Hi everyone.<o:p></o:p>I am Giovanni Izar.<o:p></o:p>I am brand new to robotics and this will be my first attempt at making one. I will call it “The G_Bot.<o:p></o:p>I have skimmed through the rules and intend to follow them but forgive me if I stray and correct me when I screw up.<o:p></o:p>I have all my parts but I am not sure if they are all correct so if anyone can spot something wrong or out of place please let me know.<o:p></o:p>When I got my Picaxe 28x1 it came with a 3 battery holder. (I got myself a 4 battery holder from RadioShack (The Scource in Canada). This immediately got me thinking voltages and I have concern about whether the motors I have will hold the voltage I will be feeding them.I guess they will just go faster butI will be watching for smoke none the less.<o:p></o:p>The servo I got is a continuous rotation servo. Will this be ok?<o:p></o:p>I like the look of the Tamiya gearbox i found and decided to use it instead of the G9 motors in the Start here tutorial. I may get the G9’s later.<o:p></o:p>The sensor I got is listed as a GP2D12 and not GP2D120 as noted in the tutorial. I hope it is the same thing<o:p></o:p>I forgot to order the servo chip so I am going with the resistor instead.<o:p></o:p>I got all my parts 2 days ago but could not get myself to start until I had read enough here, photographed and documented everything. I am a CNC Programmer Machinist and will probably make my own wheels.<o:p></o:p>I am now ready to make a robot and hope to get some input from some of you. Knowing me this Robot will look nothing like I expect it to look right now and will probably take much much longer to build than most of you because I am never happy with what I produce the first time round. For instance I will probably turn out 6 pairs of wheels before I am happy with it.<o:p></o:p>My Photos are at www.izars.com/robo <o:p></o:p>I own the domain and am prepared to dedicate it to LMR if that is a good Idea <o:p></o:p>Whish me luck.<o:p></o:p>
Runs around sees things and avoids them and perhaps makes some robot noises via a speaker
Actuators / output devices: servo, IR Sensor, Tamiya Gearbox 114.7:1
Hey g_code, I suspected you might be a ‘CNC person’ judging by your name =) I’ve used the same Tamiya gearbox at 6V before with no problems. You will however need some kind of motor driver - at the moment you have nothing capable of handling the current needed to control the motors.
You keep referring to “the tutorial”. Do you mean the “start here” tutorial?
The GP2D12 is NOT the same as a GP2D120. The GP2D120 has a much shorter range than the GP2D12 (4-30cm vs. 10-80cm), but is more precise within that range.
As TeleFox said you need something to drive your motors capable of providing the current your motors draw. A resistor (as you mentioned?) isn’t gonna do it.
A servo for continuos rotation has been modified to act like a dc motor. You no longer control the ANGLE of the servo but rather the SPEED and DIRECTION, which isn’t very suitable for mounting a sensor on top of it.
PS: When fritsl asked you to read the rules he probably meant this: “Do not post as a robot if you have not built anything”. Your entry would be more suitable as a forum topic or a blog entry
I noticed you mentioned getting a 4 battery holder (I assume that is 4xAA batteries), and your concern about smoking your motors. Maybe you already know, but the Picaxe can support two voltage supplies (V1 and V2).
V1 is for your logic levels and powering the ICs. You want to use 4.5V or 5V for V1. The Picaxe chip won’t want anything more than 5V, so be sure you don’t hook up 4 AA batteries to your Picaxe board as V1. Some sensors want no more the 5V. Check your specifications before hooking stuff up so you don’t smoke it.
V2 is for powering your output devices (motors, servos, etc.) 6V would be fine for many motors and servos. Typically servos are rated at 6V max.
There’s a nice tutorial on the Picaxe board by Fritsl that describes all the pins including power and ground. I think there’s a link to it from the Start here post.
The dual Tamiya gear motors are nice. Take special care in assembling them and be sure to add some gear grease. These motors are a bit loud, but they work well enough.
I did but I think I am lisdexic and may not understand it all;-)
Could it be that you want the LMR logo there (It is there now take a look
Could it be that I should not use my own Domain?
Or is it because My Robot is not yet complete? I did ask about it in the shout out and was told that I had to have started it. I actually did start it last night (Assempled the controler and soldered wires to it.
Please let me know.
As I said my domain is available for any kind of use as I just use it for email addresses and My resume.
I DONT intend to use it for Spam or advertising.
LMR Is my latest addiction and wish to be an on going part of it.
The GP2D12: Will it work or do i need to rush out and get the right one right away?
Motor Driver: I do have the driver chip I just forgot to mention it in my post. (I will whip myself 7 times before going to bed tonight for forgetting)
The Continuous servo: Again, Will it work or do I have to rush out and buy the right one. If you mean its going to be more difficult to program but will still work I would be happy with that.
If I have to go out and find the right parts I will whip myself from now untill I get the right parts.
GP2D12: It works fine. It just depends on the RANGE you want detect. I read that the two sensors have the same elctronics and just have different lenses (therefore range). I prefer and use the GP2D12 because it has longer range. This mapping test I made is based on a GP2D12.
Continuous servo: If you plan to mount a sensor on i, it’s no good. You have no way of telling in which angle it’s pointing (see my former post). So yeah I would get a NORMAL servo for that job.
Motor driver: What chip did you get? Make sure that it can supply the current needed by your motors.
It was merely because your picture was a picture of a third party product. And the rules state that you need to have “something to show” before posting as a robot. A third party product case is not that something, that’s all.
The reason for all this is is just that we woudl get a lot of “i intend to build this”, posted as robots if the rule was not there… and that would make a sad collection of robots, these things should be in the blogs.
All cool, no prob, have fun, and thanks again for joining in
Did a quick google check. And actually it seems that your motors are a bit too current hungry for your H-bridge chip. The L293D supplies 600mA steadily and 1200mA at peak, while the FA-130 draws 660mA and 2200 at peaks. See here:
Perhaps this could be solved simply by keeping the dutycycle of the PWM signal appropriately low?! But frankly this is where I hope someone with more knowledge of these things will jump in and say something clever. I’m also quite new to this electricity mumbo jumbo and I too would be interested in the download you mentioned, if such a thing existed
However unless your goal is to smoke your L293D chip there are a few things you could do to improve your setup:
Mainly add some capacitor to you setup. Ufortunately there isn’t one golden way to do this but many and I can’t tell you which one is the better. But I can provide you with with a few links:
Just an idea I am not plugging anyone but I use Parallx stuff when I need to. Their stuff may be a bit pricy, but they have the best forum for help on THEIR quality products. They are tied in with alot of schools for training in the USA. The "What is a Microcontroller" or "Boe Bot" kits offer a well orginised platform for learning both electronics and basic stamp programming. You can even download the books for free on their site.Their forums are the best I have found anywhere for help and have an engineering staff on board. I cheat and hack alot of my programs from there. You are in Canada so may not be as expensive as other places and there is always ebay for the deals. I should also mention using erector stuff for building robot bodys cheap. They are easy to build up and tear down and very cheap on ebay. Most my robots have a breadboard built on for easy wiring like many processor boards now have.
