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Author Topic: Biting off more than I can chew. SO overwhelmed by the knowledge here.  (Read 1938 times)

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Offline gericurl76Topic starter

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1st post, here goes:
I cannot describe how small I feel among you guys.

I am a graphic designer by trade preparing to go back for my master's degree in the fall. I am totally a design/art-minded person. I did excellent in geometry and physics classes, but most math escapes my tiny brain.

The reason I am here is, I am outfitting my truck:

to be a search and rescue vehicle. I'm off to a good start, but my latest idea has led me to this site.


Too often rescue operations go on at night so I find myself needing a good exterior lighting system.
My plan for the roof lights is to make them pan and tilt using an inside controller. Inspiration came from this system from Lucrum Industries:
Lucrum Lighting System Prototype Demo

Lucrum is no longer making this system (not to mention the $1700.00+ price tag it had). It also had some limitations that I hope to overcome (with a lot of help from you guys)

My design goals:
•Lights (4, usually two spot beam and two flood) will pan 360º and tilt about 135º up and down.
•The system will be mounted to the top of the truck to an aluminum roof rack (Baja Rack is already on board to help design/fabricate the roof rack http://www.bajarack.com/)
•Although my truck is garage-kept, it spends much time off the beaten path. Not to mention the vast majority of search and rescue operations are no where near pavement. So the system will have to withstand harsh weather, constant airflow at freeway speeds, and a good amount of jostling when driving over rocks and streams etc...
•Lights should be removable/ interchangeable in the event that one is damaged or better lights are obtained.
•Estimated size of lights is 4"-6" diameter (currently I am compiling dimension specs on the most popular options available)
•The Lucrum system (youtube video) I believe is set up on linear actuators which limits the angles. I am guessing I will need to set them up on servos to achieve the desired rotation.
-Servos would need to be somewhat water proof.
-Able to withstand the bumps of living on my truck
-Strong enough to tilt or rotate the lights. I'm guessing they weigh <2lbs each but I'd prefer to over-build rather than have to re-do later. I can't think of a situation that would require the use of the roof lights at any speed over 25 mph (conservatively faster than actual expectations).
•Each light I'm guessing, will have to be on a 2 servo system. The lesser option would be to have each one pan on a servo, and have one servo on a rod to tilt them all. The problem with that solution is when you begin to aim off to one side or the other and then tilt, the tilt becomes increasingly less as the angle from center approaches 90º.
•I would like the panning speed to be 180º in ~3 sec. (adjustable would be even better, though not necessarily from the cockpit)
•Currently I plan to replace the gear shifter in the truck with a flight control stick from an A-10 warthog/thunderbolt. Exactly like the one pictured below:

The idea is to use the china hat to control the pan and tilt. Also once the system is turned on, the trigger will activate the roof lights (momentary switch). The top thumb button will act as a switch for the same roof lights (press=toggle on, 2nd press=toggle off), and the pinky and half-shaft buttons will toggle other lights (Tantrum system:http://www.visionxusa.com/led/tantrum/  and rear facing lights)
-The Flight control stick is more robust than the small joystick solution that shipped with the Lucrum system. Also it consolidates the controls so you are not having to feel around for them while driving in generally "less than ideal" conditions. To top it off, I think it is just pretty dang cool.
-The flight control stick has a 17 pin connector on the bottom (each pin is labeled with letters a-m around the outside and n,p,r,s,t on the inside). There are a total of 8 "buttons" on the stick, which leads me to believe that there are 2 pins per button, and an extra one to ground them all (again I am no electrical engineer)? I plan to use a standard electrical tester by trial and error until I figure out what pin goes with what button (any thoughts?)
crappy pic:

-The servos/mounting system must consider the electrical lines going to the lights and allow for full pan and tilt without damaging the powering wires going to the lights. (cords may span from rear mounted ballasts if I decide to go HID) although I'm liking everything about these LED's: http://www.visionxoffroad.com/led/s6100/ except the cost.
•I will be incorporating an air dam to help protect the lights when not in use (I'm hoping to program them to face to the rear and down towards the roof when not in use to help protect them). The air dam does not need to move like the Lucrum (youtube video above) unless it is necessary to avoid collision with the lights as they tilt.

Holy Crap! So I'm now staring at this seemingly insurmountable project (due to my limited brain functions) with a lot of determination, but needing a lot of help. I have many fabrication skills/tools in my garage, and I have welders and machinists, powder-coaters, etc that I can access to fabricate if I need to. If anyone feels compelled to help me in any way possible I will always give them the credit they deserve. Also I can offer my graphic design skills to help you make your pitch to NASA as polished and professional as possible. I specialize in branding and logos, but I can do most any design.

A few initial questions:
1- I have searched servos for days and still have no clue where to begin. Are the hobby motors durable/strong enough? I've read about 10 different ways to "water proof" a servo, and saw that Traxxus makes them now. I do want to "overbuild" a bit but I don't need a servo that could steer a lincoln.
2- Do you see any fatal flaws in my thinking/design that can be modified or improved?
3- I'm considering one of these for each mount

but $90.00 each seems expensive. I wonder if I could build my own for less.
The gear has a hole through it which would allow the power cords to go through. Does anybody have any feedback about that idea?

I am open to all suggestions and willing to compromise some functionality if need be.

Thanks for taking time to read this.

Brett
« Last Edit: December 09, 2009, 01:52:03 PM by gericurl76 »

Offline GearMotion

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Re: Biting off more than I can chew. SO overwhelmed by the knowledge here.
« Reply #1 on: December 09, 2009, 09:02:44 AM »
Wow! This looks like an absolutely fun project.

Can you team up with a few people that have varied experience in electronics and mechanics? You have "bitten off more than you can chew" only if you expect to know every step it takes to do this. If you have some local help, and some help here then this is a reasonable project.


Edit:

I do have something you might consider. If the mechanics of a system that rotates/pans the full number of degrees is too difficult or expensive, it might be easier to have lights that rotate 90 degrees cover the front of the vehicle and another set on the side that takes over (perhaps overlaps) the location of the moving spot of light. Another on the back... It might be worth weighing the option and cost of duplicated simple systems over that of a single expensive one.

Another option is to have a fixed upward pointing light, and a tilting mirror rotating around the light to reflect the beam where you want it. All under a dome.
« Last Edit: December 09, 2009, 09:17:14 AM by GearMotion »

Offline definitionofis

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Re: Biting off more than I can chew. SO overwhelmed by the knowledge here.
« Reply #2 on: December 09, 2009, 10:06:29 AM »
... or buy night vision goggles and have no lights and no servos and no mirrors.
Just kidding.  :D

Offline gericurl76Topic starter

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FJ Cruiser project continued...
« Reply #3 on: December 09, 2009, 01:32:24 PM »
Wow! This looks like an absolutely fun project.

Can you team up with a few people that have varied experience in electronics and mechanics? You have "bitten off more than you can chew" only if you expect to know every step it takes to do this. If you have some local help, and some help here then this is a reasonable project.


Edit:

I do have something you might consider. If the mechanics of a system that rotates/pans the full number of degrees is too difficult or expensive, it might be easier to have lights that rotate 90 degrees cover the front of the vehicle and another set on the side that takes over (perhaps overlaps) the location of the moving spot of light. Another on the back... It might be worth weighing the option and cost of duplicated simple systems over that of a single expensive one.

Another option is to have a fixed upward pointing light, and a tilting mirror rotating around the light to reflect the beam where you want it. All under a dome.


I was laying in bed last night thinking about this. I realized hadn't thought of a few things in my design. 4 lights in a row will give a good wide beam as long as they are pointed forward (0º). However, as the beam's angle approaches  90º(left or right) they overlap each other and begin to hit the backs of the adjacent lights resulting in the light output reduced to 25% (wasting 75%). Then as I contemplated the added difficulty of making servos rotate 360º, I realized that rear facing lights mounted at the front of the vehicle is not a good idea.

Maybe I only add the pan/tilt motion to the outside two lights with a 270º(ish) pan radius. I already have a mount for 2 stationary flood lights on the back, and chances are I won't be doing much "searching" behind me, the rear light will primarily be used for working (Stabilizing patients, fixing broken ATV's, organizing volunteers, etc...)
Revised Plan:


I have been thinking about soliciting some students from the engineering dept. at USU here to help me. And I've got a good electrical engineer friend from the FJ Cruiser forum that I chat with very often that will be excited to help on this project, and some guys I can call locally from my old R&D job at Icon Health & Fitness (we prototyped home fitness equiptment). You are SOOO right about getting help, I do tend to want to understand how things work (mom quit buying me mechanical toys at a young age).


The night vision goggles comment is not a particularly bad idea, (I think some guys use them for S&R)  This would be cool
Thermal imaging camera with pan and tilt:

but it is $20,000+

 
« Last Edit: December 09, 2009, 01:52:38 PM by gericurl76 »

Offline Soeren

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Re: Biting off more than I can chew. SO overwhelmed by the knowledge here.
« Reply #4 on: December 13, 2009, 02:06:32 PM »
Hi,

To avoid the overlap, you could let the entire platform/bar rotate.
Even with the bar static, you could moveall four lamps by a sprocket wheel on each and a chain turning them all, or intermediate sprocket wheels, so turning one will turn them all.
The rotating platform would be easier to do though and will cover all angles, but will probably have to be locked in position during regular driving (can be done automatically as well).

You shouldn't go for a (R/C) servo. A DC motor of a suitable size will be easier to control with your hat switches and you can find one that is suitable in a junk yard - a seat adjusting motor would be strong enough I'm sure.
A servo needs a set position to go to, while you probably wanna steer the lamps to a position by eye and then leave it there.
Regards,
Søren

A rather fast and fairly heavy robot with quite large wheels needs what? A lot of power?
Please remember...
Engineering is based on numbers - not adjectives

Offline gericurl76Topic starter

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Re: Biting off more than I can chew. SO overwhelmed by the knowledge here.
« Reply #5 on: December 14, 2009, 12:55:59 AM »
Hi,

To avoid the overlap, you could let the entire platform/bar rotate.
Even with the bar static, you could moveall four lamps by a sprocket wheel on each and a chain turning them all, or intermediate sprocket wheels, so turning one will turn them all.
The rotating platform would be easier to do though and will cover all angles, but will probably have to be locked in position during regular driving (can be done automatically as well).

You shouldn't go for a (R/C) servo. A DC motor of a suitable size will be easier to control with your hat switches and you can find one that is suitable in a junk yard - a seat adjusting motor would be strong enough I'm sure.
A servo needs a set position to go to, while you probably wanna steer the lamps to a position by eye and then leave it there.


I thought about the single bar/platform for the lights but the swing radius would be huge, and seems like it would be more breakable. The sprocket chain idea is good. I will investigate further.

Offline madchimp

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Re: Biting off more than I can chew. SO overwhelmed by the knowledge here.
« Reply #6 on: December 14, 2009, 07:02:10 AM »
I think it would be really cool if you build some sensors into a hat and set it up so the lights were pointing where you look :)

Offline corrado33

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Re: Biting off more than I can chew. SO overwhelmed by the knowledge here.
« Reply #7 on: December 25, 2009, 09:17:05 PM »
Just my two cents... but to avoid overlap when the lights turn... you could A. space them out as much as possible, and B. turn the whole "bar" a little bit, while turning the actual lights..  Although that's more complex...

 


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