Sebastien St-Laurent's (AKA Sebby) WebLog : Home Automation

Moving my Main Blog From MSDN to WWW.SebbyLive.Com

sebby1234 — Fri, 05 Oct 2007 06:06:00 GMT

The time has come to finally move away from hosting my blog on MSDN. There are a few reasons for this transition but the two main deciding factors were that posting personal posts on a MSDN blog seemed odd (at least to me) and that I already had my own website to document my various side-projects so it would make more sense to have everything in a single place.

My blog now resides with my homepage at www.SebbyLive.com. In the future I may cross-post relevant technical posts onto MSDN but you should update your feeds to point to the new "main" blog...

The syndication link which can be used to subscribe to my blog directly is: http://www.sebbylive.com/syndication.axd

Surface Computing... Neat-O...

sebby1234 — Thu, 31 May 2007 00:24:00 GMT

Popular Meechanics got a sneak peak of Microsoft Research's Surface Computing Technology.

This is really cool technology. Not usefull for all applications but I can see a few things for which this would be useful!! :)

The Tahoe Devkit is In!

sebby1234 — Mon, 14 May 2007 18:30:00 GMT

After a long wait, my "Tahoe" dev kit has finally come in a few days ago.

Comes in a nice little case, with everything needed to get started. The CD does contain a CD with a wide variety of samples. I have not had a chance to play with it yet, but the first things I need to determine are:

LCD Support: What is the built-in driver and what type of screen it can accomodate. Although the 2.5" screen that comes with the board is nice, I would prefer something in the 4-5" range with touchscreen support for my application.
Ethernet Support: The kit does not have support for this "out of the box" but there are several add-on modules which can do this using the I2C or SPI ports. I need to locate what is the best option for my application
User Interface: The .NET Micro Framework does support basic graphical capabilities, but I may need a higher-level system to tie it all together.
User Input: I have recieved samples of the capacitive touch sensors. However, to test them, I need to create a PCB. At this point, I am unsure whether or not I will wait for my CNC to be ready or simply have a few test boards pre-fabbed so I can start working on it.

Quick Project Update.

sebby1234 — Sun, 06 May 2007 20:35:00 GMT

Had a few emails asking abouy my various projects. Thought a little update would be warranted. The short answer is that not much has happened since my last post. But here is an overview of the individual projects:

CNC Mill: Still waiting on the motor controller board. Since this is the key component that ties everything together, I cannot make much progress until I get this part. It has shipped from the UK but since they have shipped it parcel post, I am unsure exactly when it will come in. I have contacted them about this and they say that based on when it was shipped, I should get it early this week. *keeping fingers crossed*
Home Automation: I am still waiting on the "Thaoe" development board before I can start experienting with the electronics. Also, since I want to use the CNC Mill to engineer the circuit boards and panels, I cannot make much progress on this front.
Cell Phone / Smartphone: Little progress on this front. I have mainly read the documentation on the GSM/GPS module and really need to start playing with it. Although my overall design goal is to create a UMPC/Smartphone hybrid; I am thinking of starting off with a more basic cell phone design for me to experiment and concentrate on the core functionality of the cell phone.

So overall, most projects are dependant on the CNC Mill project, not just for my little projects but for some of the renovation projects around the house. At least I do have all the main parts and most of the work needed will be to put the pieces together and build a frame for the machine.

With my finger still in a splint, it is hard yo get any significant manual labor done. Even typing is somewhat difficult. On the bring side, the splint does come off on tuesday so I should be a little more "mobile"...

The One-Haned Post... :)

sebby1234 — Mon, 30 Apr 2007 20:30:00 GMT

No, nothing twisted. Just still have my splint on my right hand so I almost have to type using a single hand :) Its been a while since i've posted a general update. So I thought today would be as good a day as any...

Health

Last week has been pretty bad health wise. If you factor in my finger surgery and the fact that my IBS has returned full-force. It has been somewhat of a "crappy" (pun intended) week.

My finger isn't doing bad. But the splint has caused my to overcompensate and now my wrist hurts... Hehe. Guess I should have not been using that hand but then again I had work and other things to do.

For the digestive issues, well at least now that it's back full-force this means I am officially off the clinical trial I have been on. With the addition of a little $300 check, I now know the medecine which they are investigating (although not FDA approved for this use) so I can try and bug my Dr. to get a prescription for a full treatment (since I am not even sure if I ever got any meds).

My bipolar has been doing pretty well over the past week, especially considering all the other health issues that have been going on. Tomorrow, I will cut my anti-depressants in half again (i.e going from 10mg to 5mg of Lexapro). The reduction so far seems to have made my mood less volatile. So hopefully by cutting off completely, I will finally even out (or at least be a little more predictable).

Home Projects

Not much has happened on this front. At this point, I am mainly waiting on parts to come in. Hopefuly I will be able to start playing with some of the components later this week and will start making some progress on my CNC Mill project. Since my last post, I have recieved the actuall router for the mill and the Z-axis slide for the router, the main component that is missing at this point is the controller board for the step motors, which is what I really need to start hooking things together...

The only other things that will be missing is what I need to build a frame, but I am still debating which material to use, on one hand wood would be cheap and easy but I worry that it will warp over time. The ideal solution would be an extruded aluminium frame but these are more expensive, especially for Version 1.0 of my mill :)

In the meantime, I am focusing mostly on household projects such as cleaning and painting, nothing too exciting there :) I've also kept my eBay garage sale going. Books are selling really well and i'm probably about 30-40% through my inventory. This should really help clear up some garage space. And I have been using the proceeds to partially pay off some debts and finance my other home projects.

Publishing

Just recieved the proof for the second edition of Practical .NET 2 and C#2. I am going through it this week and gathering the funds needed for the print run. The book should be fresh out of the printer by the end of May and with a little luck, on bookshelves around July. As a side note, I will be offering an "upgrade" program for those who already purchased the first edition and want to get the new revised edition. I also plan on having the new edition for sale at a special launch price before it officially hits the shelves... I have two other books in the works at the moment. One relates to VS 2005 express however the author has been MIA for the past few months and with the upcoming release of Orca, the title might be delayed so it can be updated for the new release. The other title is related to Ruby on Rails, we are a little behind schedule on the translation (my hand surgery isn't helping there!) but hope to have this title out by the end of the summer.

Work

Work is going well. The Flight Simulator service pack is almost out the door and I have been busy mostly helping fix a last few pending bugs. Of course, this week, it is really hard to be efficient typing with 1 1/2 hand. But I do the best I can...

Currently, I am still on part-time work but will be ramping up my schedule and will be back full time at the end of May. Hopefuly by ramping up I can get my sleep/work balance back to normal and be more energetic on a daily basis (of course, some sunshine outside would help!!)

CNC Mill Components Comming In...

sebby1234 — Sat, 28 Apr 2007 06:01:00 GMT

Some of my components have finally started comming in. So far I have recieved my motors, linear actuators and power supply. Unfortunately, i'm still missing the controller board (which is shipping from the UK) before I can really start putting anything together.

In the meantime, I have been looking at software options to run the mill. I have not been able to find a decent opensource or low cost option out there. The best cost/feature option I have found so far is Mach 3. Not too bad for $159, considering some of the other options out there are in the thousands of dollar. Who knows, maybe someday i'll write my own software. But I think I have enough projects on my plate for now :)

My only other worry so far is in regards to the linear actuators I have purchased. They use a timing belt and have a decent precision. This was the only option I could find within a reasonable price range. The ideal would be the use of a ball screw system (which is a combination of a high precision screw and a ballbearing nut). But the drawback is that these are really expensive. From the prices i've seen so far, a 2' rail can easily cost $300+

Since the motor controller board supports microstepping, that should give me about 0.0006" precision with my current actuators, which I think should be sufficent.

Creating the Circuit Boards for My Projects

sebby1234 — Sun, 22 Apr 2007 09:04:00 GMT

With all my new projects, I need a way to produce the PCBs (Printed Circuit Boards) for the electronics.

The classic homebrew approach involves the use of a etch resistant transfer to the board and the use of an etchant solution (here is an example which uses transfer from laser printer toner). The main problems with this approach is that it is of limited precision due to the etching process and I am not keen on playing around with these chemicals unless I need to (not like I have enough health problems anyways) :)

A second approach is to make use of a PCB prototyping company (such as ExpressPCB). The pros to such an approach is that the will provide boards with solder masks and even silk screen. The drawback, is the pricing (although reasonable), can still be quite high at $30/board. In addition although they have a quick turnaround, you still have to wait at least a few days to get your boards.

Another interesting approach that i've seen is the uses of a CNC mill to essentially route a PCB. Below is a clip from YouTube.com showing how a CNC mill can be used to create a PCB. Notice how the mill essentially takes out the coper around the traces, which is somewhat the reverse process which happens with regular processes. You could have the mill take out the excess copper elsewhere but it would take longer. And then in general, you can also use this copper as a ground plane.

The one interesting thing with the idea of a CNC mill, is that it can also be used to do woodwork and other projects (some of them would be cool for around the house). Unfortunately, a commercial CNC mill of a reasonable size is in the $5000+ range. Didn't I mention that I was broke :)

So, now what? Well looking at those, their construction seems straightforward. So I smell another project coming on. Did some research and I should be able to construct one which meets my needs for under $1000. Surprisingly, you would think the most expensive part would be the motors and controllers. But the expensive parts appear to be the aluminum framing for the mill and the ball screws and slides (to convert the motor rotation into a linear motion). $200 for a 6ft screw? Ouch!!

Of course getting pricing on some components have been hard, most manufacturers don't list their prices. I've only found a few places online where I can get some pricing info...

User Input For Home Automation

sebby1234 — Sat, 21 Apr 2007 22:03:00 GMT

Besides the touchscreen, I wish to use buttons to control a few other components of the system (such as the intercom buttons) and maybe a numeric keypad. The obvious (and easy) solution is to use standard buttons. There is of course several options and variety for those. But I was also curious how other devices (such as some of the IPODs and even laptop mousepads worked.

After a little research, most of these devices uses a form of capacitive sensing to detect contact (or proximity) of a grounded object such as a finger. Below is a little disgram which illustrates how they work.

The finger (or other grounded material) essentially drains up some of the field between the two electrodes, which is detected by the chip and considered as a button press once the change reaches a certain level. This diagram is taken from the documentation of the Analog Digital AD7142, which is a 14 channel capacitive sensor chip.

The AD7142, has 14 channels which allows for the implementation of over 36 buttons, more than what I need for my application... In large quantities, the chip goes for under $2.00 per unit, which is a good price. The main drawback for me is that it is a surface mount component (but then again most chips are these days) but for now I have ordered two sample units from Analog Devices so it will give me something to tinker with. So I will have to start learning and experimenting about homebrew surface mount techniques.

Another design consideration here is that there must not be an air gap between the sensor PCB board and the device cover as air has a tendancy to dissipate the field and therefore reduces the sensor's sensitivity.

Misc Update for 04/16... Well 04/17...

sebby1234 — Tue, 17 Apr 2007 10:48:00 GMT

Near 1 am, getting tired. So it is indeed time to go to bed. But since I havn't posted in a few days, I thought I would post a quick update.

House Life

Actually started working more on the house with my wife. Not that we hadn't been doing anything before but most of it was planning. We've actually started painting this week. Don't like painting that much, especially when the walls are textured but we just have to get rid of those bland white walls! Not too easy decorating a new house when you're flat-broke.

Just not funny how this whole double mortgage thing left us in a pretty deep sink-hole. Feels like every time you manage to crawl back up a little, something comes along draining your accounts over again. Essentially had to borrow against my 401K to maintain cashflow. This of course isn't really good and is only intended as a bandaid until things settle down.

Anyways, we've been trying to keep the renovations as cheap as possible. It's amazing what you can do with a gallon of "oops" paint (at $5/gal instead of $25/gal) if you're not too specific about colors. :)

My Health

My health is pretty much the same as it was. Still plagued by some ups and downs. I am seeing my psy tomorrow and he will probably adjust my meds again. Hopefuly, this will make things better over the next few weeks. Although I do feel better overall than I did a few months ago, my energy levels and mood tend to shift alot doring the day. Which makes it hard on some days to stick to a schedule or game plan.

Besides that, I have a lump on one of my right hand fingers. Had it checked out and as predicted it is a little mass of soft tissue (i.e a cist, which is not uncommon on my mom's side) although the generally don't do anything unless it gets too big, in my case it is right on the knuckle and is pretty much constantly sore. So I will be getting some really minor surgery next week to get it removed.

Projects

Electronics wise, I am still waiting on my Thaoe dev board. Last news is that it is expected to ship towards the end of the month. So I will likely have to wait a few more weeks. In the meantime, I have been looking at LCD options and a few other gizmoes for the intercom system. I am also considering another project (which I may run in parallel) which would consist of developing my own cell phone (or smartphone). Seems somewhat odd considering the components are out there. But I can never find a phone which has only the features I want. And I am curious if such a project could be done with over the counter parts at a reasonable cost. I have ordered some of the parts to get started. I will post more on both projects in the next day or two, but right now I am just too tired and need to go to bed :)

Publishing wise, well I am running behind schedule. Pushing out a new edition of Practical .NET 2 and C# 2 to the printer and working on the edits/layout of two other books. I still need to square a few things off with the distributor and once this is done, I will likely send out a press release and make a more official announcement.

Work

Overall, work has been going well. Still hard to find the focus and energy that I once had. Not that I don't want to work on my tasks, just that I sometimes have a real hard time focussing. Hopefuly with the new med change, if this reduces my cycling this should allow me to be a little more focused and consistent.

I still find it somewhat annoying that there is the big cloud of doubt hovering over my head. I can understand that management is worried about my future performance. But I think they lack understanding about what I went through and that it's not because of work. It was just one drop in the bucket that lead to an uncontroled depressive bipolar episode. I have this feeling and expectation that I should be back at 110% or else I am not sufficently productive anymore any should consider moving along. But this added external pressure is definetly not helping when it comes to self-esteem and self-confidence. Some days, it sure doesn't help me find the energy and motivation to make it through the day.

A Little Addition to my Home Automation Project.

sebby1234 — Thu, 12 Apr 2007 17:33:00 GMT

Just found this BLOG POST which includes a video demonstrating the use of the .NET Micro framework with the freescale reference board. Really shows how easy it can make the development of an embeded application!

Staring a New Hobby Project: Home Automation System

sebby1234 — Wed, 11 Apr 2007 22:27:00 GMT

My new house is outfited with an old (I mean 20 years old) intercom system. Although the system itself is still functional, I want to create a new open-source and flexible system to replace the existing system. Since my background is in Computer Egineering (which includes some electrical engineering), I thought it might be a good change of pace for me to move away from a software oly project towards something that is more electronic in nature. In other words, somewhat of a "crafts for geeks" project :)

I have already started to post about the project on SebbyLive but thought it might be a good idea to do a quick recap of what I have so far. Obviously not too much since I am in the early design stages.

Main Goal

The main design goal is to create a replacement for my current home intercom system. Of course, by taking advantage of current technology, I want to integrate features such as:

Touch screen LCD display, allowing a more friendly user interface
Support for streaming audio and video (from security camera or TV feed)
Home automation (control of lighting and other electronics) from the touch panels
Sensor integration such as motion sensors and temperature sensors
And probably much more as I start doing the actual design

With this in mind, I want to keep the design as open as possible so new features can be added in the future without the need for a complete redesign. The first step so far has been to select the right CPU and architecture to work with. Since one of my goals is to have a touchscreen panel in almost every room of the house there are a few key things I had to keep in mind.

Cost: Since there will be a panel unit in almost every room, the cost per unit needs to be as low as possible
Flexibility: Although there may be an initial set of features that will be integrated, the design should allow the addition of new features and sensors with little effort
Ease of Use: The user interface is an important part. Although, I am the geeky type. Non-geeks, such as my wife, need to be able to use the system
Easy of Installation: The idea is to make the installation process as easy as possible. Since we already have an old system in place, we want to use as much of the existing infrastructure as possible (as long as it does not interfere with other design goals)

Spent several days surfing the net and looking at several options. Then I came across one processor/architecture option which answered most of my needs.

Freescale has unveiled a reference design that runs the .NET Micro Framework and targets Windows Vista SideShow, among other applications. The i.MXS Development Kit is based on a highly-integrated SoC (system-on-chip), and supports designs such as external laptop displays that run mini-applications without booting-up a laptop. The core of the kit is a small form-factor reference board based on a Freescale i.MXS applications processor, a "highly integrated" SoC built around an ARM920T processor. The kit also includes a 2.5-inch QVGA color LCD panel, a USB interface, and an expansion connector for add-on modules to support functions such as Bluetooth or ZigBee wireless.

Key features of the development board, according to Freescale, include:

Processor -- i.MXS applications processor, based on ARM920T core
On-board memory:
- 32MB SDRAM
- 8MB "burst flash"
I2C and SSI bus connector for connection to external audio CODEC SMbus interface
On-board 2.5-inch QVGA resolution LCD with backlight
USB 1.1 interface
Serial ports:
- One RS232 port
- One CMOS-level port
11 digital I/O lines for keypad/button inputs
Clock source crystal: 32 kilohertz
LED power indicator
Powered by USB bus voltage or external power adapter
Provides headers for custom add-on modules

That being said, the actual dev kit from freescale is fairly pricey at $600. But two main things stood out. The all in one processor offered by free scale. And the new .NET Micro Framework. Ok, I am biased since I do indeed work for Microsoft. But the idea of being able to develop the home automation code in C# is really attractive to me and would make the process so much easier. After digging a little more I stumbled upon a company named Embeded Fusion which has been developing it's own .NET Micro Framework solution around the freescale architecture...

The "Tahoe" development platform provides an ideal development system for the Meridian CPU and the .NET Micro Framework. The platform includes:

Meridian CPU with .NET Micro Framework
2.7 inch LCD
Push Buttons (9) (5 arranged in classic NSEW with center pattern)
Easy access to all of the pins from the Meridian CPU
Power adapter
DB-9 serial
SDK with customized emulator for .NET Micro Framework
Lot's of sample code! (Including custom emulator extensions and managed drivers)

Their dev kit does appear to offer more options and is more attractively priced at $300. So I have ordered one. :)

They are starting production this month so I should be recieving my board within the next few weeks and can start playing around with it...