pivot motor

[taintedplay]

ok, im building this

http://upload.wikimedia.org/wikipedia/commons/6/66/RIM-116_Rolling_Airframe_Missile_Launcher_2.jpg


the computers (4 rackmount style, maybe more) will be in the actual missile bay turret part. i want this thing to be able to pivot using a motor up and down. where should i put the axle to maximize performance of the motor? almost all of the wieght will be on the back btw

[crazybillybob]

your base will need to weigh more then the turret part and extend out further to keep the stable. So I'd go with a ring gear with a horizontal mounted motor for the horizontal rotation. and a vertically mounter motor to a gear to drive your pitch. This way the motors can be hidden in the base and in the support am. Your going to need to mount two roller bearings one n either side of the turret for the up down motion. and one large diameter bearing in the based for the horizontal rotation. The base bearing will need to be able to support the wight of the arms, the turret and the servers, so a 300LB rating is called for. If it's balanced right each of the side bearings should only need to support 1/2 the load minus the weight of the arms... 150LBs rating is smart here.
These bearings will be easy to get, if you not sure what I'm talking about drop me a line, I can send you s list of suppliers that have them.

To answer your other Q that's posted out there... Metal in the arms and base. metal frame in the area for the servers (think mini rack like) then use plastic fro all the decorative parts Sintra (PVC board) can be worked with wood tools the joints are chem welded (with the glue you buy @ lowes or Home Despot!) It's strong, light, and paints smooth like metal. If you have some Q's on where to get the stuff, ad how to work wit it drop me a line.

This a cool Idea, but needs to be designed well to keep the equipment and you safe !!

CBB

[rendermandan]

This might work for you. That site has lots of stuff that could help you out on this. http://www.lynxmotion.com/Product.aspx?productID=578&CategoryID=103

[taintedplay]

your base will need to weigh more then the turret part and extend out further to keep the stable. So I'd go with a ring gear with a horizontal mounted motor for the horizontal rotation. and a vertically mounter motor to a gear to drive your pitch. This way the motors can be hidden in the base and in the support am. Your going to need to mount two roller bearings one n either side of the turret for the up down motion. and one large diameter bearing in the based for the horizontal rotation. The base bearing will need to be able to support the wight of the arms, the turret and the servers, so a 300LB rating is called for. If it's balanced right each of the side bearings should only need to support 1/2 the load minus the weight of the arms... 150LBs rating is smart here.
These bearings will be easy to get, if you not sure what I'm talking about drop me a line, I can send you s list of suppliers that have them.

To answer your other Q that's posted out there... Metal in the arms and base. metal frame in the area for the servers (think mini rack like) then use plastic fro all the decorative parts Sintra (PVC board) can be worked with wood tools the joints are chem welded (with the glue you buy @ lowes or Home Despot!) It's strong, light, and paints smooth like metal. If you have some Q's on where to get the stuff, ad how to work wit it drop me a line.

This a cool Idea, but needs to be designed well to keep the equipment and you safe !!

CBB


well the turret wont be too balanced because of the rackmount and psu's, so i probabbly would go with a slightly higher rated roller bearing to be safe. also, i still dont get how the motor would line up and work for that. is this like a standard servo?

[crazybillybob]

Based on the weights your talking servos are out (ok not all servos but the ones your thinking of when you say servos are) your looking at standard DC motors (drills, Scooters, electric bikes, etc)
The motors don't need to be crazy big if your balance is close (you may need to mount a counter weight in the unused end of the turret) . For the vertical movement, you should use a gear fixed to the turret. Then a smaller gear on the motor (increases torque, decreases speed) the gears can mesh at a right angle this allows the motor to be mounted vertically yet still rotate the turret up and down.
For the base rotation, I'd just you a friction drive. Mount the motor horizontally , with a wheel on the shaft. The wheel presses up onto the bottom of the turret, allowing it to rotate. Many carnival rides are driven like this.

Use a speed controller to regulate how fast the motors turn...control it with a phiget interface board...and bobs your uncle!

[taintedplay]

Hat size and material should the axle through the turret be?

[crazybillybob]

All you questions have really got me bran juices flowing! I've got a pretty good Idea how to design the basic structures of the frame for the arms and turret. If you can give me a few days I'll toss them into CAD and post you pics so you can understand...Cool if not let me know!

What size base are you going to use 2 foot square or three?
Are the servers in 19" rack mount chassis or custom built? this info will help me setup the scale!


CBB

[crazybillybob]

ok it may take me more then two days to get everything together.... Wouldn't you know before this all came up I had nothing to do...now I'm kind of busy for the next few days.... but I'll get you some drawings!!!



CBB

[taintedplay]

sorry i hadent checked the forums ina few days. i have already started building the frame of the turret. ill put pics up tonight if i can

[crazybillybob]

PICS????

:pics: