168 |               "Successfully deactivated!");
169 |   return hardware_interface::CallbackReturn::SUCCESS;
170 | }
171 | 
172 | hardware_interface::return_type JetBotSystemHardware::read(
173 |     const rclcpp::Time & /*time*/, const rclcpp::Duration & /*period*/) {
174 |   return hardware_interface::return_type::OK;
175 | }
176 | 
177 | hardware_interface::return_type JetBotSystemHardware::write(
178 |     const rclcpp::Time & /*time*/, const rclcpp::Duration & /*period*/) {
179 |   bool success = true;
180 |   for (auto i = 0u; i < hw_commands_.size(); i++) {
181 |     success = success && motors_[i].trySetVelocity(hw_commands_[i]);
182 |   }
183 |   if (!success) {
184 |     RCLCPP_ERROR(rclcpp::get_logger("JetBotSystemHardware"),
185 |                  "Error setting velocity on motors during write step!");
186 |     return hardware_interface::return_type::ERROR;
187 |   }
188 | 
189 |   return hardware_interface::return_type::OK;
190 | }
191 | 
192 | #include "pluginlib/class_list_macros.hpp"
193 | PLUGINLIB_EXPORT_CLASS(jetbot_control::JetBotSystemHardware,
194 |                        hardware_interface::SystemInterface)
195 | 


--------------------------------------------------------------------------------
/ROS2_CONTROL_LICENSE:
--------------------------------------------------------------------------------
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