Radio Control and DC motors
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Posts: 46,084
Hello,
I'm trying to radio control my robot using a Futaba Radio Control
system (6EXA).
The problem is that I have to control two DC motors separately and
not one motor for direction and another for movement (Like an Army
Tank).
I think that the solution might be to use a BS (BS2SX) to translate
the PWM of the futaba receiver for the Left-Right Channel and the PWM
for the speed to two different outputs each for a DC motor. What do
you think? Have you any better idea.
Thanks in advance.
+
+
| |
| FUTABA RECEIVER |
| |
+
+
+----+
| |
|LEFT-RIGHT |SPEED
|CHANNEL |
| |
+
+
+
+
| |
| BS2SX |
| |
+
*
*
+
LEFT MOTOR * * RIGHT MOTOR
* *
+---*
*----+
| H-BRIDGE |
+-+
+-+
| |
| |
--+-- --+--
// \\ // \\
| | | |
\\ // \\ //
LEFT MOTOR RIGHT MOTOR
I'm trying to radio control my robot using a Futaba Radio Control
system (6EXA).
The problem is that I have to control two DC motors separately and
not one motor for direction and another for movement (Like an Army
Tank).
I think that the solution might be to use a BS (BS2SX) to translate
the PWM of the futaba receiver for the Left-Right Channel and the PWM
for the speed to two different outputs each for a DC motor. What do
you think? Have you any better idea.
Thanks in advance.
+
+
| |
| FUTABA RECEIVER |
| |
+
+
+----+
| |
|LEFT-RIGHT |SPEED
|CHANNEL |
| |
+
+
+
+
| |
| BS2SX |
| |
+
*
*
+
LEFT MOTOR * * RIGHT MOTOR
* *
+---*
*----+
| H-BRIDGE |
+-+
+-+
| |
| |
--+-- --+--
// \\ // \\
| | | |
\\ // \\ //
LEFT MOTOR RIGHT MOTOR
Comments
-- but it can be done. What you have to do is create a program that
runs a tight loop so you can synthesize the PWM signal to the motors.
In that loop you'll use PULSIN to read the servo signal from your
reciever; from that you'll determine direction control and speed for
your synthesized PWM.
The docs for the NX-1000-24/40 show how to control motor speed and
direction with synthesized PWM (using the onboard L272 driver). That
code should help you.
http://www.parallax.com/detail.asp?product_id=28137
-- Jon Williams
-- Applications Engineer, Parallax
-- Dallas Office
Original Message
From: emm_frag [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=IZmDacAEbD1vhaAMCno7INa2dbFa3mzoeDGKzCd_pAj2mRqDM4zbeYuaWO-aam6qAZKvWGkfjA]emm_frag@y...[/url
Sent: Saturday, April 03, 2004 6:12 AM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] Radio Control and DC motors
Hello,
I'm trying to radio control my robot using a Futaba Radio Control
system (6EXA).
The problem is that I have to control two DC motors separately and
not one motor for direction and another for movement (Like an Army
Tank).
I think that the solution might be to use a BS (BS2SX) to translate
the PWM of the futaba receiver for the Left-Right Channel and the PWM
for the speed to two different outputs each for a DC motor. What do
you think? Have you any better idea.
Thanks in advance.
+
+
| |
| FUTABA RECEIVER |
| |
+
+
+----+
| |
|LEFT-RIGHT |SPEED
|CHANNEL |
| |
+
+
+
+
| |
| BS2SX |
| |
+
*
*
+
LEFT MOTOR * * RIGHT MOTOR
* *
+---*
*----+
| H-BRIDGE |
+-+
+-+
| |
| |
--+-- --+--
// \\ // \\
| | | |
\\ // \\ //
LEFT MOTOR RIGHT MOTOR
You have a 6 channel Radio control system and you want to control
two DC motors separately?
I would say, hook up one engine to the left stick and one engine to
the right stick. No stamp needed
For controlling the DC motors you can use any PWM controller (you'll
need two controllers or one 2-engine controller) that can handle the
power of the DC motors.
If you want to steer the two engines configured in a tank-layout in
the normal left/right and forward/backward style you might find the
6EXA capable of doing this.
--- In basicstamps@yahoogroups.com, "emm_frag" <emm_frag@y...> wrote:
> Hello,
> I'm trying to radio control my robot using a Futaba Radio Control
> system (6EXA).
> The problem is that I have to control two DC motors separately and
> not one motor for direction and another for movement (Like an Army
> Tank).
> I think that the solution might be to use a BS (BS2SX) to translate
> the PWM of the futaba receiver for the Left-Right Channel and the
PWM
> for the speed to two different outputs each for a DC motor. What do
> you think? Have you any better idea.
> Thanks in advance.
>
>
> +
+
> | |
> | FUTABA RECEIVER |
> | |
> +
+
+----+
> | |
> |LEFT-RIGHT |SPEED
> |CHANNEL |
> | |
> +
+
+
+
> | |
> | BS2SX |
> | |
> +
*
*
+
> LEFT MOTOR * * RIGHT MOTOR
> * *
> +---*
*----+
> | H-BRIDGE |
> +-+
+-+
> | |
> | |
> --+-- --+--
> // \\ // \\
> | | | |
> \\ // \\ //
>
> LEFT MOTOR RIGHT MOTOR
I can use only one stick, the other is to control a camera which use
two servo for moving up-down, left-right.
So I have to translate the movement of two separate servos front-back
and left-right to a combination of left-right motor so for example
when the stick is in front-right position than means that the left
motor will move at full speed and the right motor at its half speed
so the vehicle will steer right. I hope to state my problem clearer
this time.
--- In basicstamps@yahoogroups.com, "Peter NL" <tfro@b...> wrote:
> I'm not getting it:
>
> You have a 6 channel Radio control system and you want to control
> two DC motors separately?
>
> I would say, hook up one engine to the left stick and one engine to
> the right stick. No stamp needed
>
> For controlling the DC motors you can use any PWM controller
(you'll
> need two controllers or one 2-engine controller) that can handle
the
> power of the DC motors.
>
> If you want to steer the two engines configured in a tank-layout in
> the normal left/right and forward/backward style you might find the
> 6EXA capable of doing this.
>
>
> --- In basicstamps@yahoogroups.com, "emm_frag" <emm_frag@y...>
wrote:
> > Hello,
> > I'm trying to radio control my robot using a Futaba Radio Control
> > system (6EXA).
> > The problem is that I have to control two DC motors separately
and
> > not one motor for direction and another for movement (Like an
Army
> > Tank).
> > I think that the solution might be to use a BS (BS2SX) to
translate
> > the PWM of the futaba receiver for the Left-Right Channel and the
> PWM
> > for the speed to two different outputs each for a DC motor. What
do
> > you think? Have you any better idea.
> > Thanks in advance.
> >
> >
> > +
+
> > | |
> > | FUTABA RECEIVER |
> > | |
> > +
+
+----+
> > | |
> > |LEFT-RIGHT |SPEED
> > |CHANNEL |
> > | |
> > +
+
+
+
> > | |
> > | BS2SX |
> > | |
> > +
*
*
+
> > LEFT MOTOR * * RIGHT MOTOR
> > * *
> > +---*
*----+
> > | H-BRIDGE |
> > +-+
+-+
> > | |
> > | |
> > --+-- --+--
> > // \\ // \\
> > | | | |
> > \\ // \\ //
> >
> > LEFT MOTOR RIGHT MOTOR
>Thanks for your answer,
>I can use only one stick, the other is to control a camera which use
>two servo for moving up-down, left-right.
>So I have to translate the movement of two separate servos front-back
>and left-right to a combination of left-right motor so for example
>when the stick is in front-right position than means that the left
>motor will move at full speed and the right motor at its half speed
>so the vehicle will steer right. I hope to state my problem clearer
>this time.
I'm by no means an expert with R/C but I would imagine that the camera movement
and the motor direction would not be occurring at exactly the same time. Thus, a
separate channel could be used as a "function" indicator. If that "function"
channel was active the motion commands would be routed to the motor controller,
and if it was off, the motion commands would be routed to the camera controller.
Hope that makes some sense, and partially answers your question.
Regards,
Bruce Bates
>Thanks for your answer,
>I can use only one stick, the other is to control a camera which use
>two servo for moving up-down, left-right.
>So I have to translate the movement of two separate servos front-back
>and left-right to a combination of left-right motor so for example
>when the stick is in front-right position than means that the left
>motor will move at full speed and the right motor at its half speed
>so the vehicle will steer right. I hope to state my problem clearer
>this time.
>
I think I understand your request.... I have a scheme that I have used
in the past that uses a very similar technique. What I have available
is a QuickBasic4.5 program that allows you to simulate the "Joystick"
position on the transmitter (with arrow keys). From here you should
be able to play with the values and get a desirable result. The two
horizontal bars represent a "Dead Band" where joystick activity is
ignored currently this is set to +/-50uS from Center equaling 1500uS
but can be adjusted for any value. There is a Gear option that I have
used in the past for HIGH or LOW gear designs. Simply described if your
joystick is on the edge or outside of the great circle then you are in
HIGH gear, otherwise you are in LOW gear. Electronically this would
switch in/out an extra battery pack or something to that effect depending
on what mode you were in.
ScreenShot:
http://www.angelfire.com/wizard/y2kbc/STAMPS/RC/rc_joy.gif
QuickBasic4.5 Program:
http://www.angelfire.com/wizard/y2kbc/STAMPS/RC/rc_joy.bas
Standalone EXE:
http://www.angelfire.com/wizard/y2kbc/STAMPS/RC/rc_joy.exe
Beau Schwabe Mask Designer National Semiconductor Corporation
500 Pinnacle Court, Suite 525
Home: polygon_man@h... Mail Stop GA1
Work: bschwabe@a... Norcross, GA 30071
helpful.
I also found this item that gives a simple and easy solution to the
problem:
http://www.robotlogic.com/product_imx1.html
Thanks anyway.
Manos
> I think I understand your request.... I have a scheme that I have
used
> in the past that uses a very similar technique. What I have
available
> is a QuickBasic4.5 program that allows you to simulate
the "Joystick"
> position on the transmitter (with arrow keys). From here you
should
> be able to play with the values and get a desirable result. The
two
> horizontal bars represent a "Dead Band" where joystick activity is
> ignored currently this is set to +/-50uS from Center equaling
1500uS
> but can be adjusted for any value. There is a Gear option that I
have
> used in the past for HIGH or LOW gear designs. Simply described
if your
> joystick is on the edge or outside of the great circle then you
are in
> HIGH gear, otherwise you are in LOW gear. Electronically this
would
> switch in/out an extra battery pack or something to that effect
depending
> on what mode you were in.
>
> ScreenShot:
> http://www.angelfire.com/wizard/y2kbc/STAMPS/RC/rc_joy.gif
> QuickBasic4.5 Program:
> http://www.angelfire.com/wizard/y2kbc/STAMPS/RC/rc_joy.bas
> Standalone EXE:
> http://www.angelfire.com/wizard/y2kbc/STAMPS/RC/rc_joy.exe
>
---
> Beau Schwabe Mask Designer National Semiconductor
Corporation
> 500 Pinnacle Court, Suite 525
> Home: polygon_man@h... Mail Stop GA1
> Work: bschwabe@a... Norcross, GA 30071
>
---
I'm trying to interface an RC receiver(Futaba) with a basic stamp
(BS2SX) so I need to convert the RC signal into bits some how. Can I
do it using the Pulsin command? Any connection schematics, is it
possible to connect the receiver directly with the I/O pins of my
stamp?
The reason for doing this is to control two DC motors, among other
things.
Thank you all.
a normally low signal, pulsing high (5V) for
1 to 2 mSec every 20 mSec. 1 mSec means
'all the way left', 2 mSec means 'all the
way right', and 1.5 mSec means 'Center'.
You should use 'PULSIN' to grab the signal
every 20 mSec or so (since it repeats, if
you miss a few pulses it should be no
big deal.)
Make sure your BS2 and the Futaba reciever
have a common ground, or you won't get
accurate readings.
--- In basicstamps@yahoogroups.com, "emm_frag" <manos@e...> wrote:
> Hello,
> I'm trying to interface an RC receiver(Futaba) with a basic stamp
> (BS2SX) so I need to convert the RC signal into bits some how. Can
I
> do it using the Pulsin command? Any connection schematics, is it
> possible to connect the receiver directly with the I/O pins of my
> stamp?
> The reason for doing this is to control two DC motors, among other
> things.
> Thank you all.