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Offline ANDY TTopic starter

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new project
« on: February 15, 2013, 12:59:48 PM »
Hi All
I am new to this forum and need lots of advice on how to proceed with this project. I am located in Lincoln Uk so iF there is anyone local more the better.

Anyway i am looking to build some auto turning targets for my local shooting club.
I am not looking to use pneumatics must be full electrical.
 The motor only needs to turn 90 degrees i would like to have full interface control with fully programmable control of timings and combinations. (Three targets in one bank)

What would be the best motors to use, what parts would i need to control the motors 

What control interface would be best, i would like to stick with Allen Bradley touch screen

How would i wire this up, as you can see i need lots of help I do have the cash to commission this but would like to have some part in the build.

So if you can help or know some one that could help please e-mail me.

Regards
Andy

Offline jwatte

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Re: new project
« Reply #1 on: February 15, 2013, 04:32:11 PM »
There are probably solutions from very cheap and cheesy, to full-on industrial quality bullet-proof (literally) automation systems.

You should weigh one of your targets, mounted on its frame, and then measure the width of them (of swinging around a vertical axis centered on the target) and multiply the two together; you will then get a good torque number to look for in a motor (this includes the margin you need to be safe and effective.) If the targets swing around horizontal or other axes, the calculations are slightly harder; you'll probably need a stronger motor than indicated for best effect.

Once you have the right strength motor, you can start looking at ways to physically mount the motors to the ground, and to the target/frames. You probably want a gearbox on the motor if you're using a bare motor. If you're using a servomotor, it may already have a built-in gearbox.
You can also start looking at how to solve the "90 degree rotation" problem. There are two main ways:
1) Use limit switches. Some part of the target/frame bumps into a switch, which tells your controller it's time to stop moving.
2) Use absolute rotational encoders. These tell you exactly how may degrees the target has rotated. Servomotors often have these built-in.
Also, you need an approprate motor driver/h-bridge unit. It should be rated for higher voltage and amperage than your motor requires and draws. You also need a power supply that can supply what the motor needs.

Finally, you need to integrate it all. Depending on which "ready-made" versus "from parts" choices you've made, this may involve microcontroller programming, building IP65-class cables, physical enclosures, etc.

It's really hard to give more advice than this without knowing what kind of budget you're working on, and how much engineering you're willing to do yourself versus buying pre-made systems. For what it's worth, pre-made motion control systems typically charge thousands of dollars for systems that you can self-engineer for a few hundred -- the real cost is in the time it takes to make things robust!

Offline ANDY TTopic starter

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Re: new project
« Reply #2 on: February 15, 2013, 04:54:14 PM »
Hi
I do not really have a budget FOR this but i would say i really do not want to go over 2000 i have already got a Allen Bradley mirologic 1100 1763l16BBB on its way.
I am also looking for a good second hand Allen Bradley touch screen control unit for around 500.

I was thinking of using some wheelchair motors to turn the targets, turn on 24v hold on 12v that should give me plenty of turning power the targets only weigh around 5-10lb and will have a close Center of gravity.

I have the cash but not the know how so need plenty of help.
This is for my local shooting club which is small only 100 members i would like it to be real professional job with better control than you would get of the shelf.

There is not much you can get of the shelf hear in the UK and what there is is not very good.     
Andy
« Last Edit: February 15, 2013, 06:06:11 PM by ANDY T »

Offline ANDY TTopic starter

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Re: new project
« Reply #3 on: February 15, 2013, 05:10:35 PM »
See attachment

Offline jwatte

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Re: new project
« Reply #4 on: February 15, 2013, 09:10:43 PM »
Quote
There is not much you can get of the shelf hear in the UK and what there is is not very good.     

Don't you have food processing plants, factories, and similar environments? Those run all on motion control, and I'd be surprised if there's nothing good available.
Whether there's anything within budget available might be a different question :-)

I don't know whether your controller is good for this application or not -- I'm not an industrial automation guy. However, if you go with Allen Bradley, it seems like their Kinetix series of servo drivers, coupled with suitable encoders and motors, would do fine and be mostly plug-and-play. Most of them look like AC servo motor controllers, though. Nothing wrong with that -- that'll give you all the power you need :-)

Offline ANDY TTopic starter

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Re: new project
« Reply #5 on: February 16, 2013, 03:51:23 AM »
Quote
There is not much you can get of the shelf hear in the UK and what there is is not very good.     

Don't you have food processing plants, factories, and similar environments? Those run all on motion control, and I'd be surprised if there's nothing good available.
Whether there's anything within budget available might be a different question :-)

I don't know whether your controller is good for this application or not -- I'm not an industrial automation guy. However, if you go with Allen Bradley, it seems like their Kinetix series of servo drivers, coupled with suitable encoders and motors, would do fine and be mostly plug-and-play. Most of them look like AC servo motor controllers, though. Nothing wrong with that -- that'll give you all the power you need :-)

Hi
Yes you are probably right about using a servo but as i have said i have very little knowledge in this area and more or less need to be told what to buy and how to fit it.
I really need someone to hold my hand on this or find someone that could build it for me at a good price. 

Andy

Offline briselec

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Re: new project
« Reply #6 on: February 16, 2013, 03:06:05 PM »
I'd suggest you post about this on the forum at MrPLC.com.  Hopefully someone on that site who lives local to you can give you a hand.
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Offline Webbot

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Re: new project
« Reply #7 on: February 16, 2013, 08:01:05 PM »
Hi Andy,
I'm in North Yorks, and frequent a local clay ground, so have some sympathy.
However - think your looking at the problem the wrong way - you've bought a 'user interface' but haven't thought about the sharp end.
Twisting a target thru 90 degrees screams servo to me - not motor.
But your light weight targets are probably mounted on posts (wood or metal ie weight?) and need to be coupled to the servo/motor somehow. Shots to the outside of the target probably produce little force on this coupling. A bulls-eye probably makes a large force on the post and hence the post to servo/coupling ?
Presumably the coupling will be out of site - hence no direct hits on the coupling.

So personally I would look at how you are going to mount/couple the target to the servo and get that working (mechanically).

Once done you probably then just need to look at how to wireess-ly control the servo.
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Offline Tommy

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Re: new project
« Reply #8 on: February 17, 2013, 07:27:28 AM »
Quote
i have already got a Allen Bradley mirologic 1100 1763l16BBB on its way.
ANDY T, if this is a project you plan to do yourself IMO, list the Allen Bradley mirologic on e-bay for sales,
and order a Automation Direct or similar system, one that has affordable software and free customer support
(Like Automation Direct). IMO the only reason for using Allen Bradley is for large factory Automation
projects that have large budgets and pre-existing Allen Bradley systems(in house service personal are familiar with).

I agree with briselec, post question on PLCtalk.net or MrPLC.com.

If this is a prototype(testing concept) , a PC based system would cost much less and include a touchscreen monitor.
Stepper Motor drive @$300.00 per axis(Automation Direct)(uses 110Vac)
Servo Motor drive @$1000.00 per axis(Automation Direct)(Needs 230Vac)

Tommy

 
« Last Edit: February 17, 2013, 08:00:17 AM by Tommy »

 


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