utbots_manipulation

This stack contains packages related to manipulators, such as:

• 3R_Manipulator_Firmware
• Heracles_Firmware
• manipulator_controller_cpp

Getting started

Installation

cd catkin_ws/src
git clone https://github.com/UtBot-UTFPR/custom_msg
git clone --recurse-submodules https://github.com/UtBotsAtHome-UTFPR/utbots_manipulation.git

Building

cd ..
catkin_make

Running

See the usage explanation accessing each package in the repository or the overview below

Overview

manipulator_controller_cpp

ROS nodes:

• xz_controller_node
• Receives: Point() - goal point
• Publishes: set_angles() - arm angles that reach the input point (in plane XZ)
• xy_controller_node
• Receives: Point() - goal point
• Publishes: Twist() - velocity command that makes robot turn (in plane XY)
• setpoint_publisher_node
• Publishes: Point() - can define a new point by pressing space

Arm joints

OMB: ombro
COT: cotovelo
PUN: punho
GAR: garra

Parameters (config/parameters.yaml)

• Set arm lengths
• Set angular corrections
• Set acceptable yaw error (for XY twist)
• Set Kp constant used in PID (for XY twist)
• Set whether or not display debug info ```

Launch files

roslaunch manipulator_controller_cpp setpoint_xy.launch # only xy
roslaunch manipulator_controller_cpp setpoint_xz.launch # only xz
roslaunch manipulator_controller_cpp setpoint_xyz.launch # combines xy and xz

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3R_Manipulator_Firmware

• Pre-requisite: download and install Arduino IDE

• Pre-requisite: custom headers compilation

Since we have ROS custom messages defining new types of ROS messages, we need to compile them specifically for the Arduinos

# Compile catkin_ws
cd ~/catkin_ws
catkin_make
# Install rosserial_arduino
sudo apt install ros-noetic-rosserial-arduino
# Create libraries folder
mkdir -p ~/Arduino/libraries
cd ~/Arduino/libraries
# Run make_libraries in the current folder
# Make sure you have sourced ~/catkin_ws/devel/setup.bash
rosrun rosserial_arduino make_libraries.py .

Compilation (with Arduino IDE)

• Open Arduino IDE
• File > Open... > ???/utbots_manipulation/3R_Manipulator_Firmware/Point/???/file.ino
• Select board (Mega 2560)
• Click Verify to check code problems
• Plug Arduino to PC and upload the firmware to it

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Using rosserial_python to interface ROS and Arduino

1. Find out the name of the port used by the Arduino in the PC
2. Connect board to PC via USB
3. Go to /dev/serial/by-id and find out the ID of your device

• This file is actually a symlink to the PORT NAME
• If you run ls -la /dev/serial/by-id/YOUR_ID, you will find out that it points to a file called /dev/SOMETHING. This is the PORT NAME
• PORT NAME may vary if you plug multiple devices or reset the PC
• PORT ID is static
• Therefore, you should use PORT ID whenever you can

Run rosserial_python

# Install rosserial_python
sudo apt install ros-noetic-rosserial-python
rosrun rosserial_python serial_node.py _port:=/dev/PORT_NAME_OR_ID _baud:=57600

WARNING Serial communication is exclusive. This means you won't be able to simultaneously run rosserial, upload new firmware or monitor serial

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Heracles_Firmware