Hello friends. I have been given the job of making a road marking machine automatic... It contains a simple engine, a compressor....etc. Currently it is man driven.... i need to make it automatic so that it can be made to operate without a man meaning controling its speed and also the amount of spray corresponding to that speed.Ok guys start sending your creative ideas !!!

I am assuming that you mean automatic but not completely unmanned? as in retain manual steering and direction, just automate the speed rate, feed rate of spray and on/off control as in centre line marking etc?
In the case of the motorization, I would look at a Gasoline engine that has a speed govenor, these offer fairly good control.
To control both spray output and required on/off for instance in a dashed cente line, you would need some kind of intelligent logic.
For that, I would consider a 12v/24v DC battery supply for a PLC & 24vdc paint control solenoid(s).
The input could be a simple encoder wheel on the axle that measures the distance run and a LCD/keypad operator input panel to program the desired spray amount/pattern.
The hardest aspect and maybe the most costly part is coming up with a suitable variable paint flow valve, servo valves are expensive.
I assume there is an existing valve which is man-operated? If so this could possibley be automated with a stepper or small servo.
If the machine travels for some distance without recharging, an alternator system could be used in conjunction with the batteries.
Al.

Thanks man.... thank you so much..... Your reply was quite helpfull and detailed. But my problem is much easier one. It doesnt have to paint the white lane which has periodic application on the center of the road... it just needs to paint the continous yellow line that are on the sides of the road. I am sending its old version pic.... tell me what should i add-in to get it automated ! YOU OTHER EXPERTS CAN ALSO HELP AS IT IS HIGHLY NEEDED !

I certainly doubt if it could be trusted to run in a robotic fashion in this environment, too many variables.
If it is just paint flow and speed, (not steering etc), I think you will still need some automation, which is not necessarily simple.
Bare minimum, You need a means of measuring the speed and also a way of controlling paint flow, for practical purposes, this pretty much eliminates a purely mechanical system, I would think.
Which brings it in to the realm of electrical/electronics, the cheapest method apart from the one I suggested, would probabally be a PIC based system.
That would be my approach, hopefully you get some other suggestions.
Al.

what if i forget the steering? just want to make it run by a motor and steered by man.... and fix the flow of paint... then what would you suggest? how should i make it run on the motor? I mean what setup would you suggest ?

I have noticed this forum is filled with many experts who give very vital and detailed help to those who are seeking it... I have been given this project of a road marking machine that paints a yellow continous strip on the edges of the road... the old version was man pushed... thus there was no quantized speed plus no idea of how much paint be sprayed from the nozzle gun onto the road.... it was all dependent on the skill of the worker using it. I wanted to ask you people that as the machine does have a gasoline motor and a compressor what can i do to make it "automatic". Im sending its picture so that it can be easyh for you to come up with your creative ideas. Thanks!

Looks like they need to update the stripping machine... Mine is airless... Not so much over spray...

I think that gps comunications are still to slow to update, and most have an error of a meter or more...

Although, you maybe able to triangulate off the same aviation towers (I can't remeber what they are called specifically).. I used this system fishing, both were great but the triangulation was like a pin on a map.. spot on...

I would also just check the internet for NASA's moon rovers.. This is going to be a costly endevor, I think...

If you get it to work, I want a lawnmower?

Makeing it go is no problem, makeing it go where you want it in a paraking lot and road is going to be an adventure.. Patentable, and very sellable...


Good Luck...

You totally got me wrong buddy.... i want it not to follow some gps stuff.... it will be steered along the roads by a worker.... it wont be just hand pushed this time... it will by run by a motor... maybe the same motor that is already present on it to drive the compressor.... i want you to give me an idea of how to set that up ok ?

Ok... To make it simple. Just hook a hydrolic pump to the exsisting gas motor via belt (sure)..You need a tank.. Then on the left and right wheels mount hydrolic motors,, a few control valves, and off you go? You could even use electronic valves to go remote control?

This should work for you, Buddy... I thought you wanted to get rid of the man, that's why I said gps..

I have mine on a snapper comet lawn mower... lol, it works great..And a floating head since parking lots around here very so much, it keeps the stripe all 4 inches, even in low and high conditions...

Good luck..

I think the old nav system he is speaking of is RNAV.

BTW, why can this unit not be mechanically timed? (as far as the speed/paint volume thing?)

I would think the Lawn mower example is one of the easiest ways to implament this. If you compressor motor is running constantly at a fixed speed you should be able to use it as you locomotion source. Add a shaft driven by another belt from the motor. Make it a fixed distance, but have it swing down and engage the wheels for power. Use that motion to turn on/off the sprayer. If you want variable speed, use a variable speed belt setup (pully sides seperate to change pully diamater/speed) and use the pully sided motion to adjust your spray amount. Alternativly you may be able to use throttle for speed if the compressor can handle the changes in speed.

Simplified I know, but that seems to be the basis of what you want.

Dale

Dale my man.... you are the answer to my prayers dude.... i liked your idea alot... but could you elaborate a bit more on the..."Make it a fixed distance, but have it swing down and engage the wheels for power. Use that motion to turn on/off the sprayer." plzzzzzz........ thanks a million dude!

I gotta see the video of this things madien voyage....

Please, please, please, make a video.


Comet makes a good clutch that has 2 clutch like pullies. The one on the motor grows and the one on the jack shaft shrinks as the rpms of the motor increase... They make clutches to handle 3-85 hp (I think).. I have 2 of them on gokarts that are 13 hp.. They work dandy...


Faisal Durrani What country are you in? Or state?

You may need to modify it a bit to fit exactly what you need.

Output shaft: You will have a shaft that presses down on the wheels to power them. You may need to try different diamater disks on the shaft where it engages the wheels to get in the speed range you want. The speed is also ajustable by using different pully sizes leading up to that shaft.

You need to keep the belts tight so they don't wear. So the distance between the shafts has to be constant. The output shaft has to swing in an arc around the the previous shaft in the drive train when it engages/disengages. For the valve tie a linkage between the structure for these shafts to the valve so as the output shaft swings into the tire it turns on your spray valve.

Not that good of a description, I know... I'll see if I can find or draw up something that gets the idea across better.

lets talk ok....dont go !

I live in PAKISTAN DUDE ! And am doing mechanical engineering !

Ok but why should i use belts ? why not use chains.... like those bicycle chains ?

And i know pretty well about gear ratios but im thinkiung why slide a shaft for engaging and disengaging.... why not just turn on and off the motor when required.....

You can paint without moving???

PAKISTAN DUDE... I asked to more understand your resources... That's all...

why not use chains.... like those bicycle chains ?

And i know pretty well about gear ratios but im thinkiung why slide a shaft for engaging and disengaging.... why not just turn on and off the motor when required.....

Chains are fine as well as long as you have another way to regulate your speed if need be.

2 reasons to disengage it. So it can be easily pushed when not powered (and easier to stear when disengaged), it is safer for stopping and starting. It will also make it harder to start the motor with tires engaged.

The shaft before the drive shaft is your pivot. The arm with the drive shaft swings down and presses onto the wheels. The linkage to handle this also locks the drive shaft aginst the wheels.

I'll post a picture or sketch in a bit.

Dale

OK a quick sketch of waht I was talking about. For the sprayer valve just add linkage to turn it on/off as well.

Man your sketch is really a life saver.... i really appriciate it, you taking off the time to actually make a sketch and then upload... thank you thank you thank you !

Hey Faisal,
Hows this paint machine coming along? Haven't heard much latly?
M