Bi-Directional switch and a 555 timer

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Hi Everyone,
I would really appreciate some help. I want to build a floating feeder for a large fish pond. The floating platform will be secured by a tight cable line from one side of a pond to the other. The floating platform will have a geared motor (12V) on it and the cable line will be wound around a shaft connected to the geared motor so it can ‘tow’ itself across the pond on the line.

My predicament is getting it to change direction at each end.
I have a design in mind, but am happy for suggestions.
The line will have a ‘stop’ point at each end, and the feeder will contact that. When the stop is hit, this will change the direction on a bi-directional switch, so the motor changes polarity and goes back the other way. But I don’t want the motor to restart immediately.

The reason for the delay is to let the momentum of the floating platform be removed through the line when it hits the ‘stop’ point. I think that if the floating platform is moving in one direction and then the polarity switches in the motor and the motor immediately goes the other direction, it will be fighting against the momentum. So I want the motor to stay off for 10 seconds. When the floating platform hits the ‘stop’ point the momentum is lost, then when the motor restarts, the floating platform is starting from a standstill.

I think that a 555 timer would be suited, but I am just not quite up to speed with circuit design to get myself to this point.
The motor I am using will probably be about 1 A and 12 volt.

I would really appreciate thoughts, redesign suggestions and any assistance with the circuit.

Thanks

2

Hi @BigKiwi,

Sounds like a great project underway. While a 555 timer might be possible, I personally would lean to a programmable chip.

With a few lines of code, you could have this entire project working the way you need. It would also enable little tweaks here and there (X seconds for that, Y seconds for something else).

If this interests you, but you are new to digital electronics, then perhaps take a look at a starter kit such as the one below. Once you know the ropes, you could use this kit to prototype an idea and then buy the single chip for around $3 for use in the final project (along with the other bits specific to the project).

No matter what pathway you take, you’ll be up for some DIY. Learning how to program a microcontroller will position you with handy skills to tackle everyday problems.