My robot Idea

[gamefreak]

Alight this summer i thought that i would try to create a non-kit robot, so i was working with Autodesk Inventor and so far i have a base with wheels(no casters yet, still looking for one i like) I'm trying to make a tricycle like robot with the front/back wheel(haven't decided which direction it goes yet) act as the steering wheel.

the grayish block on top is my Professional Development board i have, it includes led numerical displays, audio, DIP switches, Press Buttons, an LCD Screen, and a breadboard(i haven't figured out what the other things are/do)

the base is an 11 inch by 12 inch and i plan to build it with HDPE, it is about .5 inches thick and the side brackets are approximately .25 inches( is that small enough to bend like that?)
I have a Miter Box so i should be able to build the basic frame, i have a hack saw and some drills so i think i should be able to cut it all.

If anyone can think of some modifications please post them and i'll consider and revise my model for my final production.

Im still working on the sensors, but i think that this will be a simple photovore for now

so here are the rendered pics of my model
edit: fixed some stupid mistakes, and added wiring and batteries

[ed1380]

looks awesome.
are you gonna make and sell them or just one for yourself?

[gamefreak]

lol, that is the idea form, now if i get around to actually buying the parts.......

also, i'll have to buy a perforated board and put use the 30$ stamp tutorial so i can save money....

lol, its probably just gonna wander around my house until it dies a horrible death by either dog attack, cat attack, or the stairs making a fool out of it. As soon as i can draw a good caster then i can finalize my design, im thinking about an arm but that might be to confusing for me,

[Admin]

i plan to build it with HDPE, it is about .5 inches thick

For a base that size, I always use .25" thickness and its very rigid and strong. I would go thinner (perhaps .125"), but I like having room to screw stuff in to the base.


You might have trouble making the servo mounting brackets (bending, and cutting a servo shaped square into it, while keeping the holes aligned). I remember having trouble a few years ago when I tried that method for the first time. It came out really hacked up and ugly. This also goes for the square hole for your middle servo . . . Servo mounts that usually come with servos work best for me.

[gamefreak]

well i still want to try, so what thickness should i use for the servo brackets for bending? the 8th inch or should i go smaller still?

[Admin]

Well it depends a lot on your expected forces, weight, etc.

For high forces I'd probably use 1/8th to 1/16th inch aluminum for the brackets.

For low forces I'd probably use double sided sticky tape.

(assuming I didnt have the rubber servo mounts)

[megaman935]

For low forces I'd probably use double sided sticky tape.

double sided sticky tape will one day rule the world- it can be used in so many different ways..

[gamefreak]

alright, i guess i can use the bracket, also, once i get this giant prototype working i can probably make it a lot smaller with a perforated board, the reason its a 11X12 inch is because the development board is a 5X10 inch.

Also, any other ideas on what to add to this design?

for batteries i'll probably take two: http://www.onlybatterypacks.com/showitem.asp?ItemID=10313.2 batteries
or two of: http://www.onlybatterypacks.com/showitem.asp?ItemID=10403.7

i'll get 2800 mah which should be enough to run for a good amount of time

[ed1380]

$16 plus shipping is too much.
wasn't there someplace you can get 3 for $21?

[gamefreak]

16$!?!?!?!

lol, i should probably read that kind of stuff, anyways those are just sample batteries, i was planning to shop around to find them for cheaper, they were just the first thing that popped up on google.

after i get better at robotics i might add an arm to it so it can maybe fetch the morning newspaper, or get me my Dr. Pepper

[Admin]

Dont get NiCad, its outdated technology . . . I recommend NiMH these days . . .

NiCad is only for really high current stuff, for like battlebots and such . . .

[gamefreak]

alright, in my model pics i added in two battery packs that are the 6 volt NiMH  1400 MaH, i alos added some crude wiring for clarity, maybe later i'll actually make the bread board and wire it out on autodesk inventor (might be more trouble then its worth)

so anyone got ideas on what to add?

[maverick monk]

Dont get NiCad, its outdated technology . . . I recommend NiMH these days . . .

NiCad is only for really high current stuff, for like battlebots and such . . .

anymore nimh dose not mean low current, i have 6 cell 3600mah batteries and those are considered low end, they go up to 4600 at least, and thats just sub c cells. many have a discharge rate of 10c+ also... nimh has gone the way of the dinosaur. ( actualy, the new 'in" thinjg is li-p0, many lipo packs the size of a 6cell sub c pack are 8000mah, and discharge rates of 20c

[Admin]

They may be outdated, but I dont trust beginners with Li-po

This is why:
http://www.societyofrobots.com/robotforum/index.php?topic=1063.0

Better to make your mistakes on the cheaper safer battery types.

I have a bunch of 5 year old NiMH batteries that I still use on all my newest robots . . . And NiMH are much better than they used to be 5 years ago.

[maverick monk]

as long as there not idiots its not a problem, just read the directions and get a voltage cut off meter. dont be a dumbass and youl be fine, i used li-ions when i was a noob and they worked great, i took care of them and they lasted untill i sond the car

[Ai-bot]

They do have a circuit that auto cut of for you when the Li-po drop to a certain voltage.
I can:t remember where I saw it, but I think the price was $25.
It is not a bad idea in case you forget to check the voltage.

I kill one of my Li-po...because I lost track of voltage while I was doing something.
It was a few years ago, so LI-po was very expensive.
I think I paid $250 for the battery back then.

Never going to make the same mistake again.

[gamefreak]

since i don't feel like spending 200 dollars for my robot then having it spontaneously explode in a fiery ball of doom, i think i'll stick to nimh, much safer.