New to servos, need some help on deciding which to buy

Hello,

So first off, I would like to say I decided to get into servos just yesterday and I learned quickly that I haven't learned anything about them at all. So I did some research and have learned a few things so I still consider myself a n00b at servos. Here is my ambition: http://www.youtube.com/watch?v=pXMnbNoccgA&feature=relmfu

I want to make one of those robots and i'm just having trouble deciding on which servos to get. Do I need full rotation? Do I need analog or digital servos? How do I decide which one to get if they have a line of servos?

Bonus information: I am going to use an atmega328p to control the whole d ealio, i'm also using 2 TLC5940 drivers to control the servos. The TLC5940s are connected through digital pins of the microcontroller.

Can anybody help out?

You definitely don't want continuous rotation.

Since you will be needing 18 servos (three per leg) you should probably start with some cheap ($10) ones.

What kind would I need? Digital or analog?

Also, will cheap $10 be able to work like those in the video? I would be willing to go up to $14 dollars each.

I do have a quick question.

The TLC5940 operates soley on digital pins, although it has PWM outputs. Does that mean that I can use analog servos with it? Or will I need digital?

funkyguy4000: What kind would I need? Digital or analog?

Also, will cheap $10 be able to work like those in the video? I would be willing to go up to $14 dollars each.

All radio control servos are 'digital' in that they are controlled by sending them a PWM (PPM really) pulse to command them to a specific position and stop. So called Digital servos are just more advanced (and expensive) servos that with special interfacing hardware and PC software can be 'tuned' and set-up for specific responses. You only need the the standard cheap 'analog' servos to get started learning how to use and control them with your arduino. Later once you have more experience with using servos you may possibly pick a project that needs a more specific servo feature like more torque, larger travel, etc. And yes stay away from so called modified 'continuous' travel servos, you will not be getting what you think you will be getting.

Lefty

Okay so you are saying that I would use digital servos.

I just found out that the people over at HSD use the Hitec Zebra ZS S2113 Std Servo which are analog, and the issue is that they aren’t being made anymore, Is there a comperable digital servo?

Also if I got analog servos, but still wanted to use the TLC5940 to control them (which outputs 16channels of PWM signals), would I need to do this? http://dev.emcelettronica.com/how-to-use-pwm-to-generate-analog-or-analogue-voltage-digital-circuits-part-2

Instead of asking in this forum, you should first study proven multileg designs that are known to work with particular servos. The below forum has multileg discussions and the bottom site sells proven designs. Best to see what works instead of guessing. The length of the legs will have a lot to do with what strength servos will be needed. The bots in your video have fairly short legs, which may allow the use of inexpensive servos.

http://www.lynxmotion.net/viewforum.php?f=8 http://www.lynxmotion.com/