controlling servomotors
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Posts: 46,084
I have built a robotic hand with 8 degrees of freedom , driven by
servomotors. Would I be able to use a basic stamp2 to control the 8
motors to achieve 'simultaneous ' movemment of the finger joints ,
i.e., 'near simultaneous' , ( < 20 / 8 milliseconds , to update all 8
position commands ? ) ? I wish to use a PC as a user interface ,
to enable the user to select from various motion sequences .
Would you recommend using a driver board , as i dont have time to
design my own ? I am aware of two such boards , the Parallax mini
SSCII , and the Milford Instruments 'serial servo driver board' ,
(http://www.milinst.demon.co.uk/ssc_bord.htm) Using a PC as user
interface , would either/both of these boards be suitable for the
task? What are the main advantages of using stampII rather than stampI
in this application ?
I would be most grateful for any design advice ,
Many thanks ,
Michael Hilton
servomotors. Would I be able to use a basic stamp2 to control the 8
motors to achieve 'simultaneous ' movemment of the finger joints ,
i.e., 'near simultaneous' , ( < 20 / 8 milliseconds , to update all 8
position commands ? ) ? I wish to use a PC as a user interface ,
to enable the user to select from various motion sequences .
Would you recommend using a driver board , as i dont have time to
design my own ? I am aware of two such boards , the Parallax mini
SSCII , and the Milford Instruments 'serial servo driver board' ,
(http://www.milinst.demon.co.uk/ssc_bord.htm) Using a PC as user
interface , would either/both of these boards be suitable for the
task? What are the main advantages of using stampII rather than stampI
in this application ?
I would be most grateful for any design advice ,
Many thanks ,
Michael Hilton
Comments
8 servo's consecutively achieving virtually simultaneous motion. The mini
SSC is from Scott Edwards Electronics. Go here to get more info on it
http://www.seetron.com/ssc.htm.
Mike.
Original Message
From: michael [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=03_Ly1DmM6AfqQi8iaekYuEX8Ip26rO5NFMVv_mBQkDxSWErEtl5HVQolX9ktw04AEVNjsKjJaqnklU5EgxpIg]mjh@c...[/url
Sent: Tuesday, July 11, 2000 7:03 AM
To: basicstamps@egroups.com
Subject: [noparse][[/noparse]basicstamps] controlling servomotors
I have built a robotic hand with 8 degrees of freedom , driven by
servomotors. Would I be able to use a basic stamp2 to control the 8
motors to achieve 'simultaneous ' movemment of the finger joints ,
i.e., 'near simultaneous' , ( < 20 / 8 milliseconds , to update all 8
position commands ? ) ? I wish to use a PC as a user interface ,
to enable the user to select from various motion sequences .
Would you recommend using a driver board , as i dont have time to
design my own ? I am aware of two such boards , the Parallax mini
SSCII , and the Milford Instruments 'serial servo driver board' ,
(http://www.milinst.demon.co.uk/ssc_bord.htm) Using a PC as user
interface , would either/both of these boards be suitable for the
task? What are the main advantages of using stampII rather than stampI
in this application ?
I would be most grateful for any design advice ,
Many thanks ,
Michael Hilton
(automatc doors) using two servo motors i maneged to make them both move
at the same time. if you want to use a pc to move them then there is a
dick that you can buy (sold by the same people) that will record the
movments so you can play them back at a later date
michael wrote:
> I have built a robotic hand with 8 degrees of freedom , driven by
> servomotors. Would I be able to use a basic stamp2 to control the 8
> motors to achieve 'simultaneous ' movemment of the finger joints ,
> i.e., 'near simultaneous' , ( < 20 / 8 milliseconds , to update all 8
> position commands ? ) ? I wish to use a PC as a user interface ,
> to enable the user to select from various motion sequences .
>
> Would you recommend using a driver board , as i dont have time to
> design my own ? I am aware of two such boards , the Parallax mini
> SSCII , and the Milford Instruments 'serial servo driver board' ,
> (http://www.milinst.demon.co.uk/ssc_bord.htm) Using a PC as user
> interface , would either/both of these boards be suitable for the
> task? What are the main advantages of using stampII rather than stampI
> in this application ?
>
> I would be most grateful for any design advice ,
> Many thanks ,
> Michael Hilton
One thing you might consider is the PAK-VIII -- this chip allows you to
generate 8 channels of pulse output. You control the "on" time, the "off"
time and optionally, a count of pulses.
While you could interface the device to a PC, it uses our PAK protocol,
which is very easy to work with from a Stamp or most other microcontrollers.
RC servos usually require an "on" pulse of 1500uS to stay centered and then
some length of time before you have to pulse it again. The PAK-VIII can
easily handle this.
You can read more at http://www.al-williams.com/awce/pak8.htm
Regards,
Al Williams
AWC
* Floating point math for the Stamp, PIC, SX, or any microcontroller:
http://www.al-williams.com/awce/pak1.htm
>
Original Message
> From: michael [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=TcPY9qm14K2gkBLIcAysTIb2dgCh4O3N684WyqHzv5sARGPE2q6Fn1jWl4jj67Byi131ATpTG5lxy1xTFZ1ZtQ]mjh@c...[/url
> Sent: Tuesday, July 11, 2000 9:03 AM
> To: basicstamps@egroups.com
> Subject: [noparse][[/noparse]basicstamps] controlling servomotors
>
>
> I have built a robotic hand with 8 degrees of freedom , driven by
> servomotors. Would I be able to use a basic stamp2 to control the 8
> motors to achieve 'simultaneous ' movemment of the finger joints ,
> i.e., 'near simultaneous' , ( < 20 / 8 milliseconds , to update all 8
> position commands ? ) ? I wish to use a PC as a user interface ,
> to enable the user to select from various motion sequences .
>
> Would you recommend using a driver board , as i dont have time to
> design my own ? I am aware of two such boards , the Parallax mini
> SSCII , and the Milford Instruments 'serial servo driver board' ,
> (http://www.milinst.demon.co.uk/ssc_bord.htm) Using a PC as user
> interface , would either/both of these boards be suitable for the
> task? What are the main advantages of using stampII rather than stampI
> in this application ?
>
> I would be most grateful for any design advice ,
> Many thanks ,
> Michael Hilton
>
>
>
>
>
>
controls makes an excellent software/hardware card system for driving RC
servos. It can simultaneously drive up to 30 servos with high (~11 bit)
resolution positioning. The software has all kinds of sophisticated
graphing and editing functions, the best I've seen for this kind of
application. It's about $2k...
Duncan