Meet Dave

Here's Dave I would like to introduce Dave to you. No, Dave is not a space ship in the shape of Eddy Murphy, which came to earth to steel the salt out of our oceans. Go and see the film "Meet Dave " if you don't know what I'm talking about. I liked that film, I hope you'll like it too. If you're into not too serious Sci-fi I'm sure you will.

The Dave I'm introducing to you is one of my minions. All my computers are named after a cartoon character. I thought I'd be appropriate to name my Raspberry Pi computers after the minions from Despicable Me. Hence, the name Dave.
I'm thinking about deploying many more Raspberry Pis around the house, for various purposes. Fortunately there are plenty of minion names to choose from. My Pi-SB-Bus Driver is named after Stuart now, by the way.

For the time being Dave is an ongoing project. It is functional, but far from finished. There are many more tasks I'm going to assign to him. Some tasks Dave can perform already are very crude and have to be refined before I'm satisfied. The main thing is that the tasks are performed now, even when they are quick and dirty.

Dave's Current Tasks

Dave has taken over most of Bambam's tasks now. Bambam used to be my main home server. Basically Bambam was a desktop computer and it was also used as such on my work bench. Because it had to do lots of other services I've kept it running 24/7 for quite some years. Well, in fact there were 3 Bambams over the years, as the older ones were replaced by a newer machine. However such a desktop computer is rather power hungry and costs about €140 on electricity per year. A Raspberry Pi is satisfied with just a small fraction of that. Dave may not be as fast as Bambam was, but he gets the job done. He's got 24 hours a day to finish his jobs anyway. And he still has lots of time to spare, so there's plenty of time left for him to pick his nose.

Currently Dave has been given the following tasks:

  • Be educational. This is probably Dave's main task. I may have passed the age of 50 quite a few years ago, I'm still keen to learn.
  • Web server. Serving my landing page, the page I tend to use on all my computers as main index page containing the links to my most often used web sites. In the future this web server can also serve up the various applications I hope to create.
  • ssh access/tunneling. Dave is also my main gate keeper. Through Dave I can reach my entire network from anywhere in the world. Dave is not very fast, but who cares, the internet in my area is the slowest link in the chain for sure.
  • Database server. Dave has got plenty of disk memory to spare to remember quite a few things for me. This information is stored in some MySql databases and is instantly available in my network and on the internet if I want to.
  • Reminder service Dave keeps me updated on important occurrences. Normally he does that through email. If the situation is bit more urgent he can also send a text message to my mobile phone.
  • Monitoring Dave monitors some web sites for me. Some of them are my own to make sure my sites are not defaced by hackers for instance. Other web sites are monitored to alert me of new content, which might interest me.
  • Domotics Dave can control some of the lights in my house. He does this in a quick and dirty way at the moment. I'll have to teach him some more tricks to be able to control more lights. But hey, it's a start.

These are not all the tasks Bambam used to perform. Since Dave's brother Stuart, the Pi SB-Bus driver, is also running 24/7, I have shared some of Bambam's previous tasks between Dave and Stuart. For instance the more time consuming backup services are performed by Stuart. This prevents slow responses from the web server while backups are being made.

Dave's Future Tasks

This all depends on the time and effort I can put into it all. But one of the main tasks would be controlling some lights and devices in the house. Either automatically or by remote control using a self made app for my mobile phone.
It's not my intention to automate everything and anything in the house. I probably never will automate closing the curtains for instance. It will cost me much more time to develop than I ever can earn back in the remaining part of my life. I'm not going to automate my coffee machine either, as we both don't drink coffee.

Controlling the lights can be done in a few different ways. One way is by the built in relays. Dave has got 3 of them. It also has the outputs to control 4 more, giving a total of 7 directly controllable mains outputs. Not only can it switch lights, it can also switch my Wifi access point off when I know for sure that I don't need it. It can also control the water pump of my central heating during the summer months. Switching such a pump off for months on end is not a very good idea. You can count on it that it won't start up again when winter comes. But if you turn the pump on for about 15 minutes a day it will most likely survive the summer. With lower energy costs and less wear on the pump itself.

Another way of controlling lights and devices would be by 434MHz radio control. I own 6 of those very cheap switches for ages and I use them on a daily basis. Dave has got a built in 434MHz transmitter and receiver, which would enable him to listen to commands from the remote control and to control the lights and devices himself.

Many USB devices exist which can control even more devices around the house. Not that I intend to start using any of them soon, but who knows, when I run out of other ideas to implement.

I may call in the help of some other minions in the house or garden shed to control devices located there. That may decentralize the control, reducing the number of wires running across the house.

My sunscreen is also controlled by a 434MHz radio remote control. Dave might be able to control that as well in the near future.

Dave can also monitor lots of temperatures through its one-wire interface. I could start logging temperatures around the house. He is standing on top of an extra refrigerator and a freezer in the garage. It'll be quite easy to monitor their internal temperatures.
We tend to forget to close the freezer's door occasionally. This has already happened twice, only to be noticed far too late of course. Dave can warn us when he realizes that the temperature gets too high.
We also tend to knock the thermostat knob of the refrigerator all the way to maximum. Needless to say that this will waste a lot of energy. And here Dave can come to the rescue again, informing us of the extreme cold temperatures in the refrigerator.

I have only skimmed the surface of what other tasks Dave may be able to perform, if time permits it.