Electronics project. proximity detector

[Nath.Win]

HI
This is one of my 1st post's so bare with me.
Basically i have a problem, i have a few weeks to make a simply proximity sensor for my AS electronics.
It has to be as simply as possible, and be on a single unit. not one of those broken been IR kind of things.
I have found a link with a video that shows the what i would like to create. but i dont know how to create it, and as i cannot use PIC or any other chips. just 555 timers etc.and i have to make it all myself.... i am unsure of how to do so.

Any help would be greatfully appreciated. o and it has to run off 12v s max.




Here s the link to the video

**broken link removed**

 

[Torben]

Hi Nathan,

The user's manual on the page you linked to contains a schematic of the device. You could just build your own from that; it's a simple circuit.


Regards,

Torben

 

[Nath.Win]

Does this not use some kind of programmed chip? or controller..
I am in my 1st year and have not been taught the subject matter involving PIC's or any programming. Therefore this would meen if i was to create a project that incorporates this that would arise suspicion...
I can only use more low level components...
Thanks

 

[Mikebits]

Does this not use some kind of programmed chip? or controller..
I am in my 1st year and have not been taught the subject matter involving PIC's or any programming. Therefore this would meen if i was to create a project that incorporates this that would arise suspicion...
I can only use more low level components...
Thanks

Buy you books and send ya to school and what good does it do?

Think my man. How would a proximty detector work? Sound travels at x speed per second so first thing is to find the number for x. Second, how do we create the source for the sound emitter, third how do we measure sound emission to sound reception?

Create emitter, measure time using, I dunno counters maybe, then when X arrives, we have a number.

I worked on a old ancient SPA-25 radar system that could do this without microcontoller chips. It was actually many transistors which made up counters mostly.

If you think about it, you can logically approach this problem. Do this, make a block diagram of what you think you need, then post your question, otherwise your on your own...

 

[jpanhalt]

What do you want to detect and at what distance?

There are a lot of possibilities, such as inductance, capacitance, sound (up to MHz), and light. Each method has its own characteristics.

John

 

[Nath.Win]

ok. i wouldn't know iv been studying electronics for 9 months just basic s at the minute...
ok so the scenario iv been given is "your in a car park.. you have a new car and you don't want it scratched or dented.. you cant prevent this but how u can make people think twice"
i came up with an idea of using LDR's but a light dependent resistor would n work in a dark car park or with head lights keep goin past... so when a car is reversing into the space next to the car.. i want it to detect the movement of that or the door opening, and flash a LED placed in the window and sound like a car horn sound...
That is the basic outcome.. but i dont know how to make something to do it....
any help?

sorry for the basic's here but at the minute were being taught logic circuits and amplifiers... 555 timers that kind of thing.. so i don't know alot!

Thanks alot

 

[jpanhalt]

ok so the scenario iv been given is "your in a car park.. you have a new car and you don't want it scratched or dented.. you cant prevent this but how u can make people think twice"

And you think an alarm -- particularly an alarm that goes off when someone starts to open a door -- will do that? I suspect the effect would be the opposite.

Ask your instructor for a problem that is more appropriate for your level of training and has a realistic solution. Or to put that another way, would you hire someone whose education was rooted in learning how to design things that would not work?

At the very least, you need to decide whether you want to detect any movement, including people, or just metallic objects. You need to define what you mean by close. Is too close 10 ft, 10 inches, or 1 inch? How would an alarm that goes off after the fact deter anyone from opening their door into your car?

John

 

[Nath.Win]

I think the idea is before some one does. like there car is close in England anyway. parking spaces are tiny. so as soon as a car reverses next to you (about 2 foot away) there is of how ever long it normally takes to reverse and then open a door and the car will beep... or as soon as the door comes within a foot there is a beep. that kind of idea... there is a link above the the kind of idea im looking at but its just too complicated as i cannot use any kind of programmed chip.

 

[Torben]

Does this not use some kind of programmed chip? or controller..
I am in my 1st year and have not been taught the subject matter involving PIC's or any programming. Therefore this would meen if i was to create a project that incorporates this that would arise suspicion...
I can only use more low level components...
Thanks

No, it doesn't. If you look at the schematic you'll see that the only chip is a 74HC00, which is a quad 2-input NAND gate. They cost less than a dollar and do not need to be programmed.

Hint: if you see a part number which you don't recognize--especially on simpler or more recent designs, you can usually put it into Google (might help to add the word 'datasheet' as a search term too) to find information on what it is and what it does.

That said, I believe that ultrasonics are more frequently used for vehicle collision detection systems.


Good luck!

Torben

 

[Nath.Win]

Brilliant thanks.
I will run through this tomo with my teacher n post the outcome.
Thanks alot