# ros2wd

**Repository Path**: stefantasy/ros2wd

## Basic Information

- **Project Name**: ros2wd
- **Description**: ROS差速控制板源码，arduino代码+上位机ROS代码 ，硬件是Arduino nano+ tb6612电机驱动+AB相编码器电机
- **Primary Language**: Python
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 2
- **Forks**: 1
- **Created**: 2021-04-16
- **Last Updated**: 2024-12-22

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

## Ros Arduino Bridge
--------
###  系统支持

* 在ros indigo，ros kinetic，ros melodic都可以正常使用

### 文件目录

- install_udev.sh  用来给usb设备 一键创建udev规则
- README_en.md 原版readme
- README .md  中文简易readme
- ros_arduino_bridge 空包
- ros_arduino_firmware 下位机arduino代码
- ros_arduino_msgs  消息和服务文件功能包
- ros_arduino_python 上位机功能包

## 功能

- 上位机通过读取下位机编码器数值计算发布odom历程消息话题 ，订阅cmd _vel话题，解析成串口数据发给下位机。 

- 可以通过服务控制arduino上的引脚的，输入输出，以及读取数字和模拟值

- 可以通过上位机控制底盘的舵机。

## 安装

- 确保安装了python-serial串口通信包

  $ sudo apt-get install python-serial

- 给下位机下载固件

通过arduino IDE给arduino下载固件。

- 创建usb设备udev规则

    - 插上arduino查看设备号

      $ lsusb

      Bus 001 Device 006: ID 1a86:7523 QinHeng Electronics HL-340 USB-Serial adapter

    - 创建一个 arduino.rules的文件，并编写udev规则如下

      KERNEL=="ttyUSB*", ATTRS{idVendor}=="1a86", ATTRS{idProduct}=="7523", MODE:="0666", GROUP:="dialout",  SYMLINK+="arduino"

    - 拷贝udev规则到对应目录

      $ sudo cp arduino.rules  /etc/udev/rules.d

    - 重启，使udev规则生效（笨办法）

    - 检查是否生效

      ls /dev/arduino

- 编译工作空间

  - 创建工作空间

    mkdir -p robot_ws/src

  - 进入src目录，拷贝代码到src目录

    cd ~/robot_ws/src

    git clone https://gitee.com/stefantasy/ros2wd.git

  - 编译工作空间

    cd ~/robot_ws/

    catkin_make

- 添加环境变量

  $ echo "source ~/robot_ws/devel/setup.bash" >>.bashrc

### 配置参数

- 修改ros2wd/ros_arduino_bridge/ros_arduino_python/config/my_arduino_params.yaml文件，检查下面的参数

- port: /dev/arduino   udev规则创建的别名
- baud: 57600 通信波特率和下位机代码的设置的保持一致
- timeout: 0.1 超时时间
- rate: 50 频率
- sensorstate_rate: 10
- use_base_controller: True 是否启动底盘
- base_controller_rate: 10 底盘控制频率
- base_frame: base_link 底盘tf坐标点
- wheel_diameter: 0.127 轮子的直径
- wheel_track: 0.284 轮距
- encoder_resolution: 1320  轮子一圈编码器数（4倍频）霍尔级数x减速比x4
- gear_reduction: 1.0 减速比
- motors_reversed: True 轮子转向是否反向
- Kp: 10  pid参数p
- Kd: 12
- Ki: 0
- Ko: 50
- accel_limit: 1.0 加速度限制

## 启动底盘

roslaunch ros_arduino_python arduino.launch


## 下位机串口控制指令列表

<pre>
#define ANALOG_READ    'a'
#define GET_BAUDRATE   'b'
#define PIN_MODE       'c'
#define DIGITAL_READ   'd'
#define READ_ENCODERS  'e'
#define MOTOR_SPEEDS   'm'
#define PING           'p'
#define RESET_ENCODERS 'r'
#define SERVO_WRITE    's'
#define SERVO_READ     't'
#define UPDATE_PID     'u'
#define DIGITAL_WRITE  'w'
#define ANALOG_WRITE   'x'
</pre>
下面的比较常用

例如 
- 发送e 获取左右轮的编码器数值，要确保轮子向前转动时，编码器数值增大，反之减小。

- 发送r，清零编码器数值。
- 发送 m 20 20，左右轮向前走20个编码器数值


## 查看传感器数值

To see the aggregated sensor data, echo the sensor state topic:

    $ rostopic echo /arduino/sensor_state

To see the data on any particular sensor, echo its topic name:

    $ rostopic echo /arduino/sensor/sensor_name

For example, if you have a sensor called ir\_front\_center, you can see
its data using:

    $ rostopic echo /arduino/sensor/ir_front_center

You can also graph the range data using rxplot:

    $ rxplot -p 60 /arduino/sensor/ir_front_center/range



ROS 服务
------------
The ros\_arduino\_python package also defines a few ROS services as follows:

**digital\_set\_direction** - set the direction of a digital pin

    $ rosservice call /arduino/digital_set_direction pin direction

where pin is the pin number and direction is 0 for input and 1 for output.

**digital\_write** - send a LOW (0) or HIGH (1) signal to a digital pin

    $ rosservice call /arduino/digital_write pin value

where pin is the pin number and value is 0 for LOW and 1 for HIGH.

**servo\_write** - set the position of a servo

    $ rosservice call /arduino/servo_write id pos

where id is the index of the servo as defined in the Arduino sketch (servos.h) and pos is the position in radians (0 - 3.14).

**servo\_read** - read the position of a servo

    $ rosservice call /arduino/servo_read id

where id is the index of the servo as defined in the Arduino sketch (servos.h)