Trinamic Stepper Motor control

Introduction

This tutorial is a simple example of how to use the ros2_canopen package to control a Trinamic smart stepper motor.

Getting started

If you haven’t already done so, follow the steps in the Configuration Package.

Configuration

• Create a new folder in the config folder of your configuration package. Name it single-pd42.

• Download .eds file from Trinamic and place TMCM-1270.eds in the single-pd42 folder.

• Create a bus.yml file in the single-pd42 folder with the following content:

  options:
      dcf_path: "@BUS_CONFIG_PATH@"
  
  master:
      node_id: 2
      driver: "ros2_canopen::MasterDriver"
      package: "canopen_master_driver"
      sync_period: 20000
  
  
  defaults:
      dcf: "TMCM-1270.eds"
      driver: "ros2_canopen::Cia402Driver"
      package: "canopen_402_driver"
      polling: false
      heartbeat_producer: 1000 # Heartbeat every 1000 ms
      sdo: # SDO executed during config
          - {index: 0x6081, sub_index: 0, value: 500000} # Set velocity
          - {index: 0x6083, sub_index: 0, value: 1000000} # Set acceleration
          - {index: 0x6083, sub_index: 0, value: 1000000} # Set deceleration
          - {index: 0x6085, sub_index: 0, value: 1000000} # Set quickstop deceleration
          - {index: 0x6098, sub_index: 0, value: 35} # Set default homing mode to 35
          - {index: 0x60C2, sub_index: 1, value: 50} # Set interpolation time for cyclic modes to 50 ms
          - {index: 0x60C2, sub_index: 2, value: -3} # Set base 10-3s
  
  nodes:
      trinamic_pd42:
          node_id: 1
  

• Edit the CMakeLists.txt file in the config folder of your configuration package and add the following lines:

  cmake_minimum_required(VERSION 3.8)
  project(trinamic_pd42_can)
  
  if(CMAKE_COMPILER_IS_GNUCXX OR CMAKE_CXX_COMPILER_ID MATCHES "Clang")
  add_compile_options(-Wall -Wextra -Wpedantic)
  endif()
  
  # find dependencies
  find_package(ament_cmake REQUIRED)
  find_package(rclcpp REQUIRED)
  find_package(std_srvs REQUIRED)
  find_package(canopen REQUIRED)
  find_package(lely_core_libraries REQUIRED)
  find_package(canopen_interfaces REQUIRED)
  
  # generate_dcf(single-pd42)
  cogen_dcf(single-pd42)
  
  add_executable(position_tick_client src/position_tick_motor.cpp)
  ament_target_dependencies(position_tick_client
  rclcpp std_srvs canopen_interfaces)
  
  
  install(TARGETS
  position_tick_client
  DESTINATION lib/${PROJECT_NAME})
  
  # install launch file
  install(DIRECTORY
  launch/
  DESTINATION share/${PROJECT_NAME}
  )
  
  if(BUILD_TESTING)
  find_package(ament_lint_auto REQUIRED)
  endif()
  
  ament_package()
  

• Create launch file in folder launch and add the following content:

  import os
  import sys
  
  import launch
  from launch.actions import IncludeLaunchDescription
  from launch.launch_description_sources import PythonLaunchDescriptionSource
  from ament_index_python import get_package_share_directory
  from launch import LaunchDescription
  
  
  def generate_launch_description():
      ld = LaunchDescription()
      slave_eds_path = os.path.join(
          get_package_share_directory("trinamic_pd42_can"), "config", "single-pd42", "TMCM-1270.eds"
      )
  
      slave_node_1 = IncludeLaunchDescription(
          PythonLaunchDescriptionSource(
              [
                  os.path.join(get_package_share_directory("canopen_fake_slaves"), "launch"),
                  "/cia402_slave.launch.py",
              ]
          ),
          launch_arguments={
              "node_id": "1",
              "node_name": "pd42_slave",
              "slave_config": slave_eds_path,
          }.items(),
      )
      master_bin_path = os.path.join(
          get_package_share_directory("trinamic_pd42_can"),
          "config",
          "single-pd42",
          "master.bin",
      )
      if not os.path.exists(master_bin_path):
          master_bin_path = ""
  
      device_container = IncludeLaunchDescription(
          PythonLaunchDescriptionSource(
              [
                  os.path.join(get_package_share_directory("canopen_core"), "launch"),
                  "/canopen.launch.py",
              ]
          ),
          launch_arguments={
              "master_config": os.path.join(
                  get_package_share_directory("trinamic_pd42_can"),
                  "config",
                  "single-pd42",
                  "master.dcf",
              ),
              "master_bin": master_bin_path,
              "bus_config": os.path.join(
                  get_package_share_directory("trinamic_pd42_can"),
                  "config",
                  "single-pd42",
                  "bus.yml",
              ),
              "can_interface_name": "vcan0",
          }.items(),
      )
  
      ld.add_action(device_container)
      ld.add_action(slave_node_1)
  
      return ld
  

Running the example

To begin, follow the instructions for Setup CAN Controller, which can be done using either a virtual or peak CAN interface.

If you prefer to use a real CAN interface, you will need to modify the launch file by changing the can_interface_name argument to can0. Additionally, if you are using real hardware, you should comment out the fake slave launch by adding a # in front of the line ld.add_action(slave_node_1). Once these changes have been made, you can launch the example.

ros2 launch trinamic_pd42_can <your launch file>.launch.py

Initilaize the motor by calling the service /trinamic_pd42/init:

ros2 service call /trinamic_pd42/init std_srvs/srv/Trigger

Set the operation mode to Profile Position Mode by calling the service /trinamic_pd42/position_mode:

ros2 service call /trinamic_pd42/position_mode std_srvs/srv/Trigger

Set the target to the motor by calling the service /trinamic_pd42/target:

ros2 service call /trinamic_pd42/target canopen_interfaces/srv/COTargetDouble "{ target: 10.0 }"

Reference

You can find the source code for this example in the trinamic_pd42_can package.