ValueMotion to FlexMotion Conversion, Part II

This document provides information on converting your ValueMotion applications to the current FlexMotion API.

1. Applying High-Speed Capture
2. Performing Circular Vector Moves
3. Unleashing RTSI
4. Exploiting Buffered Operations

Applying High-Speed Capture

(High-Speed Capture available FlexMotion only)

Functions:

FlexMotion

Configure High-Speed Capture

Enable High-Speed Capture

Read Captured Position

Read High-Speed Capture

Quick Introduction:
High-Speed Capture allows you to capture the instantaneous encoder position when the associated high-speed capture input becomes active. You can use High-Speed Capture VIs to enable high-speed capture, read the status and the captured position, and set the polarity of the high-speed inputs.

The high-speed capture inputs can also function as latching general-purpose inputs. Configure as you would for high-speed capture operation, but ignore the captured position. You can then read the state of the latched inputs.

For more information consult your FlexMotion software reference manual.

Performing Circular Vector Moves

(Circular Interpolation available on FlexMotion 734x series controllers only)

Functions:

FlexMotion

Load Circular Arc

Load Spherical Arc

Load Helical Arc

Quick Introduction:
You can use Arc VIs to load parameters for circularly interpolated moves. It includes 2D circular arcs, 3D helical arcs, and full 3D spherical arcs VIs.

Circular interpolation is an advanced feature of FlexMotion and is primarily used in continuous path applications such as machining, pattern cutting, liquid dispensing, robotics, and so on.

Arc VIs are always sent to a vector space. Velocity and acceleration parameters loaded by executing those VIs on the vector space are used as the vector velocity and vector acceleration for all subsequent arc moves. All arc parameters are double-buffered and take effect upon the next Start Motion or Blend Motion VI execution.

For more information consult your FlexMotion software reference manual.

Unleashing RTSI

(RTSI available on FlexMotion only)

Functions:

FlexMotion

Select Signal

Read I/O Port

Set I/O Port Direction

Set I/O Port MOMO

Set I/O Port Polarity

Quick Introduction:
RTSI stands for Real-Time System Integration bus, a dedicated high-speed digital bus designed to facilitate system integration by low-level, high-speed, real-time communication between National Instruments boards. Using RTSI, motion boards can share high-speed digital signals with data acquisition, image acquisition, or digital I/O boards with no external cabling and without consuming bandwidth on the host bus. The RTSI bus also has built-in switching, so you can route signals to and from the bus on-the-fly through software.

For more information consult your FlexMotion software reference manual.

Exploiting Buffered Operations

(Buffered Operations available on FlexMotion 734x series controllers only)

Functions:

FlexMotion

Configure Buffer

Read Buffer

Write Buffer

Check Buffer

Clear Buffer

Quick Introduction:
Buffered operations allow you to create and manage memory buffers on your FlexMotion controller. You can create buffers that can hold thousands of points, read and write data to and from these buffers, and check the status of a buffer. Buffers can even be stored in ROM for later use.

One powerful use for buffers is Contouring. Contouring allows you to create any arbitrary motion profile. You specify an array of positions spaced apart in time by a specified interval, given in milliseconds. Those positions are then smoothly interpolated between using a cubic spline algorithm. Contouring is particularly useful when you want to create a motion profile that is not achievable with straight lines and arcs.

For more information consult your FlexMotion software reference manual.

Link to Part I

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