Lone Worker

Hi all!!

I'm new to arduino but have had fun messing around with it recently and have found the hardware side easy, with the software and sketches kept simple I'm able to create some cool stuff.

Time for a serious project.......

I want to develop an arduino project to send out an email or two based on a couple of variables, sounds simple but it gets more complicated. Basically I want to install a system in an 11kv high voltage transformer room whereby when a user walks into the room they press a button to announce their arrival. The system then counts down from a predefined time and then it goes into prealert mode which will flash some lights and maybe use a buzzer, if the user doesn't press the same button again to restart the countdown then the arduino will automatically send out an email (or load a webpage elsewhere on the net which will automatically send the email if easier) to alert others of their failure to press the button again and in effect to declare themselves safe. In practise this means that if the user has not pressed the button to declare themselves safe then an alert will be sent out for someone to check on their welfare. When the user exits the room they will press a 'Safe' button which will stop the countdown and stop any alerts.

Additionally I would like to use a PIR sensor to monitor the room also and if the user fails to press the start button on entry then an alert will go out via email to warn that someone is not using the system correctly or possibly an unauthorised person is using the room.

Other future uses for the PIR might also include the possibility of including in the alert email that motion has or has not been detected on alert which may signify that the person has had an accident and could be unconscious.

As I said before I'm perfectly ok with the hardware side of this, I'm just a bit miffed on the software side, so any possible help would be appreciated

Many thanks in advance! Steve

I'm not much of a programmer, I only started with Arduino about one year ago. I had never written a line of code before that. I would buy all the parts and then play with them one by one. Write sketches for every sensor separately. Then try to integrate all the sketches in to one sketch step by step. Take little steps, and if you have some trouble post your code on here. People have always helped me here when I was stuck :) It's a good idea to write down what you exactly want to do, like a flow or block diagram. And use that as a reference to write your code.

Interesting project!

I was a Broadcast Engineer for 16 years, working with High Voltage that killed one or two Engineers a year back in the 1960's..

My Dad was Chief Engineer of WELI and has survived to 100 years old. He had two rules: (1) NEVER Work alone with the transmitter cabinet doors open. (2) Opening any transmitter cabinet door turned off the High Voltage, but an emergency override could turn the HV back on AND several big flashing red lights.

You are sort of duplicating that situation, with the second person being remote. Think about the red lights, though.

I agree about the "Stepwise Refinement" approach. Get all the pieces working elsewhere first.

OTHER: There are large electrostatic and magnetic fields in the area of 11Kv. You should think "Grounded Metal Box" that contains your circuitry.

Let us know how this progresses....

I like your idea of the PIR sensor and I think with some logic and a IR tripwire sensor and a magnetic sensor on the door you may be able to have an autonomous system.

The order in which the tripwire and the door magnetic sensors are triggered could determine whether a person entered the room or left and the PIR sensor could tell you if there was movement in the room. If there was no movement for a period of time and there was a person in the room an alarm would be triggered. The benefit of the no movement indicator causing an alarm would give you a better response time if measured between the time someone had an external electrical caused heart attack and when someone brought in some basic life support. We installed some sensitive PIR in a secure room that would get triggered by mice running on the floor so they can pickup minor motion from a human.

Just some thoughts and I believe there are some holes in the above that can be filled in to create a functional system, but then aagain I may well have missed the boat entirely.

sensitive PIR in a secure room that would get triggered by mice running on the floor

...sounds about as secure as my workshop :0

Time of the season to bring out the Victor Peanut Butter Dispensers.

Are there exposed HV conductors? What is wrong with having a physical barrier to prevent the person approaching the conductor by less than the safe distance? If the person did come in contact with HV how long do you think it would be before your system raised the alarm, how long would it be before help arrived, and would this be likely to have a significant impact on the outcome?

The problem is this, on occasion, when servicing equiptment you might have reason to test something with power applied. This would not be a normal condition, but would be the exception. I also work as a broadcast engineer and there are hazardous voltages present in areas that need to be accessed for service. Our transmitters have a high voltage of 36KV and 32KV (at about 2 Amps) Under all normal conditions this is well protected from contact, But on an older transmitter that was removed from service there are a whole lot more opportunities to stick an appendage somewhere where one shouldn't. You know there is a possibility for danger when attached to the front of the cabinet is a grounding stick to discharge the large Capacitors and such.

Now a days in broadcasting, the number of staff available to work on stuff is usually yourself. Gone are the days of large staffs and large budgts as this is an industry that has a lot of competition and thus you sometimes have to do things under less than ideal conditions.

Even better would be a webcam on the cage so someone could observe the person working in the hazardous area. Call the security desk and let them know you are enterring the area, and once again when you leave so they know when to keep an eye on things.