How Much Torque Needed for Stepper Motor?

erk1313

Hello,

I bought·a 9V unipolar stepper motor with a torque of 800gm-cm (.5A current).· Compared to other motors on Jameco, it seemed like a lot of torque.· I'm trying to power a small toy car (~5lbs) and the motor is worthless...· I can stop it by lightly pressing against the wheel--it just doesn't put out hardly any torque.

----Can anyone give me advice on how much torque (g-cm) is needed to power a small toy car?

Thank you so much for your help.· Here is the link to the motor I bought
http://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&storeId=10001&catalogId=10001&productId=130538


Eric

Bean

Steppers have most torque at slow speed. and using two poles at the same time.

How fast are you stepping it ?

Are you using two poles at the same time ?

Can you post the code ?

Bean.

caper

' {$STAMP BS1}DIRS = %00011111SYMBOL Delay = B0SYMBOL Up = B1SYMBOL i = B4Delay = 10STEP1:PAUSE 10000UP = PIN5IF UP = 1 THEN PointUp GOTO PointDown PointUp: IF PIN6=1 OR PIN7=1 THEN Align PINS=%00001010 PAUSE Delay IF PIN6=1 OR PIN7=1 THEN Align PINS=%00001100 PAUSE Delay IF PIN6=1 OR PIN7=1 THEN Align PINS=%00000101 PAUSE Delay IF PIN6=1 OR PIN7=1 THEN Align PINS=%00000011 PAUSE Delay GOTO PointUp PointDown: IF PIN6=1 OR PIN7=1 THEN Align PINS=%00001010 PAUSE Delay IF PIN6=1 OR PIN7=1 THEN Align PINS=%00000011 PAUSE Delay IF PIN6=1 OR PIN7=1 THEN Align PINS=%00000101 PAUSE Delay IF PIN6=1 OR PIN7=1 THEN Align PINS=%00001100 PAUSE Delay GOTO PointDownAlign: IF PIN6=1 THEN BrakeLeft IF PIN7=1 THEN BrakeRightENDBrakeLeft: IF up=1 THEN BrakeLeftUp GOTO BrakeLeftDown BrakeLeftUp: IF PIN7=1 THEN TurnAround PINS=%00001010 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001110 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00000110 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00000010 PAUSE Delay GOTO BrakeLeftUp BrakeLeftDown: IF PIN7=1 THEN TurnAround PINS=%00001010 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00000010 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00000110 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001110 PAUSE Delay GOTO BrakeLeftUpBrakeRight: GOTO BrakeRightDown BrakeRightUp: IF PIN7=1 THEN TurnAround PINS=%00001010 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001000 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001001 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001011 PAUSE Delay GOTO BrakeRightUp BrakeRightDown: IF PIN7=1 THEN TurnAround PINS=%00001010 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001011 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001001 PAUSE Delay IF PIN7=1 THEN TurnAround PINS=%00001000 PAUSE Delay GOTO BrakeRightDownTurnAround: FOR i = 1 TO 100 PINS=%00001010 PAUSE Delay PINS=%00001111 PAUSE Delay PINS=%00000101 PAUSE Delay PINS=%00000000 PAUSE Delay NEXT IF up=1 THEN TargetUp 'Heads toward the target 500 steps GOTO TargetDown TargetUp: FOR i = 1 TO 500 PINS=%00001010 PAUSE Delay PINS=%00001100 PAUSE Delay PINS=%00000101 PAUSE Delay PINS=%00000011 PAUSE Delay NEXT GOTO DropEgg TargetDown: FOR i = 1 TO 500 PINS=%00001010 PAUSE Delay PINS=%00000011 PAUSE Delay PINS=%00000101 PAUSE Delay PINS=%00001100 PAUSE Delay NEXT GOTO DropEgg DropEgg: PIN4 = 1 PAUSE 5000 'Leaves pin4 on for 5sec (5000ms) PIN4 = 0 GOTO Evacuate Evacuate: IF up=1 EvacuateUp GOTO EvacuateDown EvacuateUp: FOR i = 1 TO 10000 PINS=%00001010 PAUSE Delay PINS=%00001100 PAUSE Delay PINS=%00000101 PAUSE Delay PINS=%00000011 PAUSE Delay NEXT EvacuateDown: FOR i = 1 TO 500 PINS=%00001010 PAUSE Delay PINS=%00000011 PAUSE Delay PINS=%00000101 PAUSE Delay PINS=%00001100 PAUSE Delay NEXT

Dave Paton

I'd try to increase the value of delay. That will slow the stepper down and push it towards the high torque end of it's performance curve. Keep us posted

-dave

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
This is not a sig. This is a duck. Quack.