Raspberry Pi trail signs

I think this is a very good project and as a biker and runner i am also interested to see how can u make this possible.

Dont be afraid of the microcontrollers. I started with the Raspberry Pi two and half years ago but now i started using and learning about micro controllers.

You can find plenty of code from the community.

I too would agree with Paul on this one, The Arduino Approach, the complete basic controller and sensor could be built for a few dollars (Pounds) where as the PI is $35 before you even do anything including adding power so I doubt you would get much less than say 100$ for a PI based solution, rather than way less than 50 for an Aruduino (More specifically an ATMEGA328 or cheaper chip), even an arduino may be overkill for this but still cheap enough and would be way less power consumption giving more night time running

Don't forget horses.  I used to bike on a Northern Virginia paved trail shared between pedestrians, runners, bicyclists, and horses.  It generally worked well, since bicyclists had to stay alert for hazards, including the occasional snake crossing the trail.

One day I was surprised to see a riderless horse coming my way.  I managed to stop, set up my bike, and grab the horse's reins and stop it (it wasn't moving very fast).  I stood there wondering what to do next for a couple minutes when a girl on a horse arrived and thanked me profusely for catching the riderless horse.  The girl's friend showed up a little later, limping from having been thrown.

In the name of all noobs in the world, thank you guys...

I must to say that I learn a lot reading this set of answers

Dangerous things these horses!

It should be mandatory for them to be fitted with handbrakes.

Yes, we are talking about dirt paths, but because we are a little pressed for space, our paths are in towns, behind the scenes if you will. You couldn't have addressed the problem more perfectly. We have dedicated mountain bike trails, however most people just decide to go wherever, or don't realize the danger, hence, the signs. I don't want these serene trails covered with electronics either, but if that's what it takes to keep people safe, then what else can we do? Maybe that's why we americans hold the citizens of the UK in such high respect.

Yes, solar seems to be the best solution, or, since there are houses right along our trails, a nice neighbor might let us plug in. About the Arduino, suggestion noted. I haven't had much experience with them, so I wouldn't have known.

Thank you so much for your support! I am a middle schooler trying to get my "school of the arts" associated with Raspberry Pi and other units like it. Support from you and others is helping me make leaps in this direction. In all honesty, I have only been working with this technology for a matter of months, but such support is willing me to go farther and farther in this amazing world of electronics. Thank you everyone!

I think Arduino will suit you perfectly. It might look daunting, but you'll have a simple sketch up and running in absolutely no time at all.

The cost will be more attractive and you will be amazed at the speed of development when you get going.