servo and crystal frequencys qeustions

[that guy]

ok im VERY new to robotics and ive been wondering- do normal servos go back and forth or do they keep spinning continuously.
and on an rc car called a nikko mantis where can i see the crystal frequency?
what sort of servo can i use for a biped and are there any good biped tuts out there?
thanks if you answer.

[Joker94]

1)Servos turn back and forward, but when un modifyed it is only about 180 degrees of rotation or less. Once modifyed it can still go back and forward but can also go in one direction continuously.

http://www.societyofrobots.com/actuators_modifyservo.shtml

2)For finding the crystal frequency look at the circuit boarad and find the crystal and see what is written on there and if you don't understand it google it or post it here.
What you are looking for=

3)For a biped, depending on the size you will probably want a miniture witha weight of 9 grams. Or a smaller servo like a miniture servo, i recommend the 9g servo as depending on what you make it out of you may need the extra power/torque.

As for a tutorial  i found nothing about the mechanical side of things, but i found a software related tut and an old thread that may be a good read.

http://www.societyofrobots.com/robotforum/index.php?topic=4778.0
http://www.societyofrobots.com/sor_biped_engine.shtml

[ArcMan]

An R/C crystal typically has a pull tab wrapped around it with a number on it. (e.g. - 70).
You can find the crystal's frequency by looking it up in a table like this one:
http://www.ultimaterc.com/misc/rc-radio-frequencies.php

Although you really don't need to care.  As long as the transmitter crystal number matches the receiver crystal number, you're good to go.

[Razor Concepts]

Considering its a nikko, there wont be any externally visible crystal but it is most likely 27 or 49 mhz.

[that guy]

it does say its 27mhz so would any 27 mhz remote work?

[Razor Concepts]

Probably not, different 27mhz systems will have different communication systems. Your best bet is to get another 27mhz controller from Nikko since each brand usually sticks to its own little system.

[Admin]

are there any good biped tuts out there?

There *will* be. I'm working on a biped right now

Keep an eye on the SoR Youtube account in about a month or two for videos.

[that guy]

great hope it helps me!

[that guy]

ok ive seen nomal servos and continual servos on wbsites but alot of what i see is digital servos-whats the difference between digital and continual or normal?

[Admin]

did you google it? or read the servo tutorial on SoR yet?

[that guy]

oops never saw that