Can you define “more”?
What version of the programmer are you using?
The knee is set to +/- 90° on our bot. While not correct for a humanoid, it is useful to make the robot do some cool things.
Is the default range of motion for the HS-422 90 degrees also? I checked the shop, hitec and servocity and none of them say.
All analog servos are 180 except for some special feature ones like sail winch etc. All digital servos are 90 except the 5995 which is 180.
Ohh, 422 is analog? What servos does your BRAT use?
I think I see what is happening here. The servo range is defined as working with pulse widths from 900 to 2100 and as I understand it 90 degrees is from 1000 to 2000. This would give about 90 x 1.2 = 108 degrees of rotation. I just checked the range of motion of my (BRAT’s) left knee with a protractor and it came out to about 130 degrees from one extreme to the other.
This may in fact be one of my problems with the Sequencer since it defines this range of motion as 180 degrees. Is that right?
Harry
Analog servos have a range of ~180° that is achievable by sending pulses in the neighborhood of 600uS to 2400uS. Each servo will be slightly different.
An off the shelf digital servo has a range of ~90° that is achieved with a pulse length of 900uS to 2100uS. Anything outside this range will be ignored. If you adjust the range as shown in my tutorial with the digital servo programmer you will have ~180° but the pulses will still be 900uS to 2100uS.
The power of the Sequencer is, all movements are stored as angles, not pulse lengths. The config screen allows you to calibrate the software to your servos. This process involves moving the servo to the min and max position it can move to, and assigning an angle to those limits. So it is not important what pulse length your servo requires to reach a certain angle. But if you want to use other peoples projects your servos will need to have the same range as theirs. In other words, people can share projects without being concerned that they need to use the same type of servos that the original person used. Because the calibration allows you to reverse the servo response you can even use Futaba (CCW with larger pulses) instead of Hitec (CW with larger pulses).
The new Sequencer update (should be available today) will also allow you to assign the 0° pulse value as well. This makes it much easier to do the calibration.
BTW I have a program that works on the Atom Pro that reprograms a 5645 servo to the 180° range. I have to create a tutorial to tell people how to do it. Ug! so much work… so little time!
Thanks for the explanation, Jim. I’ll reset the range of motion to 180 deg. based on your tutorial.
Given what you’ve stated, I’m now puzzled as to why my knee servo has 130 deg rotation with factory default settings.
Harry
Hello Harry,
Everything I said above was true except… (I just sat down and tested some things!) The pulses accepted by an off the shelf digital servo is more than I thought. They may have changed it, or I may have misunderstood something back when I was first working with the programmer. On my test servo I was able to get the range you mentioned. On mine it was 748uS min and 2238uS max. Going just 2uS more in either direction resulted in the servo ignoring the pulses. I know Hitec just changed the programmers firmware. I’m not a fanatic enough to try and figure out if this is one of the things they changed.
Looks like I may need to change my Atom Pro servo programmer to a little less expansion. I mean why double it if the servo can see a 748uS to 2238uS range. To prevent any servos from not responding to an out of bounds pulse perhaps a 755uS to 2230uS range would be more conservative. Just need to alter the servos firmware make sure 180° range is achievable.
So mystery solved. 
Sorry for the misinformation. Blaaa
Ahh, so that’s why I never needed the programmer with my 5645’s.
Of course, knowing this doesn’t actually help anything, but it’s always nice to have closure.
^.^
'ello, wats all this then with the new tutorial? for the SSC-32 and Bot Board 
sure, do it after i get it working
pout
Dearest friend, you have nothing to whine about.
I on the other hand certaintly have great whining privelages.
Why?
Because Jim/Beth/James (take your pick) had the gaul to go and create a WiPort tutorial after I fried mine.
Yea, Nick has greater whining rights than you. Ouch, that must hurt. Well, both tutorials are writen and I havent even ordered my BRAT 
So im good
Wonder what is the next tutorial.
eh…good point
I’m thinking of building a BRAT using both a SSC-32 and a BASIC Atom (in a Bot Board). Would it be better to power everything off the 1600mAh Battery Pack, or should I power the logic seperately via a 9V battery?
In either case, what would the typical run time be?
Hey,
Typical run time is about 1hour to 1.5hours +/- some error. Using a 9V battery for logic would be a waste of weight as I understand. You add weight to the robot which it does not need. Logic does not really need much battery. It is the servos that eat up the battery.
If you have a 9v around the house then just try it. If it doesnt change the weight much and gives you some extra time, then go for it.
-robodude666
1 hour , or even close to it, sounds pretty impressive. I wasn’t sure where I’d mount a 9-volt anyway, although I don’t have my own BRAT yet to look at.
If I do test a 9-volt in the future, I’ll post my results.
I agree and disagree.
While I’m testing/programming the biped, I use a 9V.
This is so that when the servos overdraw the batteries, the SSC-32 will have a seperate supply, so they won’t reset.
When I’m just playing around with it and making it fight my cat, I ditch the 9V, since I don’t feel like toting around the extra weight.
HAZA! I am now a proud owner of a box pending in IL =D
orders@ lynxmotion.com Your Lynxmotion Order Number is: ***** Mon Aug 14, 2006 5k
=D I just ordered my brat. I didn’t order it as a kit though. I ordered it by parts because I am going to be using 5645s instead of the stock servos. This way I don’t need to pay for 90$ of servos I won’t use later on.
w00t. Lets see how long it takes to come to NY. If it takes 2 days to go to canada, don’t think it will take long to get here.
Time for the happiness dance:
boggies
yeah, I would have loved to do the same for the servos because I dont think I will use 422’s but I didn’t hgave enought money 
.
Sam
Poopy! I forgot to order a cable to connect the ssc to abb.
Chunga said the SSC-32 comes with a cable to connect it to the ABB. Is that true? Also, does the SSC-32 come with the shortbar jumpers? If so, how many? More than needed?