Stop Light Mechanism

[Hammad J]

Hello Peoples. I am pretty new here and new to all this circuitry stuff. I am in a competition and I have to build a Stoplight Mechanism (basically a traffic light). I need to know how i can build it WITHOUT using electronic timer chips or any of the sort. Attached here is a PDF of the rules. I need help, I am Totally lost.

P.S. I am only in Grade 9 and the price must not exceed $24.99

 

[blueroomelectronics]

Why did you start the same thread twice?

 

[Hammad J]

Because no one replied to my other thread. =(

 

[Hayato]

I did not see a paragraph forbidding you to use timer chips.

I've never seen any traffic lights without timing.

 

[Hammad J]

"The distribution of power to the lights and the timing mechanisms are
to be mechanical or electro-mechanical in nature, essentially excluding any
electronics or lC timing chips"

See that?

 

[Hayato]

Hmm. So you need to use some sort of electro-mechanical timer.

Or just use electro-mechanical switches to make logical gates.

 

[Hammad J]

Could you please explain?

 

[Hayato]

You are going to build logic gates based on RTL logic, but using relays or switches.

For the electromechanical timer, you could use a motor driving a cam that keep poking a switch, each time the cam pokes the switch you gonna have 1 time unit that can change the stoplight state.

 

[Hammad J]

Uhm, The total cost must be less than $25, and im only in grade 9. I dodnt understand half the stuff you said. Could i possibly be able to use a kitchen timer in some waY?

 

[Hayato]

The thing is, you didn't understand? Or you don't want to understand? 'Half' is a big universe, be more specific on what you did not understand.

'Who enters the mud, wants to get dirty.' This is not a 9th grade problem, probably you are doing some kind of technical school, what is the course/subject that you are doing?

Look for RTL logic at google, you can do logic gates using relays and resistors.

Yes, you can disassemble a kitchen timer and build some sort of mechanical timer there.

 

[blueroomelectronics]

You could do it with cams, roller switches & a motor

 

[Mike_2545]

Like I had told him in his first thread about this... https://www.electro-tech-online.com/threads/stop-light-mechanism.102636/

 

[Hammad J]

That doesn't work for me, its too advanced and exceeds the price limits. This is a science Olympics Competition im competing in. It is something Extra-Curricular

 

[Hayato]

Adding a cam to a kitchen timer is not advanced at all.

 

[blueroomelectronics]

A three cams on a single axle and three switches could do the job, doesn't get much simpler than that.

 

[Hammad J]

The problem is not building it, but accessing the materials. What I was thinking is that a toy train that travels around a toy track. The track would have an open circuit on it. as the train crosses, it closes the circuit, thus turning the light on. The timing will be judged based on the length of the open circuit on the track. need ideas like these. Thanks for your help, I appreciate it alot.