Bald Eagles nest monitoring needs Technical Support

[robstaples]

I need some engineering support. My application is putting a camera on the top of a pole to watch a bald eagles nest. I have various options for poles and cameras. The camera I want to use is 17 lbs and the one I have up now is 9 lbs. This will be in addition to the one I have up now.
So I am specifically wanting someone to tell (or point to) the formula for frequency of oscillation of a weight on the end of a pole: base fixed and weight up in the air. It is like a inverted pendulum with a stiff string. But the forces are all different. Heavier weight and less stiff pole, and longer pole will make the movement greater.
What are known are:
the weight of the camera on the end
moment of inertia of the pole( will vary with material and dimension)
and length of pole.
I've included some pictures because we all love pictures. This nest is in my front yard and this camera is 80 yds away in my back yard, on top of a 40 ft black pipe pole. I want to extend my tri leg tv tower with a single pole with camera on end.
Eagle summary: Parents here for 2nd year, nest 106 up in white pine, had 2 eaglets, raised both, first to fledge broke his wing after 5 days of flying. Local eagle rescue has him and may return after healing in 3 more weeks. Remainder is being taught to scavenge and fish. Parent dropped 12 sucker on my walk way within sight of the nest. Eaglet didn't fall for it, ( or come down for it) so parent came down and ate it, 12 hours later. Great entertainment!
I will be using my Kubota to man-handle my tower during modification.:

Thanks in advance,
rob

 

[Tdog]

Great pictures Rob!
I'm neither an engineer or physicist, so I'm no help for your questions.
You might try sending an email to the Dean or Chair of Engineering or physics at a local university.

Good luck.

Jack

 

[Streetcar]

Your primary loading will be wind
What are the sizes of the cameras
Nice pictures

 

[robstaples]

They are both ptz pan tilt zoom. Small is socker ball and 8 lb, larger say basketball size and 17 lb . That wind area would include the connecting mount. Mo.st have a wall to top of camera mount.

Jack, yes the Uof Mich is in town. I'll try for a conection. Thanks

 

[Streetcar]

How high do you want the camera mounts?
Have you considered mounting on a flag pole?

 

[robstaples]

I'm looking to go up 80 to 100 ft. I'm considering extending the center pipe of a tri leg antenna tower. I need to understand the movement frequency based on pipe stiffness. ( size material,etc) Freeway light towers would be great but they are out of my budget. Tall flag poles are expensive because of the wind load. I have trees up that high, but I went up part way and started to cluck.

 

[Streetcar]

Rob
A pole ,100 ft high, will have a serious load on it. You will need a crane to safely install a pole that size.
At work they used 20 ton crane for 50 ft llight pole. The crane was at capacity in light wind. The light was slightly bigger than basketball and weighs 20 lbs
Have you checked electrical contractors to see if they have a used pole. Many times they are sold for scrap value

You could use a small truss with guide wires

Dave

 

[westcliffe01]

Rob, I see you are in MI.

Why is a pole mounted camera your primary choice ? When I visited NYC there was a crew observing an eagles nest on Woody Allens apartment and they had a ground mounted astronomical telescope to which they had fitted an adapter and a VCR. For such an application, a concrete pier poured in a cardboard tube would be an ideal stable platform. Piers

To do what you are suggesting your best bet would be a tilt over tower and the main tower has guys to stabilize it. 2 sets of guys will take a lot of the movement out of things. Holding something up in the air is one thing, but having the pole perform the job of a precision optical platform is a totally different matter. The problem is that a tube has so many potential vibrational modes and torsion is a prety significant one the longer it gets. I think all of the camera mount systems used in the movie industry are gyroscopically stabilized and the camera is gimbal mounted so it will stay level as the vehicle moves.

 

[MossRoad]

Before you go through the trouble, better make sure you won't get a big old fine for disturbing the eagles while putting a pole up next to their nest. Sound ridiculous, but.... you never know.

 

[MossRoad]

Here's some federal guidelines...

In a nutshell, it says don't do it when the nest is active. Do it in the off season or your likely to get fined.

https://www.fws.gov/southwest/migratorybirds/docs/Eagle Nest Camera Guidance.pdf

Also, check with your state for state regs regarding this.