go_away

Author Topic: digital or analog servos?  (Read 2448 times)

0 Members and 1 Guest are viewing this topic.

Offline richard mackieTopic starter

  • Jr. Member
  • **
  • Posts: 24
  • Helpful? 0
digital or analog servos?
« on: November 26, 2007, 10:55:20 PM »
hey everyone im new to the forum Im a freshman in college and well the end of the semester is near so i will be using my month off to hopefully build my first robot, nothing too complicated and simliar to the 50 dollar robot.


My question is should I go with digital or analog servos? I have never worked with either of them and have read that digital use up batteries faster and are more expensive but also have a better torque and precision. Analog are just cheaper and use the batteries up slower. I want something with power that i can use in the future projects such as this
http://homepage.mac.com/sigfpe/Robotics/equibot.html
digital are most expensive but are they worth the investment?
« Last Edit: November 27, 2007, 01:18:42 PM by richard mackie »

Offline Robotboy86

  • Robot Overlord
  • ****
  • Posts: 139
  • Helpful? 0
Re: digital or analog servos?
« Reply #1 on: November 27, 2007, 01:33:29 PM »
Short answer:

No.   Digital servo's just roll a few different systems into a nice package for you..  a good deal of servo usage doesn't need to be that percise. 

Long answer:

Yes!  They are indeed worth the money if you need all of there features..  for example I am currently working on a hexapod.  My hope?  That it can run in the end.  Yes, like an animal loping across the plain kind of deal.. but it must first learn to stand, then crawl, then walk, then move, balance, and then to run.  So for now, I am buying a few 1/4 size(bigger then micro) servo's and the robot will only have 1 dof per leg.  The leg joint itself.  Where it meets the base and all.  I will be building from there and moving into other fields(such as balance) as I need to..   but not until far into the future will I really even want digital servo's(if at all). For now, analogs are great.. and even if I end up not using them on this one, I will on another.

Offline richard mackieTopic starter

  • Jr. Member
  • **
  • Posts: 24
  • Helpful? 0
Re: digital or analog servos?
« Reply #2 on: November 27, 2007, 04:53:25 PM »
thanks ill just stick with the analogs for now

Offline Admin

  • Administrator
  • Supreme Robot
  • *****
  • Posts: 11,658
  • Helpful? 169
    • Society of Robots
Re: digital or analog servos?
« Reply #3 on: November 29, 2007, 12:08:53 PM »
My advice is get the servos that match the specs of your robot.

Don't spend extra for features you don't need :P

Although, you may want to get better servos on the assumption you will need them in future robots you build . . .

Offline Fredrik Andersson

  • Robot Overlord
  • ****
  • Posts: 216
  • Helpful? 0
Re: digital or analog servos?
« Reply #4 on: November 30, 2007, 12:13:39 PM »
Even if one for sure will need better servos in the future it's not worth buying them now if you won't need their full capability yet. The prices on servos are falling really fast, so you will probably get off cheaper if you buy them when you really need them.
Current project: Pirrh - Portable Intelligent Round Rolling Hexapod

Offline richard mackieTopic starter

  • Jr. Member
  • **
  • Posts: 24
  • Helpful? 0
Re: digital or analog servos?
« Reply #5 on: December 01, 2007, 01:54:30 AM »
Thanks everyone for your advice. I ended up ordering my servos before I read the last 2 replies, but I think I'll be happy with the ones I ordered. I went with  2 HS-422 already modified for continuous rotation and no I did not buy them from servo city with the 20 dollar modification fee. I got them through Lynxmotion at no additional cost for the continuous rotation, and to save on future shipping I went ahead and ordered a standard HS-422 for the IR scanner(its the cheapest servo they have). Lynxmotion also had a 13 dollar battery that met specs. So everything is in the mail and I wont be able to start until the 13th or so(finals start next week  :().

 


Get Your Ad Here