Using EtherCAT Motion Drives with NI Real-Time Controllers


What is NI SoftMotion and SoftMotion Drive Interface?

The LabVIEW SoftMotion Module enhances LabVIEW by adding the capabilities to control motors and drives using high-level commands and develop custom motion applications using NI real-time and FPGA. With NI SoftMotion, you can use a LabVIEW project to configure all of your motion axis settings, test your configuration, tune your motors, and quickly integrate custom motion control into your application.  By pairing NI SoftMotion with a real-time operating system and FPGA on NI embedded controllers like PXI RT, Industrial Controller, and CompactRIO, you can easily synchronize multiple motion axes with I/O, Vision, HMI, and other functions.

The SoftMotion Drive Interface (SDI) is the solution National Instruments developed to standardize communication with third-party EtherCAT motor drives.  Conventional communication with an EtherCAT-capable motor drive is done by reading and writing commands to PDO and SDO memory registers on a drive.  The SDI takes care of this low-level communication to PDO and SDO registers for you, and allows you to focus on the high-level control aspects of your application using the SoftMotion API. SDI Plug-ins contain all the necessary components to add the EtherCAT drive to your LabVIEW Project and control the drive using SoftMotion.

Download SDI Plug-ins

You can download SDI Plug-ins from the NI Tools Network. The SDI framework was introduced with SoftMotion 2014 SP1 and newer, although some plug-ins require later versions of LabVIEW and SoftMotion.  Plug-ins install as VI Packages through the VI Package Manager.  SDI Plug-ins are hosted on the LabVIEW Tools Network, and the currently supported list of NI's Drive Partners is below.

Who is an NI Drive Partner?

Vendor Name Vendor Drive Model SDI Plug-in Link Minimum Software Set Version
Bosch-Rexroth IndraDrive
Cs, C, M, Mi, ML
Install 2016
Copley Controls Accelnet Plus
Stepnet Plus
Xenus Plus
Xenus Plus Compact
Install 2016
Delta Products Corporation ASDA-A2 Install 2016
Dunkermotoren GmbH BG EC Install 2016
Elmo Motion Control Gold EtherCAT Install 2016
Jenaer Antriebstechnik GmbH ECOVARIO Contact Supplier 2015
Kollmorgen EtherCAT AKD Natively Supported 2010
maxon motor MAXPOS Install 2016
Mitsubishi Electric MR-J4-TM Install 2016
Panasonic MINAS A5B Install 2016
Parker Motion P Series Install 2016
E Series Install 2016
Compax3 Install 2016
Schneider Electric Lexium 32M
Lexium 32i
Install 2016
Yaskawa Sigma-7 100/200V Install 2016

Note: VI Package Manager must be installed to install plug-ins. The Minimum Software Set Version applies to LabVIEW and the LabVIEW SoftMotion Module. For full compatibility notes, see the related link below.

SoftMotion Drive Interface Overview

Traditionally, integrating a third-party EtherCAT motor drive into control software is a process of learning the correct PDO/SDO data registers, the data requirements for these registers, and when to communicate with them from code.  Despite most EtherCAT-capable drives conforming to the CiA 402 standard, many operational behaviors differ between drive vendor implementations of CiA 402.  These differences have presented a challenge to integrators that have expressed time and again, the need for a unified interface to reduce development time and cost.

National Instruments provides a unified command framework called the SoftMotion Drive Interface as a solution to this issue.  The SoftMotion Drive Interface (SDI) enables you to easily work with third-party EtherCAT motor drives in SoftMotion by installing Plug-ins for third-party drives.  These Plug-ins are built to translate high-level move and configuration commands into the necessary communication to a third-party drive.  Instead of learning which PDO a user needs to send a command to, the user can simply send a command using the hardware-agnostic functions provided by the NI SoftMotion Module in LabVIEW.

Since the functions provided by NI SoftMotion are hardware-agnostic, the same LabVIEW control code can be re-used with a variety of different hardware with little to no change to the code.  Integrators can use the SoftMotion Drive Interface as a method for developing code that can work with any hardware for which a SDI Plug-in is available.

What Hardware is Required to use SDI?

The table above lists the EtherCAT motor drives compatible with SDI. Only the single-axis variant of each drive is supported.

SDI also requires the use of a controller that supports EtherCAT and LabVIEW Real-Time. This includes CompactRIO, CompactDAQ, PXI, and Industrial Controllers with LabVIEW Real-Time. For a more comprehensive list, refer to SoftMotion Compatibility with LabVIEW Real-Time Controllers.