some questions about configuration in MAX.

[leq_82]

Hi,Jochen

I'm sorry I have another question:How should I configure two axis so as they can run at different velocity in Two-Axis Vector Move in LabVIEW?Which VIs I should use?

[Jochen]

As you have stated, the encoder counts/rev setting should be 131072. You should be able to find the steps/rev value in your drive's manual. If not, please try to find out this value by moving the motor in open loop mode. First try to move the motor by exactly one revolution and note the number of steps that you have found. Then verify your result by moving the motor for e. g. 100 revolutions.
If there is a gearing box between your motor and your encoder you will have to take the gearing ratio into account, too.

In LabVIEW you can load the move constraints for multi axes moves in two ways.

1. Vector space moves. In this mode two or three axes are combined to a vector space. This is typically used in mechanical setups like xyz-stages. In this mode you need to load only the vector velocity and the vector acceleration.
   
   
2. If you want to move the axes independently, just load the move constraints for every axis seperately. Please refer to the shipping examples in LabVIEW (e. g. One-Axis Move (Accel - Max Velocity - Decel).vi).

Jochen

[leq_82]

Hi,Jochen

The current trajectory data couldn't updated when I use P-Command Mode.

you can refer to the attaced file.

[Jochen]

If you want to set inital values (accel., velocity) in MAX for your axes, click on the Move Constraints tab in the Trajectory Settings (3.jpg, bottom of the window).

2-D Interactive combines 2 axes into a vector space, so you can't set the move constraints for the axes seperately here (as described in my last post). Still you can set the vector accel. and velocity in the Main tab (14.jpg shows the Advanced tab).

Both, 1-D Interactive and 2-D Interactive overwrite the move constraints that you have set in the Trajectory Settings for the axes.

Jochen

[leq_82]

Thank you  answer my question.

But in Open-Loop Mode they work perfectly.It's make confused.

[leq_82]

Did you noticed  a strange phenomenon in 14.jpg?In current trajectory data the X axis position=Y Axis position=-32767,The vector following error=32767,and 32767 is the max value that following error can be set.

[Jochen]

Is there a chance that the A and B phases are switched? If you are sure that you have set the correct ratio for stepper steps/rev and encoder counts/rev please check, if the encoder input counts into the correct direction. If not, please change the polarity for one phase (e. g. phase B) to Active Low Polarity.



This might be a bit pragramatic but on the other hand, why do you care? If open loop mode works fine for you, just use it.

Jochen

Message Edited by Jochen on 07-13-2007 08:46 AM

[leq_82]

Hi,Jochen

For the velocity profile,how can I compute the acceleration,deceleration,acceleration time,deceleration time?

Which value is appropriate?Have any formula can compute these value?

Thanks

EnquanLi

[Jochen]

EnquanLi,

I'm sorry but I don't understand exactly what you are looking for.
You should set accel/decel values according to the needs of your application. There are no complicated formulas here. E. g. if you set an acceleration value of 10,000 steps/s^2 the axis will accelerate to a velocity of 100,000 steps/sec within 10 seconds. Higher acceleration and deceleration values result in higher torque and higher current, but of course these values are limited by the specs of your drive.

I hope this helps,

Jochen

[leq_82]

Hi,Jochen

I have a stepper motor,it's type is KP4AM2-008,because this motor is too old,I can't find its data sheet.

Its a two phase hybrid stepper motor,I don't know its rated current and rated voltage.its drive is PBD 3517/1 .

When I connect the UMI7764,drive and motor then I use MAX to debug the motor.when I set the velocity to

100RPM,It works normally.But after I change the velocity from 100RPM to 200RPM,it's behavior become very

strange.it can't run smothly.It run a moment then stop a while then go on running,and stop a while again...,

It continually repeat these action.If I give the velocity faster,e.g 500RPM,the shaft don't rotate but I can fell

the motor's inside run at a high speed when my hand touch it.I don't know why?I think it's the acceleration

is not proper.May I am incorrect.

Looking forward to your help!Thanks again!

EnquanLi

China