WorldViz User Forum - How to get real time position of a object which is connected to a haptic device

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How to get real time position of a object which is connected to a haptic device

How to get real time position of a object which is connected to a haptic device?

My haptic device is phantom omni

I tried to print it out, it shows [0,0,0] all the time.

I need to read the real time position and then apply different functions based on different positions.

Do you get changing positions with the following code?

Code:

import viz

import vizact

viz.go()



sensable = viz.add('sensable.dle')

device = sensable.addHapticDevice()



def printPosition():

        print device.getPosition()

        

vizact.ontimer(0,printPosition)

Thanks Jeff.

May I ask how can I get the real-time spring force I applied?
I tried .getMagnitude(). But what I get is a constant I set in addSpringEffect.

.addSpringEffect( gain=None
,magnitude=None
,position=None
,referenceFrame=None )
Position here represents the effect position, right?

And what is the relationship between magnitude and spring force? In F = k(P-X), magnitude is the max spring force?

Quote:

May I ask how can I get the real-time spring force I applied?

After you've defined and enabled the spring effect you could create your own function that returns the spring effect force based on F = k(P - X). Something like the following:

Code:

import vizmat



def getSpringForce():



        #get effect position and gain.

        P = springEffect.getPosition()

        k = springEffect.getGain()

        

        #get haptic device position

        X = device.getPosition()

        

        #return force

        return k * vizmat.Distance(P,X)

Quote:

Position here represents the effect position, right?

Yes, the position value you pass in when you define the spring effect is the effect position.

Quote:

And what is the relationship between magnitude and spring force? In F = k(P-X), magnitude is the max spring force?

The magnitude of the effect force is capped at the magnitude value you define.

Thank you so much!!!