How to control Maxon MCD Epos with ROS_canopen and IXXAT adapter

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Important Edit: for ROS CANopen you don't need to load the controllers, only the URDF file of the motor to get the joints and specifications of it.

Hi all, I am trying to build an RHex style robot.

For it locomotion I have selected 6 Maxon MCD Epos motors. That are connected via CAN with an IXXAT USB-to-CAN adapter.

First of all, I try to manage the MCD with the package epos_hardware ( link ), I get all the motors work but with a different configuration (the first one via USB-RS232 to the computer and then it generates a CAN network with the others motors). The problem is that the frequency to control the motors is only 3 Hz and I need at least 20 Hz.

So, having try ros package epos_hardware and testing that it can't connect to Maxon motors via Canopen I am trying to use ros_canopen package ( can_open ) and following the instructions from Mathias (Instructions)

But I'm having the same errors that CJ.

[ INFO] [1527765873.067864309]: Initializing XXX
[ INFO] [1527765873.068224620]: Current state: 1 device error: system:0 internal_error: 0 (OK)
[ INFO] [1527765873.068457195]: Current state: 2 device error: system:0 internal_error: 0 (OK)
[ INFO] [1527765881.288870355]: Current state: 2 device error: system:125 internal_error: 0 (OK)
[ INFO] [1527765881.288943915]: Current state: 0 device error: system:125 internal_error: 0 (OK)
[ INFO] [1527765881.288998158]: Current state: 0 device error: system:0 internal_error: 0 (OK)
[ INFO] [1527765881.289078940]: Current state: 0 device error: system:0 internal_error: 0 (OK)

And also, some errors with the controllers

[INFO] [1527765775.163013]: Controller Spawner: Waiting for service controller_manager/load_controller
[WARN] [1527765805.295161]: Controller Spawner couldn't find the expected controller_manager ROS interface.

I follow all the steps that Mathias explain in the other question.

1. Setup SocketCAN

2. Prepare URDF with sane limits The xacro file of the robot is correct. You can download it from here

3. Prepare EDS/DCF, take special care for the PDO mapping I generated all the 6 files with Maxon Epos Studio and change PDOmapping=0 to PDOmapping=1

4. Prepare driver config

   • prepare chain config
   • configure motor-specific settings, especially unit conversions This is my yaml file with the configuration (canopen.yaml)

bus:

  device: can0
  loopback: false
  driver_plugin: can::SocketCANInterface
  master_allocator: canopen::SimpleMaster::Allocator
sync:
  interval_ms: 10
  update_ms: <interval_ms>
  overflow: 0
  #heartbeat: # simple heartbeat producer, optional!
  #rate: 20 # heartbeat rate
  msg: "77f#05" # message to send, cansend format: heartbeat of node 127 with status 5=Started

nodes:

node1:
    id: 1
    eds_pkg: canopen_chain_node # optionals package name for relative path
    eds_file: "config/MCDepos_node_1.dcf" # path to EDS/DCF file

  node2:
    id: 2
    eds_pkg: canopen_chain_node # optionals package name for relative path
    eds_file: "config/MCDepos_node_2.dcf" # path to EDS/DCF file

  node3:
    id: 3
    eds_pkg: canopen_chain_node # optionals package name for relative path
    eds_file: "config/MCDepos_node_3.dcf" # path to EDS/DCF file

  node4:
    id: 4
    eds_pkg: canopen_chain_node # optionals package name for relative path
    eds_file: "config/MCDepos_node_4.dcf" # path to EDS/DCF file

  node5:
    id: 5
    eds_pkg: canopen_chain_node # optionals package name for relative path
    eds_file: "config ...