MOSFET chopper controlled by 8051

JohnInTX

Joined Jun 26, 2012
4,787
Not for this but there are various PC-based oscilloscopes out there that have a front end that connects to the PC/software via USB. I haven't used any but there has been some discussion on them here at AAC. Search on USB Oscilloscope. The few threads I scanned lean towards a real scope. Rigol and Hantek were some brands mentioned but I don't know much about them (I use Tek).
 

Thread Starter

Anirban Raha

Joined Dec 4, 2013
70
After going though all the info that you have provided...I tried the circuit with a few mods and its working satisfactorily...seems all it needed was twisting the motor wires...and a orienting the RF module away from power lines...but...will this circuit work if I use 4 motors? I mean..does 4 motors mean 4x the noise? What other modifications should I think of? Please help!!!
 

JohnInTX

Joined Jun 26, 2012
4,787
After going though all the info that you have provided...I tried the circuit with a few mods and its working satisfactorily...seems all it needed was twisting the motor wires...and a orienting the RF module away from power lines...but...will this circuit work if I use 4 motors? I mean..does 4 motors mean 4x the noise? What other modifications should I think of? Please help!!!
If one is working and you've taken all the precautions to quiet things down, try one more motor. For now, you can run both off the same PWM line from the uC. If that works, go ahead and wire up all 4. You can still run them all off one PWM to keep firmware and hardware issues separate. If you have trouble remember that in addition to more potential noise from the additional motors, power supply and grounding issues will be magnified due to the higher currents involved.

If we have identified all of the major issues, adding motors should just involve replicating the driver/motor circuit and powering them in the correct way.

Noise considerations:
It may turn out that a particular motor has more noise than the others. If so, swap it in and out to isolate the offender then see what can be done about it.

If you run into other troubles, the same approaches we used before apply - isolate the cause then deal with it.

Once all 4 are happy, check your RF situation by moving the receiver around to see if you are truly out of any interference situations or if you just got lucky with 1 motor.

When you are satisfied that you can reliably control 4 motors off the single PWM, you can look at coding separate PWM outputs from your single uC.

Good luck.
 

Thread Starter

Anirban Raha

Joined Dec 4, 2013
70
The hardware is complete...I'm able to run 4 motors at full load(8Ax4=32A) without any interference...and on a perf-board...this is working even without twisting the motor wires...but I will keep them twisted anyway...
Now I want to move onto the next part of my project...I want to improve the programming and include sensors(gyro and accelerometer) to make it a closed loop system...I have looked up a 6 axis gyro and accelerometer sensor IC MPU6050...please tell me your thoughts about it...I have decided to shift to AtMega16 which has inbuilt PWM generators. Is it possible to interface ATMega16 with this sensor? If yes, please help me with it as I have never worked with AtMega uCs.
P.S. Should I start a new thread?
http://www.google.co.in/url?sa=t&rc...vE707bN2IH3I6KmqQ&sig2=K65OT3j1TaA4dHUI47fF1Q
 
Top