Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: Joker94 on June 25, 2009, 07:04:46 PM

Title: alterrain, wheel/treds?
Post by: Joker94 on June 25, 2009, 07:04:46 PM
i am makin a ultralight alterrain robot to drop out of a model plane(yes, that light)

And i don't know what tyre would be the most suitable as there are pros and cons for each type

the options are conventinal rubber tyre or tank like treds

what do people think ???
Title: Re: alterrain, wheel/treds?
Post by: Asellith on June 26, 2009, 07:31:05 AM
How hard is this drop the little guy has to perform?

Treads might be more resilient to impact and you could put a round guard on the outside to make sure the bot lands with one side or the other up so it can move after the drop.
Title: Re: alterrain, wheel/treds?
Post by: SmAsH on June 26, 2009, 08:26:04 AM
how high does he drop from? how much does he weigh? does he get a parachute?
Title: Re: alterrain, wheel/treds?
Post by: 4by4 on June 26, 2009, 03:27:34 PM
The iRobot Ember is a very small robot with treads. I wouldn't think it works in grass very well though. Grass, twigs tends to get pulled into the treads.
Title: Re: alterrain, wheel/treds?
Post by: mdmedlin on June 26, 2009, 10:52:07 PM
I made some lexan wheels with a cog belt as treads, you could try something like that.  The lexan is light and very tough.  You can make the wheels what ever size you want and glue the cog belt inside out to the outside.
Title: Re: alterrain, wheel/treds?
Post by: jamort on June 26, 2009, 11:57:23 PM
something else ou could make is a micro bot which is just about as small as you can make a robot... I was watching a show and they can swarm under doors like little armys and you could probably carry for on a aircraft... the other option it probably foam wheels or maybe some toy offroad tires taht dont way much... but a problem yourgoing to have if its too heavy is it not only lifting it up but controlling the robot...
Good luck
Title: Re: alterrain, wheel/treds?
Post by: Joker94 on June 27, 2009, 02:44:23 AM
how high does he drop from? how much does he weigh? does he get a parachute?

Sorry i forgot to mention, yes of course he will get a parachute that is one of the most important things. If it hasa parachute it won't matter how high the drop hight is as it will reach terminal velocity in a short space of time. but saying that it would have to be over 15 so my electronics will have a long enough time to react so that it can eject the parachuter. As of Yet i have only  started desigh but i have a target weight of a less than 1kg but my plane can lift more weight than that, it can lift 1.7kg but i want to try keep to my target weight

I'll have a bumper on the front made of a stiff plastic curved to absorbe the landing

something else ou could make is a micro bot which is just about as small as you can make a robot...

 I was just reading about that the other day, they are awsome and i hope to tackle something like that sometime this year

@mdmedlin, i think i'll need some thing alot wider than what your wheels were, would it be possible to make them wider and would it add alot of weight
Title: Re: alterrain, wheel/treds?
Post by: mdmedlin on June 27, 2009, 11:01:48 AM
The lexan comes in different thickness sheets if I remember correctly. If you have access to a lathe, you could get a rod of material, drill out the middle and then cut off whatever thickness you need.
Title: Re: alterrain, wheel/treds?
Post by: Joker94 on June 27, 2009, 06:20:02 PM
that may be problem as i don't have access to a lathe :(
Title: Re: alterrain, wheel/treds?
Post by: mdmedlin on June 28, 2009, 03:48:17 AM
The other option would be, assuming that your drilling skills are sufficient, take the rod and drill out the center hole yourself and then take a band saw or a hack saw and cut off what you need. The problem with this approach is that you might not get the hole exactly center and then the wheel will wobble.  The other option would be to order a tube and use that as a wheel.  I am not certain if the acrylic tubes can withstand an impact from that high up or not.  I have seen plastic wheels wheels on this site and other sites, as those might work for you.
Title: Re: alterrain, wheel/treds?
Post by: Joker94 on June 29, 2009, 06:16:07 AM
now i think about it if i did use normal wheels i might have to go for something like a shop bought tyre or  a tyre with a proper rubber tyre so it has some suspension and is able to grip pebbles and other items
Title: Re: alterrain, wheel/treds?
Post by: SmAsH on June 29, 2009, 06:20:58 AM
have it do like the mars rover and inflate a massive bubble around it....
or you could just use a chute and suspension... just get a massive knobby tire...
Title: Re: alterrain, wheel/treds?
Post by: Joker94 on July 18, 2009, 05:19:14 AM
i was planing on placing two tyres or equivelent on the ffront for suspension.to stop every thing shattering ;D
Title: Re: alterrain, wheel/treds?
Post by: RoboChan on July 18, 2009, 09:22:43 AM
You could have 2 arches of some obsorbant material and when it land the arch takes all the energy and then just have servos unhook the arches so you can drive away. What ever you try i want to see a video.
Title: Re: alterrain, wheel/treds?
Post by: Joker94 on July 18, 2009, 07:36:46 PM
ok, i will post a vedio. I am going to build a aluminum box the exact same size with weights that replecate the full weight so i can test for the best option.