Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: robonoob on December 06, 2007, 11:17:31 AM

Title: Hi me again with my stupid questions :D:D
Post by: robonoob on December 06, 2007, 11:17:31 AM
hi :) i wanted to ask you guys what is the difference of a microcontroller and a control board?
and i also want to know thats is it possible that i just buy myselt a control board or microcontroller (or i dont know which) and servos and then just put them together , then programme it and do i have a robot then? :D
so what i mean can i get a robot without soldering anything?
Title: Re: Hi me again with my stupid questions :D:D
Post by: Rebelgium on December 06, 2007, 02:09:51 PM
A microcontroller is a chip you can program.
A control board is a PCB with a microcontroller on it, among other things. (connectors etc.)

Yes you can plug servo's into a controlboard, and you can have a robot without soldering anything.
You can't plug a motor into a controlboard though, (it can't give enough juice).
Title: Re: Hi me again with my stupid questions :D:D
Post by: robonoob on December 06, 2007, 02:18:57 PM
Yes you can plug servo's into a controlboard, and you can have a robot without soldering anything.
You can't plug a motor into a controlboard though, (it can't give enough juice).
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what do u mean by that? i can plug a servo but i cant plug a motor? :D whats the difference between these two? :D(sorry for my stupidity)
Title: Re: Hi me again with my stupid questions :D:D
Post by: Rebelgium on December 06, 2007, 02:24:14 PM
put a little effort in, search google and this forum.
Title: Re: Hi me again with my stupid questions :D:D
Post by: Ro-Bot-X on December 07, 2007, 12:20:45 AM
There are controll boards with servo ports and motor ports available. If you need one of those, take a look at Orangutan board from Pololu.
Title: Re: Hi me again with my stupid questions :D:D
Post by: robonoob on December 08, 2007, 03:14:39 AM
There are controll boards with servo ports and motor ports available. If you need one of those, take a look at Orangutan board from Pololu.
whats the difference between motors and servos i still don't get it :D
Title: Re: Hi me again with my stupid questions :D:D
Post by: bens on December 08, 2007, 04:39:54 AM
Servos contain three key parts: a motor/gearbox, a potentiometer used for motor position feedback, and integrated control circuitry.  A servo has three wires: power, ground, and signal.  You send pulses over the signal wire, and the width of the pulse tells the servo's motor to move to a corresponding position.  Servos can be modified for continuous rotation, in which case the signal pulse width determines to the servo's rotational velocity rather than its position.

A motor is much simpler than a servo.  It has two leads across which you apply a voltage.  The speed of the motor depends on the magnitude of this potential difference, and the direction of the motor depends on the direction of the potential difference.  Motors have no integrated control circuitry.  Instead, you typically control them with a motor driver (usually an H-bridge circuit) or a motor controller (a higher level device that uses an H-bridge to control a motor in response to some analog/RC/serial input).
Title: Re: Hi me again with my stupid questions :D:D
Post by: robonoob on December 08, 2007, 03:25:00 PM
Servos contain three key parts: a motor/gearbox, a potentiometer used for motor position feedback, and integrated control circuitry.  A servo has three wires: power, ground, and signal.  You send pulses over the signal wire, and the width of the pulse tells the servo's motor to move to a corresponding position.  Servos can be modified for continuous rotation, in which case the signal pulse width determines to the servo's rotational velocity rather than its position.

A motor is much simpler than a servo.  It has two leads across which you apply a voltage.  The speed of the motor depends on the magnitude of this potential difference, and the direction of the motor depends on the direction of the potential difference.  Motors have no integrated control circuitry.  Instead, you typically control them with a motor driver (usually an H-bridge circuit) or a motor controller (a higher level device that uses an H-bridge to control a motor in response to some analog/RC/serial input).
oh ok i get it...i have another question about that...i was thinking of making  the $50 robot and i was wandering that can i make the $50 robot with motors not servos? cuz motors are much cheaper than servos :D or will it cost more to me if i wanted to do it with motors? :D
Title: Re: Hi me again with my stupid questions :D:D
Post by: Ro-Bot-X on December 08, 2007, 03:39:56 PM
...can i make the $50 robot with motors not servos? cuz motors are much cheaper than servos :D or will it cost more to me if i wanted to do it with motors? :D
Yes, you can. Find 2 computer CD-Roms, take them apart, pull out the drawer motor and grears, buy an H bridge like L293D and you're set. After you have them, I'll show you the schematic and program modifications.
Title: Re: Hi me again with my stupid questions :D:D
Post by: Rebelgium on December 08, 2007, 04:49:09 PM
motors are cheaper than servo's, yes.
But to be able to use motors you have to buy motor drivers (H-bridges), and that makes using motor's (almost always) more expensive, and more complicated.
Title: Re: Hi me again with my stupid questions :D:D
Post by: ed1380 on December 08, 2007, 07:49:59 PM
umm. you can make your own h-bridge and there are ways to get parts cheap
Title: Re: Hi me again with my stupid questions :D:D
Post by: paulstreats on December 08, 2007, 08:12:13 PM
i think the idea behind using servo's on something like the $50 robot is to make the electronics part simple so everybody can understand it (not to mention mounting them to your chassis). If you go using motors, and then have to have an h-bridge circuit for each motor on the circuit built, then it's going to overwhelm newcomers to robotics.

You are probably best saving up a little longer and buying the servo's and then go from there.

You can use h-bridge and motors cheaper than servo's but you also need a fundemental knowledge of the electronics involved to understand it.(whats the point in building something you dont understand)
Title: Re: Hi me again with my stupid questions :D:D
Post by: robonoob on December 09, 2007, 03:57:49 AM
umm. you can make your own h-bridge and there are ways to get parts cheap
if u mean scavenging then yea this is cheap way to get parts :D but is there any other way you ment? :D
Title: Re: Hi me again with my stupid questions :D:D
Post by: airman00 on December 09, 2007, 07:37:25 AM

umm. you can make your own h-bridge
an h bridge is basically 4 MOSFETs , and its a fairly simple circuit


there are ways to get parts cheap
Free samples , scavenging , eBay , surplus stores