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Registered Member #2431
Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639
does any one know of a 100 USD or so devicethat can range out obsticals for ground and air bots?
I was thinking about those parking aids for cars, but many of them are just ultra-sonic, which i already have. I was also thinking of using the sharp IR distance meters.
I cant use more than two ultrasonic devices beacuse of unsynced chirp-emission. the IR detectors are kinda iffy too.
Registered Member #2431
Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639
Pinky's Brain wrote ...
Scanning doesn't allow you to bypass the diffraction limit.
I just need to be able to see walls and wether a 8 inch dia circle is present or not, would scanning still not work, givin the typical freq?
Carbon_Rod wrote ...
Kinect work well indoors ($100 used):
Radar works in dust, but production units appropriate for UAVs are expensive:
Primitive coffee-can SAR radar projects are documented too:
Cheers,
Yep, the USC team used the kinnect at the 2011 IARC mission 6 event, they scanned my body, and could identify windows and doors( and decide if the were open or closed) and recognise human bodies and depth.
as for the radar, im not sure i can afford them.
and the SAR's ive been looking at, but your sources are better than mine so ill read those over carefully.
Registered Member #2901
Joined: Thu Jun 03 2010, 01:25PM
Location:
Posts: 837
Patrick wrote ... I just need to be able to see walls and wether a 8 inch dia circle is present or not, would scanning still not work, givin the typical freq?
Theoretically If you're working in GHz range then 8 inch is just about doable with a good directional antenna ... for a couple of cm near the centre you would get no reflection. Dunno if NA on those coffee cans is quite good enough to be absolutely certain there's a hole or simply a slightly more radar transparent/absorbent material.
Registered Member #65
Joined: Thu Feb 09 2006, 06:43AM
Location:
Posts: 1155
SAR projects are quite time intensive, but some students re-purpose directional WiFi antenna to reduce build times.
If you want to get started in this area... there are plenty of 30m range Doppler Radar units at around $10 each I became curious about the mdu1620 & HB100 units for an improved dead reckoning project, but none of the app notes really state anything meaningful about their internal design.
From a competitive perspective, I would recommend asking a faculty representative to help arrange "branded" sponsorship from Novelda. So far, I have only heard of one company (Hokuyo) that does not support student research. People become especially cooperative if their brand is credited for trouncing the competition in a televised event, or published works... =)
Registered Member #2431
Joined: Tue Oct 13 2009, 09:47PM
Location: Chico, CA. USA
Posts: 5639
the Hokuyo ones are what everyone one uses, but they have some sever limitations. almost everyone used the 2000 USD, and one used the 6000 USD one(at IARC #6), and they're prone to noise and low bandwidth, much lower than advertised.
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