okidey
Hi!
My name is Kristian. I have recently ordered the EZ-B Board here, and am excited to consider myself a new EZ-B owner!
Well, almost. I am now awaiting all the items to be delivered, and ofourse have been thinking about various things to build. Naturally I have my questions also..
Together with the EZ-B board I have ordered a total of 18 Heavy duty Servo's, 1 Ultrasonic ping sensor, and 1 Mini servo to sweep the Ultrasonic sensor. I am thinking of building a Hexapod. I intend to use all 18 heavy duty servo's for the legs, 6 legs each having 3 servo's. Similar to a robot I've seen from Lynxmotion, namely the 'Phoenix' Hexapod version. So I need to consider a proper power source. If anyone could give me some suggestions, I would very much appreciate it. I was considering using a set of either 6 or 8 AA recharbeable batteries of 2700mah, would that work?
Also..I am assuming there will be no Bluetooth dongle included so I will have to purhase one here in Holland. An Asus bluetooth stick 2.1 EDR USB-BT211 seems like an interesting option, allthough I have no idea as to wether it would be compatible with the EZ-B. What do you guy's think?
And one other thing.. I was wondering as to wether someone else might have built a similar concept of a Hexapod robot, and wether or not someone here has any experiences and/or useful information regarding the coding for movement and balancing of such a robot.
Any information regarding these 3 questions would be greatly appreciated.
Further more.. I have to admit that I am an absolute beginner when it comes to coding, robotics and electronics. Right now my knoledge and experience regarding all these aspects is very, very limited. I am however eager to learn, and like to consider myself smart enough to be ABLE to learn. But if I seem slow, please bare with me.
*EDIT
About the battery question, I have read a little further in the forums and have instead decided to go for a Li-Ion 7.4v 2600mah battery pack. I'm guessing that should do the trick.
Thanks, I am looking forward to building my own EZ-B!
Greets, Kristian.
With 18 heavy duty servos, you might wind up needing to supply them with alternate power so as not to brown out the board. Try with the single pack, but if you get connections dropping, there are instructions in recent threads about alternate power, and DJ will soon have an alternate power board to make it easier.
For hexepod motion, I think you could use the new relative servo motion control to do very smooth coordination of the legs.
Alan
yeah if you have more than 4 servos a different power supply will be a must for sure
Thanks for your replies!
Just to understand correctly, if I use the single pack and connections start dropping out, is that a sign of the board burning out?
If I want to make sure I get it right the 1st time, would using 2 Li-Ion 7.4v 2600mah packs, 1 for the board and another for the servo's be my best bet?
Kristian.
Not burning out, browning out. Too much power demand.
@okidey yes two batterys is better to prevent a low current availability for your board. they call this " BROWNING OUT" the board turns off and doesnt function. 7.2 volts may be too much for those servos so go buy a DC to DC regulated power supply, they are usually adjustable from 12v to 6v or lower.
Alright, oops. I missread that.
So I'll just buy 2 packs and try with 1 first, then wait for that alternate power board.
About that Asus bluetooth stick 2.1 EDR USB-BT211. Does anyone have experiences using this? Would this be suitable for the EZ-B?
@ jstarne1 I have ordered the bench table power supply sold here on the website, would that be alright too? or would that be too much? Lets say these servo's 6v. i would have to hook them up directly onto a 6v dc powersource? and lets say a 7v dc powersource for the board?
Thanks for your replies.
Kristian.
You only want a max of 6v directly to the servos. You can either use a 7.2 pack and a voltage regulator (it will get warm, but you'll have plenty of amps for the servos) or you might be able to find a 6v power source with good amperage.
Virtually any BT stick should work. They pretty much all support serial over BT.
Alan
Welcome!
Alot of great folks here with some great knowledge. Your project sounds absolutely sick..can't wait to see it develop!
v/r
kevin
Hey Jastarne,
when you stated 4 servos needs alternate power supply......you mean the 4 high torque servos right?
how many regular servos can you run on 1 power supply?
@TheTechGuru
Thanks Alan, I think I understand now. The board regulates any powersource to 5v, but the heavy duty servo's prefer 6v. Espescially with so many servo's it can cause a 'brown out' in the board. So I need at least one 6v DC power source to either feed both the board and servo's but individually, or add another seperate 4v - 14v DC power source for the board.
So what remains is to ensure enough amps, espescially for the servo's. If I were to get my hands on five 1.2v, 13000 mah Nimh rechargeable battery cells and line them up to make 6v, would I then have a decent powersource to at least feed the servo's, if not both the servo's AND board?
This is a datasheet of those cells in .pdf format http://www.produktinfo.conrad.com/datenblaetter/250000-274999/255048-da-01-en-EMMERICH_NIMH_AKKU_F_13000_MAH_FT_1Z.pdf
@kkeast
Thanks!
I'm looking forward to seeing it develope myself too. As I've said, I have little to no experience in robotics, and I will no doubtidly come here often for help and information. I will have to begin with constructing the body or frame for this Hexapod, I was thinking of using black Plexiglass as material.
I do not have a whole lot of fancy tools available to me but I have the basics and nescesities like a Dremmel and the various bits, gluegun, solder iron etc. So that should not be a problem. I have a basic practical understanding of electronics, putting it together should not be a problem. However, I have NO experience in the software or programing of such things.
This EZ-Robot board from Dj Sures, with the ARC software package will prove to be a good introduction and foundation for me to learn about robotics. Also reading around in the forum offers a lot of information and support and friendly members to learn from. This will be fun!
Kristian.
It's always best to have a different power source / battery for your electronic control board. The only exception is when you do a very large bot with large array of batteries. As far as battery type lithium ion or larger 4ah or higher sealed lead acids maintains voltage. For lighter small projects lithium ion are the way to go for sure. My favorite brand is turnigy and hobbyking.com is a great place to get batteries cheap
For the servos, 6v is the max, not the requirement. It is really the amps that are important to make sure they all have enough juice to run, particularly with a hexapod where a bunch will be moving all at the same time.
I am the first to admit that I am still learning this stuff. It has been 31 years since I last did an electronics project in high school. But I have been reading posts here for the past couple of months and learned a tremendous amount from the other posters.
There is a current thread about HD Servos with a lot of good data in it.
Alan
Thank you for your replies.
Your replies have given me an idea of what to do. I have decided to use 5 rechargeable Nimh cells 1.2v of 13000mah for the servo's. And i have ordered a bluetooth usb. Now I will have to wait for everything to be delivered, I'm looking forward to building!
Greets, Kristian.
Hej Hallo,
Ik zie nu pas dat je ook uit nederland komt.
Ik heb net mn 3e boardje binnen. Heb al aardig wat in elkaar gezet met de ez-b
Ben nu met een Omnibot 2000 bezig. Hij heeft nu 10 servo's
Zelf gebruik ik een 7.4 volt 4a en heb het spoor tussen de + weg gehaald en de accu daarop gezet. de ez-b heeft zijn eigen voeding door de bijgeleverde 5 pack batterij houder.
Hoop dat je hier iets mee kan
Hey gaaf!
Ja daar heb ik zeker wel wat aan, ik zat al te denken hoe ik al die draadjes van 18 servo's op een andere battery ging aansluiten haha!
Al je 3e? Jij hebt al aardig wat ervaring opgedaan dan met dit spul? Ik zelf ben echt helemaal nieuw. Ik kan best leuke dingen in elkaar zetten maar wat betreft programeren and dergelijke zal nog een avontuur worden voor mij.
Dank je voor je antwoord, daar heb ik echt een boel aan en dat zal ik zeer zeker ook met die van mij doen.
Groetjes, Kristian.