Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

remote control

Status
Not open for further replies.

mohsinans

New Member
hey i wana make a remote controlled car robot.......i have all the motors and the chasis but no knowledge abt RCs. i wana contol two motors with the help of a remote control....plz help me by telling me which circuit do i need to control the switching of the motors......i jus need to make the motor run and stop by switching mechanism....i.e i need to control the switch with help of a remote control...plz help me.... :(
 
Motors are switched on/off and reversed using H-Bridges.

The H-Bridge is often controlled by a micro controller.

The micro controller interfaces with a radio receiver.

This is too complex for a first project. But you can get there if you are willing to spend the hours to learn what is needed.

Suggest you start with the sticky post at the start of the mnicrocontroller forum. Start with getting an LED to blink. :D
 
i dont want a reverse action for the motors.......and do i need radio reciever for conrolling the motors...meaning that cant i use a infrared led and sensor to control the operation....like in case of remote controls for TVs ( forgive my ignorance but this was the approach i was thinking of....:(
 
You do not read a radio if you are using IR.

If you only want on/off motor control you can use a SPST relay. For reversing you can use a DPDT relay. the relays may cost more then the PWM chip.

H-Bridge is a fancy name for transistors used to control a motor. It is able to switch the motor on and off very fast to provide less the full speed. This is know as PWM or Pulse Wave Modulation (google for details on PWM and H-Bridge). A chip to do PWM for 2 motors can be had for about $3-$5.


The IR receiver converts the input from the IR remote to a bunch of 0's and 1's. It takes a micro controller to decode the bit stream. It is up to you to assign actions (in your computer code) to the decoded info.

It may be possible use logic chips instead of a micro controller but it would be much more work and more expensive. (big time)

There are ways to build a remote control system without a micro controller but none that I know of that will work with IR from a standard TV remote. If you only need one channel you could use a radio to transmit a PWM signal and run that into a servo (again google) but only buys you one channel. There are ways to get more then one channel doing this but it gets more and more convoluted.

Easier to do IR->microController->H-Bridge. There is a lot to learn but it is fun. And there are people here to help. It is all very cool/neat/(insert local expression) stuff.
 
3v0 said:
H-Bridge is a fancy name for transistors used to control a motor. It is able to switch the motor on and off very fast to provide less the full speed.

A bit misleading, an H-Bridge is just to allow switching the motor both ways, it's got nothing to do with 'switching fast' for PWM as such.

This is know as PWM or Pulse Wave Modulation (google for details on PWM and H-Bridge). A chip to do PWM for 2 motors can be had for about $3-$5.

Again, two unrelated subjects really, PWM works just the same with a single ended driver and no H-Bridge - and it's commonly done that way, using a DPDT relay to replace the H-Bridge (for reversing), and a single transistor (or FET) for the PWM.

So don't get confused, an H-Bridge and PWM are completely different things, but are often used together.
 
I asked the OP to Google for info on the subjects H-Bridge and PWM. I based the rest of the post on his doing so.

Had I not asked him to Google I would have written this. Maybe I should have regardless.

H-Bridge is a fancy name for transistor based circuit used to control a motor. It enables DC motors to be run forwards or backwards.

To run a DC motor at less then full speed it is rapidly switched on and off. This is know as Pulse Width Modulation or PWM. A PWM signal is most often provided by a uC or other circuitry. A PWM signal generated by a uC is not sufficient to drive a motor directly.

A H-Bridge can drive a DC motor directly and switch the motor on and off rapidly. This is ideal for use with a PWM input for DC motor speed control.

A H-Bridge can provide the reversing function and fast switching for use with PWM in a single package. A H-Bridge for 2 motors can be had for about $3-$5.
 
ok, so what I'm understanding, is that you want an RC Robot, right?
Well, I'm an RC expert! I have numerous hobby level RC cars (nitro cars, electric cars, and 50+ mph cars!)
What you need to do, is buy your self a reciever and remote (RX, and TX) If you only want to run two motors/servos, you will only need a 2 channel set, but if you want to run more (ie, controlled lights, more motors/servos) you need more channels. You can buy these remotes fairly cheaply, but if you are running motors, you are going to need a ESC (electronic Speed Control).
This is most likey making no sense to you, but if you are interested in what i'm saying, just pm me, and I can get you links to these parts.
 
i m from India and the cost of transmitter and receiver is much high here......so i go to buy some small toy car with remote and then need to modify it according to my needs....i guess those cars have very less power ratings so i need to replace motors to get more powerful motors.........can someone tell me what components i need to replace in order to have a more powerful motor attached to the same circuit...........and also if i want to make the circuit run at some other frequency, what all things i need to change or need to know.......i hope people getting what i m trying to do here
 
A cheap litrtle RC toy car has a cheap radio circuit that has a short range.
Excellent radio control transmitters and receivers are inexpensive in the civilized world.
 
thanx audio guru for your delightfull msg.........that was a great help..........neways for all other serious robotic gurus out there.......if you could be much more practical than this guy and help me out in the doubt that i asked.........plz reply
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top