Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: creedcradle on October 20, 2007, 04:21:22 AM

Title: CAD of new Robot (need help)
Post by: creedcradle on October 20, 2007, 04:21:22 AM
This is just the CAD of the chassis, simple enough...Target Date of accomplishment will be on December..

Later i will add: the RF receiver, sensor for for obstacle avoidance, ground contact sensor, and temperature sensor.. and if my pocket would be kind.. i will add a camera on this robot..

TOp view:
(http://i205.photobucket.com/albums/bb200/nauuhaw/top.jpg)

Trimetric view:
(http://i205.photobucket.com/albums/bb200/nauuhaw/trimetric.jpg)

Isometric view:
(http://i205.photobucket.com/albums/bb200/nauuhaw/isometric.jpg)

Dynamic view:
(http://i205.photobucket.com/albums/bb200/nauuhaw/dynview.jpg)


Soon i will post the schematic but i will post no source codes..  i will do this robot without any microcontroller involved...
Title: Re: CAD of new Robot
Post by: Steve Joblin on October 20, 2007, 07:43:44 AM
why no microcontroller?  Is it just for the "challange" factor?

Your CAD's are nice, but one thing that always frustrates me with these is that there are no measurements... how big/small will it be?
Title: Re: CAD of new Robot
Post by: creedcradle on October 20, 2007, 03:42:49 PM
why no microcontroller?  Is it just for the "challange" factor?

yes. i cant find a reason why use microcontroller when the tasks of the bot are simple.


Your CAD's are nice, but one thing that always frustrates me with these is that there are no measurements... how big/small will it be?

I have the complete measurements for this CAD bot. i will post it later... im trying to figure out how to shrink the file. the entire sheet would occupy a big space..
Title: Re: CAD of new Robot
Post by: paulstreats on October 20, 2007, 04:32:33 PM
how will your robot react with the temperature sensor?. Will it go towards hot/cold spots.
Title: Re: CAD of new Robot
Post by: creedcradle on October 20, 2007, 05:08:03 PM
@paulstreats

my bot should move away from hot spots. of course, the wheels will melt if the bot would go into the hot spot.. :D

im still trying to evaluate the melting point of the materials that i will be using..
Title: Re: CAD of new Robot
Post by: creedcradle on October 21, 2007, 03:33:11 AM
Here is the dimensions of the bot

(http://i205.photobucket.com/albums/bb200/nauuhaw/CADbot.jpg)


I guess the file is really big and the dimensions arent visible. need to download to view the dimensions

http://i205.photobucket.com/albums/bb200/nauuhaw/CADbot.jpg
Title: Re: CAD of new Robot
Post by: Admin on October 21, 2007, 09:34:46 AM
just an FYI, images can be uploaded to this forum (if you ever want to bypass photobucket) ;D
Title: Re: CAD of new Robot
Post by: creedcradle on October 28, 2007, 01:56:32 AM
here is the final CAD of the bot

(http://i205.photobucket.com/albums/bb200/nauuhaw/cambot.jpg)

Admin
dunk
jonhylands
h3ro

and all others in SoR who knows what i don't know.. i need help..

Questions:
1. how can i build a temperature sensor that will be able to measure temp  greater than 3 meters from the robot. as much as possible i don't want to use a module or anything .. i want it to be totally home built from basic discrete materials and ICs.

2. if #1 is satisfied. how i will i know which direction is that source of the temperature reading. say, how would i know if the temperature reading is the one in front of the bot ?


Thank you in advance.

-creedcradle
Title: Re: CAD of new Robot
Post by: Ro-Bot-X on October 28, 2007, 06:05:19 AM
You should take a look at Sandwich (http://www.robotroom.com/Sandwich.html) robot. It uses a comparator, not a microcontroller. Instead of using the sensors for line following, use apropriate (I don't know exactly which kind) temperature sensors to stay away from heat sources. Try a couple of PIR sensors (http://www.acroname.com/robotics/parts/R1-442-3.html) or UV sensors (http://www.acroname.com/robotics/parts/R66-R2868.html).
Title: Re: CAD of new Robot
Post by: Steve Joblin on October 28, 2007, 08:27:21 AM
what is the yellow ball for in the CAD of your bot?

I think you may need to build some type of articulated extendible arm that has a temperature sensor at the end...  I don't know of any sensor that can look 3 meters in front of itself to determine the temperature.
Title: Re: CAD of new Robot
Post by: Admin on October 28, 2007, 10:11:27 AM
Hmmmm well your sensor needs to be IR. Infrared light is emitted from warm objects - the more emitted, the hotter it is. There are handheld devices that you can buy - point and shoot - that give you a temperature readout from a few feet/meters away.

But I havent a clue on how to make it from scratch . . . I would do a search on IR sensor IC's from various electronics distributors and see what you come up with . . .

You will definitely have to do a lot of amplification and calibration to get it to work . . .
Title: Re: CAD of new Robot
Post by: creedcradle on October 28, 2007, 08:31:38 PM
Guys.. thank you so much for your replies.. i appreciate it


what is the yellow ball for in the CAD of your bot?


Ball-type camera.



I think you may need to build some type of articulated extendible arm that has a temperature sensor at the end...  I don't know of any sensor that can look 3 meters in front of itself to determine the temperature.


I was thinking this before, but the arm has to have a high melting point.. that is why i dont like it.
Title: Re: CAD of new Robot
Post by: creedcradle on October 28, 2007, 08:57:59 PM
thanks Ro-Bot-X , i will try to see that page


@Admin

I will be waiting for that.  ;D .. well, i will also do some further research on this..
Amplication isnt really a big problem for me.. as long as i have ways to do it..

Title: Re: CAD of new Robot
Post by: creedcradle on October 31, 2007, 03:04:17 AM
WHOAAAA!!!!   :'(

i found the keyword of what iam looking for.. but the price isnt reasonable for the said "non-contact temperature sensors"

anybody knows a cheap non-contact temp sensor?
Title: Re: CAD of new Robot (need help)
Post by: Steve Joblin on October 31, 2007, 06:03:05 AM
You mean a thermistor?  they are less than a $1 at Jameco... http://www.jameco.com/webapp/wcs/stores/servlet/KeywordSearchResultView?langId=-1&storeId=10001&catalogId=10001&searchType=k&searchValue=thermistor&categoryId=107039&rscount=26
Title: Re: CAD of new Robot (need help)
Post by: Tsukubadaisei on October 31, 2007, 10:28:44 PM
What are those wheels? Are you going to use a steering mechanism? If not you will face problems when turning your robot.
Title: Re: CAD of new Robot (need help)
Post by: frank26080115 on October 31, 2007, 11:35:08 PM
You mean a thermistor?  they are less than a $1 at Jameco... http://www.jameco.com/webapp/wcs/stores/servlet/KeywordSearchResultView?langId=-1&storeId=10001&catalogId=10001&searchType=k&searchValue=thermistor&categoryId=107039&rscount=26


Aren't those supposed to be used very close to what you want to measure? I just don't see them working at long ranges.
I'd personally experiment with a IR phototransistor in a tube with a lens that filters visible light, but it might need to be amplified quite a bit.

What are those wheels? Are you going to use a steering mechanism? If not you will face problems when turning your robot.

Na, he won't, differential drive systems work wonders
Title: Re: CAD of new Robot (need help)
Post by: creedcradle on November 01, 2007, 03:52:49 AM
@Steve Joblin
im not looking for the basic thermistor, we all know that it cant detect temperatures greater than 3 meters.. ;)

@Tsukubadaisei
definitely no steering here.. i need the bot to do turns at minimum ... it can only be done by differential drive ....
I will buy this robot http://e-gizmo.com/KIT/Mobot.HTM  and take out the wheels of it..  ;D



@frank26080115
differential. absolutely right. tell me 'bout your experiment on IR, oopppsss i would not ask the schematics or anything, all i need to know is the general overview like how many stages of amplifier i should possibly use that runs at minimum power consumption... thanks in advance

guys , again . NO ROOM for microcontroller on this robot.
Title: Re: CAD of new Robot (need help)
Post by: Admin on November 01, 2007, 06:41:49 AM
Quote
guys , again . NO ROOM for microcontroller on this robot.
but your CAD has room?

you probably considered this but just in case . . . consider getting an IR camera with visible light filters on it . . . and use basic computer vision to interpret colors as temperatures . . .