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farrokh747
09-07-2008, 07:06 AM
Hi All -

Has anyone tried to use the 4 Motor Servo Controller with the Scorpion XL DC Motor Controller? I've been testing this for the 747 autothrottle and it works, but the motor movement takes place only in one direction.

Flow: PC > PHIDGETS 4 MOTOR SERVO CARD > SCORPIONXL > DC MOTOR
RUNNING FS2PHIDGETS -
Servo channel assigned to Eng 1 Throttle Lever

The changes in FS (auto)throttle lever position indicates clearly in the FS2Phidgets software values, but the movement of the DC Motor is in the same (clock) direction even if the values are decreasing (retard)

BTW, I'm using a DC motor (instead of the HITEC servos due to the load of the original TQ)

Also, Alan, is there a setting somewhere to eleminate lever movement for small inc/dec in FS values?

Cheers, and thanks in advance!

FC

CocnutAir
09-08-2008, 03:26 AM
Farrokh,

Can't say that I have. Did not think it was even possible.

Which Hitec servos were you using - the hi-torque 805BB's ?

Are you using the Advanced Servo phidget?

I am inclined towards Stepper Motors for auto-throttles.

There are a number of new cards and features I would like to play around with, but that is beyond my current budget to buy a nearly complete set of cards every few months.

Regards,
Alan.

farrokh747
09-08-2008, 02:11 PM
HI Alan -

It works well actually - the only hitch is that the Scorpion card turns the motor in one direction only regardless of the movement direction of the "virtual" throttle levers -

I did some tests with the Hitec 805BB and as we know, the arm swings both ways, and follows the AT perfectly - alas, I cannot use this since they're just not powerful enough - hence the thought to use a DC motor -

Some time ago, I spoke to the folks at Phidgets and they recommended the ScorpionXL DC motor controller - it's rigged up as seen on the top of this page:

http://www.trossenrobotics.com/store/c/2666-DC-Motor-Controllers.aspx

also, they've posted this tutorial on youtube -

http://www.youtube.com/watch?v=X4stWDy-bPA

I'll call them again and se if there's some jumper setting on the XL board - or something...

""Are you using the Advanced Servo phidget?""

I'm afraid I don't know what this is - I'm using V4.5 right now - is this a function on a later build?

Thanks for the reply - !

FC

CocnutAir
09-09-2008, 01:46 PM
Farrokh,

Those PWM motor controllers should be reversible.
They ship standard in mixed mode.
Might want to change jumpers to be in "tank" mode.
i.e. each motor contolled independantly.
To do this - both the M and T jumpers must be set to ON.
Give that a whirl.

Regards,
Alan.

farrokh747
09-09-2008, 05:04 PM
Hi Alan -

"To do this - both the M and T jumpers must be set to ON."

I did exactly this - the jumpers are in the right place - M & T are ON -

Will do some more tests and report -

Will also try and get thru to the scorpion people - they seem to be on holiday right now -

If this works, it will solve some important issues using DC motors for any servo apps -

As far I can see, the phidgets end of things seems to be OK - there may be something connected to calibration of the Scorpion card - will investigate

fc

Upgraded to V 4.3.7 ...!