Feasibility of using Arduino for timer project and would anyone build it for me?

Some time ago I bought some components with a view to trying to build a timer/warning device so that a boat driver can monitor session times on the water. To be honest I neither have the time or, as quickly became apparent, the expertise, to do it :~ So I am posting on this forum in the hope that somebody may be interested in either taking on the project, or is able to put me in touch with someone who might. I would be happy pay a reasonable amount for somebody's time and expertise, and of course the components. Alternatively I am could trade some wakeboarding or waterski lessons for it :P . If just the components could be put together to make a functioning circuit, I can get the whole thing put into a suitable box. If it can be built successfully, I will actually need two. I have been told that it should not be difficult but it is certainly beyond my capabilities. I am in the UK.

The device needs to have a countdown timer, with a display for the driver to see. It needs to trigger an audio and visual warning when getting close to a fifteen minute time limit and, when the time is up, to reset itself. It also needs to switch a fairly bright light which which will reflect these actions and can be seen from behind the boat . It was suggested that this could be based on an ARDUINO board. It would draw its power from the boat's 12v system.

The sequence would be as follows:

Timer is started by driver The digital timer display starts to countdown from 15 mins in seconds The boat driver will see from the display that the timer is running. A light bright enough to be visible to a person 20m behind the boat is illuminated so he/she also knows the timer is running. At 12 minutes, the driver gets a visual warning, maybe the display flashes, perhaps once per second. The person behind the boat also gets same warning on their light. i.e. flashing once per second. At 13 minutes 30 secs, the display flashes more rapidly and a buzzer also sounds for 10 secs. indicating to the driver that the time is almost up. The person behind the boat also gets the same warning on his light (i.e. rapid flashing) (may want to incorporate an audible warning too, loud enough for them to hear). At zero, the timer automatically resets itself to 15 minutes and restarts. At this point the driver has the option to allow it to continue running without interruption for the next 15 minute period and so on, or he can stop the timer manually, when it will simply reset to 15 minutes and become idle until started again. N.B. A facility which allows the timings to be customized would be very useful (presumably this could be done by changing the Arduino code?)

So thats it. Simples! (apparently)

If you think you can help me with this and I will be delighted to hear from you. Many thanks Mike mirlyn

Posts: 1 Joined: Thu Dec 12, 2013 5:08 pm

The coding is relatively simple. The hardware choices are not well defined.

The device needs to have a countdown timer

The device IS a countdown timer...

with a display for the driver to see.

Servos waving flags? What kind of display? How big? How bright?

It needs to trigger an audio and visual warning when getting close to a fifteen minute time limit and, when the time is up, to reset itself.

The first part makes sense. The second part does not. At the end of the timed interval, just start over, after panicking that the driver didn't stop?

It also needs to switch a fairly bright light

I checked Mouser. They didn't have any "fairly bright light"s. Perhaps you need to quantify this.

and can be seen from behind the boat .

This requirement needs some explanation. Who/what that is not ON the boat cares?

Timer is started by driver

How does it get stopped?

The person behind the boat also gets same warning on their light. i.e. flashing once per second.

On their light? Where did this requirement come from?

and a buzzer also sounds for 10 secs.

More new hardware requirements (that are not well defined).

Be aware that automotive electrical systems are noisy, and play all kinds of havoc with electronic devices. I'm not sure about boats, but I don't suspect that the environment is any better.

A board with several relays to provide contacts for the lights, horn/siren, etc is pretty simple. A 4-digit 7-segment display is also easy to add, you'd need to make a decision on what size digits. For example: http://www.kingbrightusa.com/category.asp?catalog%5Fname=LED&category%5Fname=KC1%2DDigit+1%2E8in&Page=1

Buttons as needed for the reset, time adjustment (up, down, set) are also easy to add. Put the whole thing in a watertight case from www.polycase.com with watertight cable connectors for the various things to be controlled. http://www.polycase.com/wc-series

Use a switching regulator to supply power to deal with the potentially dirty power supply. http://www.pololu.com/product/2107 Maybe 2 of these, one for the display current, one for everything else.

You could indeed use a light + pattern to tell the person behind the boat how "late" it is, but why not use 2 displays counting down seconds ?

You wouldn't need to remember/ watch for the change of the pattern, 1 glance would instantly tell you how many seconds are left.

Using high luminosity leds, a display like... this http://www.bakatronics.com/shop/item.aspx?itemid=591 is probably readable up to 40 meter, not hard to build (and probably a lot cheaper as in the advertisement).

Enclosure? NEMA rated (or whatever the modern equivalent is)?

It needs to trigger an audio...

Does the annunciator have to be weather-proof?

It would draw its power from the boat's 12v system.

A power failure and resumption causes the device to do what? Continue where it left off? Start over? Alarm immediately?