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Bird Detector

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Jerry In Maine

New Member
We have a wind power generator here at work. It's a 3 blade model and spins very fast.

We're on the coast and have loads of seagulls. They generally do a good job of avoiding the blades but once in a while one gets too close. We've had two blades broken ion the last few weeks and you can guess what happens to the gull.

Curious if anyone knew of a method similar to a PIR detector that might detect the gulls in order to sound a loud horn when they got too close.

Problems I can see are that it would have to detect a rather small body at perhaps 50' or so in order to "intercept" the gulls in time for them to change course. It would also be looking toward the sky and thus migh be overcome by direct sunlight.
 

Pommie

Well-Known Member
Most Helpful Member
I think you need stronger blades.:D:rolleyes:

On a more serious note, would making them more visible deter the birds? Something like concentric rings or a mesmerising spiral?

Mike.
 

Jerry In Maine

New Member
Blades spin so fast that they appear transparent - like looking through an airplanes prop. Tried painting menacing eyes on the housing of the generator w/ no luck.
 

Jerry In Maine

New Member
I've seen a few microwave/doppler units used in alarm systems. Ads say they'll detect a human at 90' so MAYBE they would detect a large bird at lower - but still - usable ranges.

Never played with them though...
 

Jerry In Maine

New Member
Loud horn - maybe add a strobe too.
If I can detect at long ranges some sort of motion (flag, etc) might do to save from having to hear the horn.

The gulls seem to be able to adjust to just about everything except sudden sound/motion.
 

Boncuk

New Member
I agree with Pommie,

your blades are too weak.

They should be strong enough to shred a seagull.

When his/her comrads hear his/her last sound they will avoid the area around your wind generator.

Just enforce the leading edges with a small band of steel.

On the other hand, why does your propeller have to rotate at speeds making it look "transparent"?

By the time any system senses a bird it will be too late already to warn them to prefer a detour instead of flying straight through your prop.

Maybe fire crackers or a gun which fire(s) at irregular intervals will do the job. You might turn it off at night. Seagulls also need some rest.

Boncuk
 
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Jerry In Maine

New Member
It's a name brand higher-end generator similar to this one:

AirX Marine Wind Generator by Southwest Windpower

Blades are of a composite material. This isn't one of those massive generators that you see on a hill side with gently rotating bldes. This one is designed to spin with tip speeds approaching 350 mph. Spin anything that fast and throw what amounts to be a large sized chicken into it and something's going to give.

The birds hover around the water seaching for fish - they're not flying by at MACH speed, so I'm betting that an intermittent warning sounding when one gets a bit close will do the job.
 

ericgibbs

Well-Known Member
Most Helpful Member
It's a name brand higher-end generator similar to this one:

AirX Marine Wind Generator by Southwest Windpower

Blades are of a composite material. This isn't one of those massive generators that you see on a hill side with gently rotating bldes. This one is designed to spin with tip speeds approaching 350 mph. Spin anything that fast and throw what amounts to be a large sized chicken into it and something's going to give.

The birds hover around the water seaching for fish - they're not flying by at MACH speed, so I'm betting that an intermittent warning sounding when one gets a bit close will do the job.
IF, you could detect it, you can get audible bird scarers, that blast out the sound of a gull in distress.

I wouldnt like to be your neighbour, especially at night...:)
 

Andy1845c

Active Member
Detecting them sounds like a challenge. Your goind to need to be able to detect them coming in around 360 degree radius. I am sure it is possible, but I don't know about practical. Have you tried talking to a bird expert to see if there is anything else you could paint or place on the housing to scare them visually? Maybe a decoy of some kind of bird of prey, strobe light, ect.

Also, if you are able to get a detector working, can gulls hear well while in flight? Can they tell the direction the sound is coming from and avoid it, or will they just be startled as they hit the blades anyway?
 
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Sceadwian

Banned
UV reflective paint on the blades? I don't know about seagulls but some birds see in the UV spectrum, if they see the blades they'll be easier for them to avoid. Whistles on the blades that make noise? I don't know what a birds hearing range is but something like the passive whistles some companies sell for dear warning might be appropriate?
 
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tcmtech

Banned
Most Helpful Member
Those POS blades?
Go on eBay and get a good set from windmax or powermax. I have both.:)
In a high gust day I recorded a 2200 rpm peak on my 6.8 ft set. Plus I am 250 pounds and I can stand in the center of one spread across two chairs just like they show in the advertising photo. :eek: The 6.8 ft blades are $50 with shipping now too! :)
And I know from experiance they can take out a large crow with no damage! But it does make a feathery mess! :D
Far as bird deturants, the better ultra sound pest control devices have been proven to work with most birds. ;)
 

tcmtech

Banned
Most Helpful Member
Ford makes the Ranger and the F-250 SD. :p
Just because you own an over priced Ranger doesnt mean the F-250 SD's are a POS too! ;)
 

awright

Member
Boncuk asked, "On the other hand, why does your propeller have to rotate at speeds making it look "transparent"?"

For a given blade diameter, you maximize power extraction from the wind by maximizing tip speed, but want to keep tip speed below sonic velocity to avoid excess noise. Additionally, if you have a gearbox, wear increases with rotor speed. Engineers try to balance the various tradeoffs for best return for the money invested in the machine.

tcmtech's tip speed is 783 ft./sec., about 70% of sonic velocity. The giant megawatt size utility wind turbines that look like they are lazing along actually are operating with tip speeds approaching sonic velocity.

Despite the invisibility of the blade disc, is it possible that an interrupted spiral painted on the blades would be visible, even if the blades themselves are not? Seems like I've seen that phenomenon somewhere - possibly in the "optical illusions" exhibit area at the Exploratorium science museum in San Francisco. The relatively slow apparent movement of the pattern is much more perceptible to the eye than the rapidly rotating blades alone.

Jerry In Maine, you must be in quite an isolated area to consider noise as a deterrent. (I did noise studies for wind farms in Altamont and San Gorgonio, CA because even isolated neighbors miles away complained about the noise. People who did not benefit from the energy production complained - those who did benefit from revenue or jobs, did not complain.)

I tried ultrasonic pest repellers to keep birds off my cherry trees. The birds couldn't care less, even from a foot or two away. Have you tried strobes?
awright
 

Boncuk

New Member
Birds are a safety hazard for aircraft. There are many airports located in the path of travelling wild geese which are much bigger and heavier than a seagull. If they get into the air intake of a jet engine they will leave it shredded, but force the aircraft to an emergency landing.

Those airports employ people who use guns or explosives when they spot birds.

The OP could use a sound generator connected to an amplifier producing a pseudo random noise pattern. Hook up a jackhammer of 5KW power.

Maybe the airblast of the speaker will chase the seagulls away already.

I guess the idea enforcing the leading edges of the blades would lead to a sufficient result.

Boncuk
 

tcmtech

Banned
Most Helpful Member
He does have a good point. When they get up in the higher RPM band they are very hard to see. My 6.8 ft blades get to be nothing more than a shadow at over 500 RPM.
Higher speed is more efficient for smaller blades but they do become near invisable too.

I had a 5 foot homemade blade a few years ago a buddy of mine and I made out of a treated 2 x 6. I put it on a sharp hill behind my dads house and I know on the days when we get 50 + MPH wind gusts (surprisingly common in North Dakota!) They would actualy go supersonic! They were ornamental so there was no load or speed control on them and they would just spin all they could.
 

Jerry In Maine

New Member
We're on a U.S. Coast Guard base - right on the water of course - and get some wicked winds coming off the atlantic. The "overspeed" protection on the generator often hits the brakes to keep the blades from going over their max rated speed.

We've had two gull strikes in the year the generator has been up. Each time the blades are dinged enough to cause them to get a little off balance. At high tip speeds it doesn't take much of an imbalance to cause substantial vibes.
 

Pommie

Well-Known Member
Most Helpful Member
If you paint concentric rings on the blades then surely they will be visible at any speed. My suggestion would be yellow and red as these appear to be the natural danger colours.

Mike.
 
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