Replies to This Discussion

Permalink Reply by captaingeek on November 20, 2012 at 9:33am

how about putting your 2 ideas together.

 

Drop the battery life all together, go tethered and avoid the obstacle of a power source wires?

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Permalink Reply by Shyam Balasubramanian on November 20, 2012 at 11:30am

Hi Captain,

Can you elaborate on your idea. I do not understand the idea of 'tethered' in this respect. Is this area new? What is to be implemented in the area of obstacle avoidance of power source lines, is it with the change in magnetic field one will know that I am nearing the power lines, or via the camera (It must be fully autonomous).

What is wrong with the idea of extension of battery life (by means of say, a collaboration)?

Regards,

Shyam.

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Permalink Reply by captaingeek on November 20, 2012 at 2:52pm

tethered as in plugged in. then you don't need a battery. you can fly indefinitely. you have a 100+ foot long cable plugged into the copter and a power source. it will then need to fly in a manner so that it doesn't cut its own power tether. either using cameras to watch there the tether is or fly in a grid manner and carefully turn so that it doesn't get caught in the tether.

 

 

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Permalink Reply by Shyam Balasubramanian on November 20, 2012 at 6:38pm

Hi Captain,

I am sorry to ask you, but what is the target on implementing your idea? Is it obstacle avoidance (in the way that) of avoidance with its own 100+ foot long power cable and fly in a manner that it does not get entangled in it own power source or will it be something else too?

How will this be useful in the area of the current research in the field of UAV?

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Permalink Reply by captaingeek on November 27, 2012 at 8:52am

The target would be to fly indefinitely while performing commercial or mission operations. Say survey a large field, or crop dusting for example. With unlimited power you have many more options for missions, such as longer endurance, payloads, etc. The obstacle avoidance can be the same as any other drone in addition to avoiding the tether which can be quiet simple.

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Permalink Reply by Luke Nyhof on November 20, 2012 at 6:58pm

Next, think about the weight of 100' of cable (which can transmit at least 60-120A @ 12-24VDC), the weight will not be central, and will impart a asymmetric loading on the airframe, which will lead to poor PID tuning. Furthermore, the amount of voltage drop due to the internal resistance of the cable itself also has to be taken into account... 

Then perhaps think about using a different idea.

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Permalink Reply by captaingeek on November 27, 2012 at 8:55am

You would run a pretty thin cable and wouldn't be using DC current. You would need to use AC voltage and convert it onboard. AC is more efficient for transmission over long power lines. The tether could also be used for real time data and video feeds.

You can then have a very high power CPU in the ground station to do real time image recognition and flight automation.

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Permalink Reply by Stephen R Mann on November 27, 2012 at 10:22am

Also, high-voltage, which would allow smaller (lighter) wires in the tether.

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Permalink Reply by Luke Nyhof on November 20, 2012 at 7:10pm

Regarding the second item, take a look at these links:

http://www.news.cornell.edu/stories/Oct12/RescueRobot.html

http://www.cs.cornell.edu/~asaxena//rccar/

http://spectrum.ieee.org/automaton/robotics/artificial-intelligence...

Just a little light reading to start you off...

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