Hello everyone,
I am making a line follower robot for my varsity project show. But the problem is every time the motor starts voltage from power supply drops significantly.
I think this happens because of motor noise. but i cant control it. what should i do? Should i use capacitors? If so what value should i use?

I must mention, i am using Pic18452 micro controller and L293d motor driver for my two motors.

Please help me. I am near my deadline.

 

Hello,

The l293d will probably be not capable of driving the motor.

Read this thread for some suggestions:
http://forum.allaboutcircuits.com/showthread.php?t=68605

Bertus

 

Thank you for your reply Bertus. But i am using only two 12 volt dc motor. I knew L293d can run this type of small motors. If not what else should I use?

 

Hello,

Can you post a current schematic?
Do you also have the specs of the motor to use?

Bertus

 

Here is my schematic on proteus7.7 I do not understand what you meant by the specs of the motor to use.

 

what type of filter are being used in the power supply ?

Hello everyone,
I am making a line follower robot for my varsity project show. But the problem is every time the motor starts voltage from power supply drops significantly.
I think this happens because of motor noise. but i cant control it. what should i do? Should i use capacitors? If so what value should i use?

I must mention, i am using Pic18452 micro controller and L293d motor driver for my two motors.


Please help me. I am near my deadline.

 

Hello,

I can not open the proteus file.
Can you post a screenshot in .png format?

Bertus

 

I have sent the screen shot.

 

Hello,

What is powering the MCU?
What is the input voltage of the 7812?
Are there capacitors mounted on the input and output of the 7812?
You should use a 0.33 μF at the input and 0.1 μF at the output of the 7812, to avoid oscillating of the 7812.

Bertus

 

Simple solution. Power the MCU from a separate battery, not on the same battery that is supplying the motor.

 

Simple solution. Power the MCU from a separate battery, not on the same battery that is supplying the motor.

I have tried that already but didn't work.

 

Hello,

What is powering the MCU?
What is the input voltage of the 7812?
Are there capacitors mounted on the input and output of the 7812?
You should use a 0.33 μF at the input and 0.1 μF at the output of the 7812, to avoid oscillating of the 7812.

Bertus

At first I used a 24v adapter. 7805 and 7812 was connected in parallel for MCU and motor respectively. After having problem i tried separate 12v batteries but that didnt work too.

 

what type of filter are being used in the power supply ?

I haven't used any filter yet. What should i use as filter and where?

 

Though the problem was posted a long time ago, the problem was occurred same to me. I have solved this problem using gear. It will reduce rpm but increase torque. So, at loaded condition it may move too.