The Next Project - NMO - Vic Goto page Previous1, 2, 3, 4, 5Next
Author
Thread
NMO Experienced Roboteer
Joined: 16 Jun 2004
Posts: 486
Location: Melbourne
sorry closest thing I had in program to peizo device. only used to indicate float down anyways so can be omitted. Pin 1 is top left
Tue Jan 31, 2006 1:22 pm
Rotwang Experienced Roboteer
Joined: 15 Jun 2004
Posts: 1589
Location: Vic
quote:Originally posted by NMO:
Also in the works is an automated weapons control system ie sense the presence of another bot and fire weapon. May not be that useful in a fight but will be damn cool.
Could be handy if you were trying to attack another bot and controlling your bot from a bunker 50 or 60 meters away, sounds to me like the UltiBot’s meeting has got you thinking.
If I remember correctly Suicidal Tendances had a spear triggered by ultrasonics.
Wed Feb 01, 2006 11:26 am
Knightrous Site Admin
Joined: 15 Jun 2004
Posts: 8511
Location: NSW
quote:
If I remember correctly Suicidal Tendances had a spear triggered by ultrasonics.
That was 101 built by Mike Franklin (Also built Anarchy). It used sensors to fire the 750psi spike at the opponent when they came closer then 6 inches. _________________ https://www.halfdonethings.com/
Wed Feb 01, 2006 12:13 pm
kkeerroo Experienced Roboteer
Joined: 17 Jun 2004
Posts: 1459
Location: Brisbane
101 had infra-red sensors for the weapon but a robot that does use ultrasonic sensors to fire a flipper is Hexy Jr built by team Whoopass. Check out the testing videos here:
http://www.teamwhoopass.com/BattleBots/Bots/HexyJr/Construction/default.asp?Page=8
I like it. It helps when your robot is facing away from you. _________________ Get Some!!!
Secretary of the Queensland Robotics Sports Club inc.
Wed Feb 01, 2006 3:33 pm
NMO Experienced Roboteer
Joined: 16 Jun 2004
Posts: 486
Location: Melbourne
I was thinking of using IR to detect, it seams fairly simple. my only worry is the IR present in the areana lights. I have a couple of ways to fix that, 38Khz encoding, or detect the ambient ir and subtract that from the fire value or something.
Wed Feb 01, 2006 6:27 pm
Spockie-Tech Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
modulation is supposedly the way to go when it comes to ignoring ambient IR sources..
Not that I know from personal experience, but I have read a few application notes and that seems to be the solution they all suggest. _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Wed Feb 01, 2006 9:26 pm
DumHed Experienced Roboteer
Joined: 29 Jun 2004
Posts: 1219
Location: Sydney
most off the shelf IR transmitter / receiver modules are 38KHz modulated / demodulated already, so they're pretty easy to use _________________ The Engine Whisperer
- fixer of things
Wed Feb 01, 2006 11:12 pm
NMO Experienced Roboteer
Joined: 16 Jun 2004
Posts: 486
Location: Melbourne
Unfortunetly the issue I see with 38khz modules is that they have a range of a few meters, hence they would probably bounce off the areana walls and tell the bot that there is something there all the time.
Thu Feb 02, 2006 7:42 am
Spockie-Tech Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
Mount the Tx and Rx modules at an angle to each other, down a tube (like on the bottom of an optical mouse), and that should reduce its ability to pickup reflected IR from any source. _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Thu Feb 02, 2006 8:34 am
Spockie-Tech Site Admin
Joined: 31 May 2004
Posts: 3160
Location: Melbourne, Australia
Hope it proves useful to you Neweyn and other MicroCoders _________________ Great minds discuss ideas. Average minds discuss events. Small minds discuss people
Wed Feb 08, 2006 10:45 pm
NMO Experienced Roboteer
Joined: 16 Jun 2004
Posts: 486
Location: Melbourne
Great stuff!!! Just what I've been looking for. I had wondered weather it was possible to use the same micro to do the detection. I remember at TAFE when we had to make an ultrasonic tape measure in micro's class that we could use the same micro but the issue I see is the massive speed difference between the speed of sound and the speed of light anyways thanks brett and mel, that is well worth checking out.
In other news Mat and I did some range testing yesterday of the floating failsafe's.
Details so far you need one failsafe board per channel as the picaxe 08M has an issue that it cannnot drive 2 servo channels (both channels go stuttery if you try) seams to be an issue with an internal timer in the picaxe
The board takes 2.2 seconds to failsafe I hope that is not to long.
We had the bot in my garage which in theory at least should work as a faraday sheild and the floating failsafe boards gave around another 4 - 5 meters range.
Sheilding of the servo leads and micro board is very important or the micro ends up feeding even more noise into the system.
Possible upgrades would include opto isolation for the receiver.
Thu Feb 09, 2006 6:23 am
NMO Experienced Roboteer
Joined: 16 Jun 2004
Posts: 486
Location: Melbourne
Well it's been a buisy couple of weeks and I haven't had any time for robots. However I did get some time to write some more failsafe code.
The issue with the origional code was that at 4Mhz it took 0.65 seconds for it to return a value when the receiver was turned off (pulsin timeout)
I had previously tried to write code at 8Mhz but the servo command does not work
I've written a simple floating failsafe that will allow any good pulse through and will failsafe after 3 bad pulses and will test it today.
3 bad pulses * 0.32Seconds is 0.96 seconds to failsafe, much more acceptable.
Sun Feb 26, 2006 9:03 am
NMO Experienced Roboteer
Joined: 16 Jun 2004
Posts: 486
Location: Melbourne
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum