# motor wheel stops when placed on ground

hi i m using 2 9v dc motors for moving my robotic car. ut problem is when i placed it on ground wheels does not moving although it is being operated by the 9v battery supply.

That's perfectly understandable, small 9V batteries are hopeless at powering motors which need an amp or two - you need a pack of AA rechargable batteries which can push out amps and hold up their voltage under load.

small 9V batteries are designed for 20to 50mA of load, not 2A.

What sort of motor driver are you using?

MarkT: That's perfectly understandable, small 9V batteries are hopeless at powering motors which need an amp or two - you need a pack of AA rechargable batteries which can push out amps and hold up their voltage under load.

small 9V batteries are designed for 20to 50mA of load, not 2A.

So i need a pack of batteries to make that equal to 9v ?? that 9v can give enough amp that can run the wheels ??

groundfungus: What sort of motor driver are you using?

L293D

You need batteries for at least 9 V. The L293 drops about 2 V so with 9 V supply the motors will see around 7V.

groundfungus: You need batteries for at least 9 V. The L293 drops about 2 V so with 9 V supply the motors will see around 7V.

i m already using 9V battery

adeel_52: So i need a pack of batteries to make that equal to 9v ?? that 9v can give enough amp that can run the wheels ??

After that comment this next one doesn't make much sense

...R

FYI, A 9V PP3 smoke alarm battery is rated at about 500mAh , meaning that it will power a 100 mA load for about 5 hours. It does not necessarily mean that it will power a 500mAh load for 1 hour, although it may be possible. (I have not tried it). Either way, a 9V battery in a toy car , when placed on the ground , would only be able to propel the car if the car had been designed with gears to reduce the load on the battery.

hi i m using 2 9v dc motors for moving my robotic car.

this statement suggests that you create this car, totally oblivious to the internal resistance of a 9V battery and the implications of that with respect to your load (which you have not told us in ounces or grams). This post is not going to get anywhere until you post a schematic and if an arduino is involved, the code. We will also need a link or datasheet for your motors and how you wired your L293. Do you have a multimeter (DMM) ? Do you have any experience (with anything related) ?

If the motors are rated as 9V motors then as you loose 2 to 3V in the driver you are not powering the motor with enough voltage. You need to add a few more AA batteries so that the motor "sees" the voltage it is expecting.

you need a 6-pack of AA rechargable batteries which can push out amps and hold up their voltage under load.

raschemmel:

you need a 6-pack of AA rechargable batteries which can push out amps and hold up their voltage under load.

Not quite the same thing.

I am suggesting that for a 9V motor he needs to power it with 12V if he has any hope for the motor to actually receive 9V.

I'd like to see a mechanical drawing of the "car" - or at least a picture of it. I am suspecting the wheels are directly connected to the shafts of the motors, instead of through a gear box, which raschemmel hinted at...

raschemmel: FYI, A 9V PP3 smoke alarm battery is rated at about 500mAh , meaning that it will power a 100 mA load for about 5 hours. It does not necessarily mean that it will power a 500mAh load for 1 hour, although it may be possible. (I have not tried it). Either way, a 9V battery in a toy car , when placed on the ground , would only be able to propel the car if the car had been designed with gears to reduce the load on the battery.

hi i m using 2 9v dc motors for moving my robotic car.

this statement suggests that you create this car, totally oblivious to the internal resistance of a 9V battery and the implications of that with respect to your load (which you have not told us in ounces or grams). This post is not going to get anywhere until you post a schematic and if an arduino is involved, the code. We will also need a link or datasheet for your motors and how you wired your L293. Do you have a multimeter (DMM) ? Do you have any experience (with anything related) ?

yeah i m using arduino and simply using dc motor by putting it in the tyres

Is there any reduction gearing? You definitely need it...