This document contains installation and programming considerations, system requirements, licensing information, a list of changes in this version of NI Motion Assistant, and a list of NI Motion Assistant known issues.
Installation and Upgrade Information
NI Motion Assistant 2.3 Changes and Enhancements
NI Motion Assistant 2.3 General Considerations
NI Motion Assistant 2.3 Known Issues
Previous NI Motion Assistant Changes and Enhancements
National Instruments Motion Assistant is a stand-alone prototyping tool for quickly developing motion applications. NI Motion Assistant allows you to graphically construct and preview motion applications without writing any code. When you have completed a prototype in NI Motion Assistant, you can generate LabVIEW or C code for further application development using NI-Motion. You also can generate code recipes for coding the application in a text-based language, such as Microsoft Visual Basic.
NI Motion Assistant includes the following features:
Note: If you already have a registered version of NI Motion Assistant 1.3 or earlier, you can purchase an upgrade to NI Motion Assistant 2.3 using National Instruments part number 850553C-01. Registered NI Motion Assistant 2.x users can upgrade to NI Motion Assistant 2.3 for free.
You must install the NI-Motion driver software before installing NI Motion Assistant. To install NI Motion Assistant, insert the NI Motion Assistant CD into the CD-ROM drive. The NI Motion Assistant installation screen launches automatically. Select the appropriate option depending on whether you want to install NI Motion Assistant, review the release notes, or exit the installation program.
Visit ni.com/motion for NI Motion Assistant updates.
At the end of the NI Motion Assistant installation process, a licensing wizard appears. Follow the onscreen instructions to activate the license for NI Motion Assistant.
Refer to the Activating Your Software topic in the NI Motion Assistant Help for detailed information about activation.
Note You are required to activate the license for NI Motion Assistant even if you previously had a licensed version.
NI Motion Assistant is compatible with NI-Motion 7.0 and later. To create LabVIEW code from an NI Motion Assistant prototype, you must have LabVIEW 7.1 or later installed. NI Motion Assistant requires that either the actual controller or the virtual representation of one of the following motion controllers be installed in the computer:
If you do not have one of the listed motion controllers, you can use a virtual motion controller in Measurement & Automation Explorer (MAX) to preview the functionality of NI Motion Assistant. Follow the instructions in the NI Motion Assistant Help to install a virtual motion controller. You must have NI-Motion 7.0 or later installed to use a virtual motion controller.
NI Motion Assistant 2.3 is fully supported on LabVIEW 8.6.
The NI SoftMotion Controller is not supported on NI Motion Assistant 2.3. NI Motion Assistant 2.2 was the last version with support for the NI SoftMotion Controller.
Previous versions of NI Motion Assistant displayed an error message with an incorrect solution in cases when NI Motion Assistant could not calculate the move profile using the supplied move constraint and target position combinations. NI Motion Assistant now displays the following updated error text:
"The move cannot be calculated with the provided move constraint and target position values. To correct this situation, decrease the velocity and/or decrease the acceleration and/or increase the size of the move."
It is no longer possible to set the initial velocity using the Set Move Properties VI, the NIMASetMoveParams C function, or using the VelocitySpecificationInput property in Visual Basic, to a negative value for arc, contour, or straight-line moves configured for position mode. In addition, final velocity must be set to zero for arc, contour, and straight-line moves in position mode. Setting any other values for initial or final velocity for arc and contour moves returns NIMA_invalidMoveConstraint error. Setting a non-zero positive value for final velocity for a straight-line move in position mode does not return an error. Instead, the value is coerced to zero. Refer to the following table for a summary of the new behavior.
| Move Type | Velocity Value | Result |
|---|---|---|
| Arc Move | Initial Velocity: Negative OR Final Velocity: Non-zero |
NIMA_invalidMoveConstraint error |
| Contour Move | Initial Velocity: Negative OR Final Velocity: Non-zero |
NIMA_invalidMoveConstraint error |
| Straight-Line Move (Position Mode) | Initial Velocity: Negative OR Final Velocity: Negative |
NIMA_invalidMoveConstraint error |
| Final Velocity: Non-zero Positive | No error, velocity is coerced to zero. | |
| Straight-Line Move (Velocity Mode) | Initial Velocity: Any Value OR Final Velocity: Any Value |
No error |
NI Motion Assistant loads jerk values in units/s3. When LabVIEW or C code is generated, the jerk value is converted to time in update sample periods. However, at certain velocities, the jerk value for CAD moves was not converted and was instead inserted directly into the generated LabVIEW and C code. This conversion problem is fixed in NI Motion Assistant 2.3.
Previous versions of NI Motion Assistant incorrectly displayed the acceleration at very high speeds. This has been corrected in NI Motion Assistant 2.3.
Position profiles calculated using the NI Motion Assistant API previously appended additional zeroes to the beginning of the profile. These leading zeroes are now removed.
You cannot generate LabVIEW code from an NI Motion Assistant script for a real-time target. Refer to the LabVIEW Real-Time Module Considerations section of How do I create code from a motion script? in the NI Motion Assistant Help for detailed instructions about creating code for RT targets.
The following additional considerations apply to CAD moves:
NI Motion Assistant uses a technique called smart contouring to smoothly move through the positions you specify. Refer to the Contoured Move glossary topic of the NI Motion Assistant Help for smart contouring guidelines you must follow to avoid unexpected behavior.
The controller starts from the current position of the axes and travels to the end of the first move. To ensure that the actual system and the position profile you specify match, you must always begin an NI Motion Assistant script with a Reference Move. Refer to Reference Move in the Motion Step Help book of the NI Motion Assistant Help for detailed instructions about adding and configuring a Reference Move Step.
Because of the way the 64-bit version of Microsoft Windows Vista executes CHM files, links from the CHM file to launch the MAX application do not work if the CHM file is opened from the Start menu or directly from the <Motion Assistant>\Help\ folder. These links work correctly when the CHM file is opened from inside the NI Motion Assistant or NI LabVIEW environment.
If you make changes to a file referenced in an NI Motion Assistant script, such as buffered breakpoint positions, contour points, or CAD files, you must reload the file for these changes to take effect.
The path to the tab delimited text files on the Contouring Parameters tab in the NI Motion Assistant script examples installed at <Motion Assistant>\Examples\ is an absolute path to <Program Files>\National Instruments\Motion Assistant\Examples. If you have installed NI Motion Assistant to a custom install location or are using a localized operating system these examples do not work until you manually browse to the correct location of the text file, which is \Motion Assistant\Examples\Contouring\ by default.
Unlike other move types, Reference Moves cannot be performed on coordinates, so the vector move constraints must be converted to per-axis values for 2D and 3D moves to function correctly. NI Motion Assistant does not convert the acceleration and deceleration values to component values in the generated code, so these values must be calculated and updated in the generated code after code generation is complete.
When you generate LabVIEW code from NI Motion Assistant, the Save VI dialog box from LabVIEW opens so you can save your generated VI. However, if LabVIEW is already open, the dialog box opens behind the active NI Motion Assistant window, making it appear that the code generation is frozen. In this case you must manually switch to LabVIEW to make the Save VI dialog box active and complete the code generation process.
Refer to KnowledgeBase article 47EKNFFL, NI Motion Assistant Release Notes, at ni.com/kb for access to previous NI Motion Assistant release notes, starting with NI Motion Assistant 1.3.
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