Let's Make Robots!

Robot 2, this time /w planning

object avoidance, auto or remote, expandability for peripherals

Now that i can do SketchUp  this allows me to plan my next robot a little better. I am recycling parts from my first robot Kaboodle http://letsmakerobots.com/node/1284

Same plan with better execution, also a larger steadier base that is parallel to the surface. the body will be made from acrylic sheet and cut with a plastic cutting knife + and rotarty tool.

 

New additions i will be trying include:

-use of microswitches for bumpers

-RF link for remote conection

-cliff detection with IR

-IR beacon for docking

 

After staring at the model for a bit i might go with 2 casters instead of 1 and move the wheels closer to the center for more stability, the new caster will be at the rear.I wil aslo move the servo back as to even out the weight distribution, and make it so that the sonar is closer to the center.

 

Design #2

robot2.jpg

 

Addition of bumpers. I will not use microswitches, but 8x reset button switches for this. (little white things in the image)

The contact points  at the bottom will be home made ball casters using: brass tubing, a bearing, and a spring

robo3.jpg

 

Update, Sunday Aug 03

Time to build!

 

This is the base using plexiglass with cutouts for the wheels and nylon standoffs to support the next tier of plexiglass.

plexiglass is a tough process to cut with a rotary tool, next time ill have it lazer cut instead...

Picture_71.jpg

 I originaly made a bearing caster with brass tubing. But it was too tall. If i made it any shorter, the components inside would no longer fit. I would need a smaller tube, bearing, spring and nut altogether. so i decided to try out metal screws as casters in the meantime. I hope they'll perfrom well, its nice because you can adjust their heights too.

http://www.solarbotics.net/starting/200209_ballcasters/200209_ballcasters.html 

 

 Picture_75.jpg

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Nice design, it will be a big robot :P

bwt, i'm trying to use sketchup too, but i can't find a way to precisely give a size to an object.. Is there a box where i can enter  width, height and length ?

Actualy it will be a small-medium sized robot abt 20cm all around. The picture makes it look big. the wheels in the pic are the same size wheels as the robot in your avatar :)

Yes its pretty easy to scale to dimensions! Just start scaling the object, then before releasing the mouse button, type in the dimensions. Example... "30cm, 10cm" or "3.5", 4"" 

Also you can look up the mini video tutorials google has on sketchup, it's super helpful.

what are you going to use for the rf link? oh and what's the IR beacon for docking?

RF link:  http://www.sparkfun.com/commerce/product_info.php?products_id=7815

the IR beacon is a simple emmiter in some corner of the house which projects a cone of ir light. As robot roams around the house, and chances upon crossing the ir beam, it will try to get as close to the beacon as possible and rest there. Well thats the basic plan at least.

i've also purchased that RF link.. i'm waiting for delivery :P does it work well? :)

that's really cool. i am curious about this because i wanted to make a similar thing when i get home in italy (not an ir beacon, i was just thinking of some kind of "parking" the robot could rest on). but i've got some doubts like, how are you going to deal with the bouncy IR signal coming from the beacon?

 

PS: 10 dollars for the RF??? THAT ROCKS!! :) i just have to think whether to buy a transceiver for mine or not

love the robots on here

talking of robots did you see this...Robots Do Have Emotions You Know!
It's known as the "Heart Robot" and has recently gone on display at London's Science Museum. It is the first robots built to show emotional feelings or in effect replicate these feelings as a machine. The Heart Robot is the main attraction at the Emotibots exhibition at the Science Museum.
http://www.webxact.co.uk/2008/07/robots-do-have-emotions-you-know.html

I would shorten up the "pegs" on the corner of the bot.

make your own caster, ill put the info up there too.

http://www.solarbotics.net/starting/200209_ballcasters/200209_ballcasters.html

The one i made felt pretty slick and would seem that it would work like a charm (if only my robot was taller, or my caster parts smaller). if i make new ones, i'd use the springs from ballpens and smaller ball bearings.


A little more info on the home made caster (though it does not work)?