Controlling Different Servos (hi-tec)
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I need help with some servo basics! If I use this with a parallax
modified servo:
main:
forward:
for pulse_count = 1 to 100
pulsout 14, 500
pause 20
next
goto main
I can control the time that it goes and I can control the speed with
the pulsout (500) and the pause has little effect.
When I change the same variables with a different servo (for example
a HI-TEC servo that has been modified then the same variables have
very different effects on the behavior. Why is this!!! and how could
I make a Hi-TEC servo go slowly in one direction for a long period of
time (ie many continuous revolutions. Any help would be great.
-mike
modified servo:
main:
forward:
for pulse_count = 1 to 100
pulsout 14, 500
pause 20
next
goto main
I can control the time that it goes and I can control the speed with
the pulsout (500) and the pause has little effect.
When I change the same variables with a different servo (for example
a HI-TEC servo that has been modified then the same variables have
very different effects on the behavior. Why is this!!! and how could
I make a Hi-TEC servo go slowly in one direction for a long period of
time (ie many continuous revolutions. Any help would be great.
-mike
Comments
a slightly different neutral / center pulse value -- this is the point at
which a hacked servo will stop turning.
The pause has to do with refreshing the servo position every so often. If
send the PULSOUT command too often, the servo will jitter. If you don't send
it often enough the servo won't move properly.
Original Message
> I need help with some servo basics! If I use this with a parallax
> modified servo:
> main:
>
> forward:
> for pulse_count = 1 to 100
> pulsout 14, 500
>
> pause 20
> next
> goto main
>
> I can control the time that it goes and I can control the speed with
> the pulsout (500) and the pause has little effect.
>
> When I change the same variables with a different servo (for example
> a HI-TEC servo that has been modified then the same variables have
> very different effects on the behavior. Why is this!!! and how could
> I make a Hi-TEC servo go slowly in one direction for a long period of
> time (ie many continuous revolutions. Any help would be great.
hth
Leroy
Main:
forward:
for pulse_count = 125 to 250
pulsout 14, pulse_count
pause 20
next
goto main
Rodent wrote:
make it go faster and slower - Problem is that I changed all of th
evariables and cannot get it to go reverse - Any ideas?? Please.
btw I am using a huge hi-tec hs-805bb servo with a basic stamp2 and a
BOE and powering it with a radio shack 7.5v 2000ma battery which is
what was recommended - This power is going directly into th eboard
without using a harness but it seems to be fine as it is regulated
before getting to the stamp.
Thanks
--- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> Ever consider the following code, (slightly revised)..
>
>
> hth
>
> Leroy
>
> Main:
>
> forward:
>
> for pulse_count = 125 to 250
>
> pulsout 14, pulse_count
>
> pause 20
>
> next
>
> goto main
>
> Rodent wrote:
out the plastic stopper on the gear- I also have an unmodified one an
dwhen I use the code below it works fine (forward and backward)
'{$STAMP BS2}
pulse_count var word
low 14
main:
forward:
for pulse_count = 1 to 40
pulsout 14, 400
pause 20
next
pause 300
for pulse_count = 1 to 40
pulsout 14, 750
pause 20
next
pause 300
backsward:
for pulse_count = 1 to 40
pulsout 14, 1100
pause 20
next
pause 300
goto main
as an unmodified servo should....but once it is modified I cannot
get it to continutously go forward and backward....
--- In basicstamps@y..., "mafox67" <mafox@m...> wrote:
> That works great for going forward and I can adjust the pause and
> make it go faster and slower - Problem is that I changed all of the
> variables and cannot get it to go reverse - Any ideas?? Please.
> btw I am using a huge hi-tec hs-805bb servo with a basic stamp2 and
a
> BOE and powering it with a radio shack 7.5v 2000ma battery which is
> what was recommended - This power is going directly into th eboard
> without using a harness but it seems to be fine as it is regulated
> before getting to the stamp.
> Thanks
>
> --- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> > Ever consider the following code, (slightly revised)..
> >
> >
> > hth
> >
> > Leroy
> >
> > Main:
> >
> > forward:
> >
> > for pulse_count = 125 to 250
> >
> > pulsout 14, pulse_count
> >
> > pause 20
> >
> > next
> >
> > goto main
> >
> > Rodent wrote:
stopper on the gear) then it works fine as an unmodified servo (ie.
forward and backward) Once it is modified I cannot get it to go
continuously forward and backward.
--- In basicstamps@y..., "mafox67" <mafox@m...> wrote:
> Taht works great for going forward and I can adjust the pause and
> make it go faster and slower - Problem is that I changed all of th
> evariables and cannot get it to go reverse - Any ideas?? Please.
> btw I am using a huge hi-tec hs-805bb servo with a basic stamp2 and
a
> BOE and powering it with a radio shack 7.5v 2000ma battery which is
> what was recommended - This power is going directly into th eboard
> without using a harness but it seems to be fine as it is regulated
> before getting to the stamp.
> Thanks
>
> --- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> > Ever consider the following code, (slightly revised)..
> >
> >
> > hth
> >
> > Leroy
> >
> > Main:
> >
> > forward:
> >
> > for pulse_count = 125 to 250
> >
> > pulsout 14, pulse_count
> >
> > pause 20
> >
> > next
> >
> > goto main
> >
> > Rodent wrote:
>Also before modifying the servo (cuttingo ut the little plastic
>stopper on the gear) then it works fine as an unmodified servo (ie.
>forward and backward) Once it is modified I cannot get it to go
>continuously forward and backward.
Perhaps you need to center the pot or replace it with a fixed value equal
to it's centered resistance?
Jim H
position is determined by the pulse width of the signal sent to it. It
needs to see this signal every 20 or so milliseconds to hold position.
To move to a different position, it needs a new pulse width. From 0
degrees to about 270 degrees of rotation on the servo requires a pulse
width of approximately 125 ms to 250 MS. See the program below to back
it up:
main:
'reverse
for pulse_count = 125 to 250 step -1
pulsout 14, pulse_count
pause 20
next
goto main
hth
leroy
mafox67 wrote:
>
> Taht works great for going forward and I can adjust the pause and
> make it go faster and slower - Problem is that I changed all of th
> evariables and cannot get it to go reverse - Any ideas?? Please.
> btw I am using a huge hi-tec hs-805bb servo with a basic stamp2 and a
> BOE and powering it with a radio shack 7.5v 2000ma battery which is
> what was recommended - This power is going directly into th eboard
> without using a harness but it seems to be fine as it is regulated
> before getting to the stamp.
> Thanks
>
> --- In basicstamps@y..., Leroy Hall <leroy@f...> wrote:
> > Ever consider the following code, (slightly revised)..
> >
> >
> > hth
> >
> > Leroy
> >
> > Main:
> >
> > forward:
> >
> > for pulse_count = 125 to 250
> >
> > pulsout 14, pulse_count
> >
> > pause 20
> >
> > next
> >
> > goto main
> >
> > Rodent wrote:
>
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used fixed resistors instead of the pot that one is open.
*******
> One more thing - I am using a modified servo - (all I did was dremmel
> out the plastic stopper on the gear- I also have an unmodified one an
> dwhen I use the code below it works fine (forward and backward)