6 change speed on the fly, Change speed on the fly – ADLINK PCI-8134A User Manual

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60

Operations

are numbered either from left to right or right to left on the PCI slots. These
card numbers will affect the corresponding axis number on the cards. And
the axis number is the first argument for most functions called in the library.
So it is important to identify the axis number before writing application
programs. For example, if 3 PCI-8134/PCI-8134A cards are plugged in the
PCI slots. Then the corresponding axis number on each card will be:

Axis No.
Card No.

Axis 1

Axis 2

Axis 3

Axis 4

1

0

1

2

3

2

4

5

6

7

3

8

9

10

11

If we want to accelerate Axis 3 of Card2 from 0 to 10000pps in 0.5sec for
Constant Velocity Mode operation. The axis number should be 6. The code
on the program will be:

v_move(6, 0, 10000, 0.5);

To determine the right card number, Try and Error may be necessary before
application. Motion Creator can be utilized to minimize the search time.

The newest DLL supports the combination of both PCI-8134 and PCI-
8134A in one system.

4.6

Change Speed on the Fly

You can change the velocity profile of command pulse ouput during
operation by v_change() function. This function changes the maximum
velocity setting during operation. However, if you operate under “Preset
Mode” (like start_a_move(),…), you are not allowed to change the
acceleration parameter during operation because the deceleration point is
pre-determined. But changing the acceleration parameter when operating
under “Constant Velocity Mode” is valid. Changing speed pattern on the fly
is valid no matter what you choose “Trapezoidal Velocity Profile” or “S-curve
Velocity Profile”. Here we use an example of Trapezoidal velocity profile to
illustarte this function.

Example: There are 3 speed change sensor during an absolute move for
200000 pulses. Initial maximum speed is 10000pps. Change to 25000pps if

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