Choosing RC Servo Controller
Bookmark this page:
 Yahoo!
 Google
 Windows Live
 del.icio.us
 digg
 Netscape
|
|
Posted by on July 15, 2008, 9:24 am
Please log in for more thread options I hope this is the correct group for my enquiry. I need to integrate an RC servo motor into my project and I'm trying to find the best way to control it. I'm unable to generate the PWM control signal myself so I'm need to buy a servo controller. I don't have any serial comms available, however, only digital IO lines. The only servo controllers I've found so far are controlled via 232 (or USB) - does anyone know of any controllers that I could control with digital IO? For example, one pin to turn movement on/off, one pin to set direction. Something simple like that. I've got sensors that provide position feedback so I know when to stop the movement (but I don't necessarily know exactly where that position will be). Any help would be much appreciated! Thanks, Rob | ||||
|
Posted by John Mianowski on July 15, 2008, 9:45 am
Please log in for more thread options It's pretty easy to generate PPM (not PWM) signals to control a hobby servo with just a 555 & a couple of resistors & capacitors. A potentiometer can be used to vary the pulse width. It's also pretty easy to do with any microcontroller. What kind of "digital IO" do you have in mind? Google "serial", "servo", & "controller" for a huge selection of OTS products. JM | ||||
|
Posted by Martin Brown on July 15, 2008, 10:23 am
Please log in for more thread options John Mianowski wrote:
> On Jul 15, 8:24 am, rgagarr...@gmail.com wrote:
>> Hi,
>> I hope this is the correct group for my enquiry. >> >> I need to integrate an RC servo motor into my project and I'm trying >> to find the best way to control it. I'm unable to generate the PWM >> control signal myself so I'm need to buy a servo controller. I don't >> have any serial comms available, however, only digital IO lines. You could control an RC servo by wiggling a digital IO line up and down in the right fashion. >> only servo controllers I've found so far are controlled via 232 (or
>> USB) - does anyone know of any controllers that I could control with >> digital IO? For example, one pin to turn movement on/off, one pin to >> set direction. Something simple like that. I've got sensors that >> provide position feedback so I know when to stop the movement (but I >> don't necessarily know exactly where that position will be). >> >> Any help would be much appreciated! Hang on lets take a step back. It sounds more like you could use a stepper motor driver than a servo. What are you trying to do? >
> It's pretty easy to generate PPM (not PWM) signals to control a hobby > servo with just a 555 & a couple of resistors & capacitors. A > potentiometer can be used to vary the pulse width. It's also pretty > easy to do with any microcontroller. What kind of "digital IO" do you > have in mind? > > Google "serial", "servo", & "controller" for a huge selection of OTS > products. Although a bit of software could generate the right waveforms. ISTR Nominally 50Hz rep rate with a 1-2ms pulse to indicate requested position. Plenty of hobby PIC based sample code out there. Regards, Martin Brown ** Posted from http://www.teranews.com ** | ||||
|
Posted by Phil Allison on July 16, 2008, 6:09 am
Please log in for more thread options
>
> In the light of the responses here I think the easiest thing for me to > do is to build my own controller using a 555 chip which I can control > via the IO lines. I know this should be straight forward, ** Sounds like a plan .... ..... Phil | ||||
|
Posted by Frank Buss on July 16, 2008, 9:24 am
Please log in for more thread options rgagarrett@gmail.com wrote:
> The valve is moved with an RC servo
> motor. The motor drive electronics includes some 0-5V digital IO > lines, but they're not suitable for creating the PPM signal required > for the servo motor. Do you mean a PWM signal? PPM signals are used for remote controls for RC models, but a RC servo motor usually is controlled with a PWM signal, like described in the other posting and which you can see here: http://www.mp.ttu.ee/risto/rc/electronics/radio/signal.htm > In the light of the responses here I think the easiest thing for me to
> do is to build my own controller using a 555 chip which I can control > via the IO lines. I know this should be straight forward, but I > didn't know whether there was a controller board already out there > that does what I want. If you need two different pulse widths, which you can switch with a digital signal, I would use a microcontroller, e.g. the PIC12F508, which you can buy for $1.25. The program is about 100 lines of assembler, including comments and the output pulse can be adjusted with 64 us resolution: http://www.frank-buss.de/PICDigitalServo/index.html -- Frank Buss, fb@frank-buss.de http://www.frank-buss.de, http://www.it4-systems.de | ||||
| Similar Threads | Posted |
| Choosing RC Servo Controller | July 15, 2008, 9:24 am |
| Motor Controller Stepper/Servo with Feed Back | December 17, 2007, 1:46 pm |
| analogue P(ID) controller to digital PID controller | April 20, 2007, 5:55 am |
| Servo Issue | August 1, 2005, 4:13 am |
| DC Servo Motor Drive | December 23, 2005, 2:10 am |
| Servo motor chip | January 18, 2006, 4:03 pm |
| Are there any ICs (non-programmable) to control a Servo? | August 14, 2006, 11:32 pm |
| servo control via lpt problems | March 21, 2007, 7:02 pm |
| 100Amps or more brushless servo amplifiers? | January 18, 2005, 8:19 am |
| Finding pinout of a servo encoder? | April 15, 2005, 12:57 pm |
| Brushed Servo Motor Driver: 3A | August 5, 2005, 1:58 pm |
| RFD: optical.servo.coin.marker | August 10, 2005, 2:33 am |
| Honeywell KS270C servo - looking for schematics | September 27, 2005, 3:37 pm |
| "PWM based DC Servo Motor Control" | January 11, 2006, 10:33 pm |
| servo motor drive 3 phase | May 23, 2006, 8:57 pm |
> I hope this is the correct group for my enquiry.
>
> I need to integrate an RC servo motor into my project and I'm trying
> to find the best way to control it. I'm unable to generate the PWM
> control signal myself so I'm need to buy a servo controller. I don't
> have any serial comms available, however, only digital IO lines. The
> only servo controllers I've found so far are controlled via 232 (or
> USB) - does anyone know of any controllers that I could control with
> digital IO? For example, one pin to turn movement on/off, one pin to
> set direction. Something simple like that. I've got sensors that
> provide position feedback so I know when to stop the movement (but I
> don't necessarily know exactly where that position will be).
>
> Any help would be much appreciated!
>
> Thanks,
> Rob