IQU - Introduction & Objectives
The Forget Me Not Design Challenge provides an awesome kit to learn about EnOcean in conjunction with the new Raspberry Pi.
Other sponsors include Tektronix, who is supplying a TBS1000B-EDU oscilloscope to 15 contestants and Element 14 who is supplying a Cadsoft license and a $500 voucher for parts. I don't need to explain to this community just how phenomenal this kit is, but I am certainly very impressed with the generosity of the sponsors and I feel exceptionally fortunate in being selected to participate, especially since the theme of the challenge and the application space for EnOcean fall squarely in one of my favourite technical interest areas - home automation. These little solar cell powered wireless sensors are amazing - they work without wires and without power.
I hope to do justice to the sponsors by utilizing and showcasing everything in the competitor package. This will include at least one PCB designed with Cadsoft Eagle, and electronic signal troubleshooting with the Tektronix oscilloscope because these are such fantastic components of the design kit.
Home automation sounds interesting to many people because of the potential to save energy, reduce costs, increase safety and reduce workloads for owners. However it can be a daunting proposition requiring high initial costs, extensive learning curve, high technical risks and unproven benefits. My objective with this project is not to implement some uber-complex, technically impressive system, but rather pick some specific applications that I find compelling because of their utility. I want to showcase how simple and painless EnOcean has made it to make each function work, hopefully inspiring more of the community to try their hand at whichever application irresistibly appeals to them. I plan to also merge all of the individual applications into a single system to show how easy it can be to add functionality for those users who want to go beyond a single application.
System Description
IQU is a twitter friendly version of "I Cue You" - meaning I am reminding you - of whatever you forgot. The IQU system will actually be an expandable collection of sensors and control modules to provide remote status information about a home and permit remote control of appropriate subsystems. Control is a bit beyond the reminder theme, but there is one control function in the initial plan, mainly to show that EnOcean can be expanded well beyond simple sensors.
Assuming I can obtain all the necessary parts the initial set of features that will be implemented for this challenge include a smart mailbox, a smart doorbell, a smart door lock, a smart window and a smart coffee maker.
Smart Mailbox
The smart mailbox notifies the owner of mailbox activity and reminds them to collect their mail when appropriate. This application is most compelling for folks like my brother who cannot see their mailbox from their house, allowing them to avoid unnecessary trips to check the mailbox, especially in winter. This application will use an EnOcean STM320U, which is powered by a solar cell, to sense the mailbox flag position and transmit it wirelessly to the host controller. Mailbox activity will be monitored, logged and a notification will be sent to the owner.
Smart Doorbell
There are many instances of doorbell "spam" where people come to the door peddling some scam that the dweller has no interest in. It would be nice to know who is approaching or at the door before dropping whatever you are doing to answer the door. On the other hand, it would be really nice to see a delivery person bringing some goodies from element 14 - much more likely to warrant interrupting some pretty engrossing private activities. (depending of course on individual priorities and whether it is an oscilloscope delivery)
The smart doorbell notifies the owner that someone is approaching and shows them video of the person approaching. It also will capture a picture and save it in the log of door activity in case you are not home. The imaging functions will be performed by a Raspberry Pi with PiCam and a small video display. Approach detection will be performed by an EnOcean IR sensor (if I can get one) - mainly to trigger the snapshot image and timestamp. The door activity log will be available online.
I will be making a power supply PCB to run the 12 volt LCD display for the PiCam using Cadsoft Eagle.
Smart Door Lock
Some doors do not automatically lock when closed and when there are multiple occupants sometimes people leave the door unlocked, assuming someone is home but who has actually already left.
The smart door lock is the first step in bringing peace of mind about whether the door is locked or not. It will use an EnOcean solar-powered wireless magnetic switch (STM320U ) to monitor and publish the door lock position code, so it can be accessed from any smart phone or computer.
A future enhancement, which is beyond the reminder theme of the challenge, would be to actually allow the door to be locked remotely.
Smart Window
One of the windows in my house is prone to letting rain in when it is windy. Since the person who opened the window may have left the house, it would be nice to alert other occupants that the window is open when it is raining.
The same sensor device would also work in a vehicle in the driveway, to remind the owner when the windows are down and it is starting to rain.
The smart window will use an EnOcean solar-powered wireless magnetic switch (STM320U ) to monitor and publish the window position of a rain-prone window. A separate (solar) wireless EnOcean switch (STM 332U) will monitor whether it is raining, allowing the owner to know when the window is in jeopardy of allowing rain in.
Smart Coffee Maker
For us, one of the devices most likely to be inadvertently left on when we leave the house is the coffee maker. This is a waste of power and a potential safety risk.
The smart coffee maker notifies the owner of its status via an EnOcean switch (STM 332U) and allows it to be remotely turned off using an EnOcean plug-in switch module. EPSM (OEM)
Remote Access
I do not know much about Eclipse/OpenHAB or EnOcean software yet but I assume they will allow easy implementation of a small web server allowing the owner to view the status of all sensors and control the coffee maker via a web browser from any remote location. If they seem overly complex, I might write my own host software.
Status of the windows and door locks would be shown as codes, so it won't be obvious to uninformed viewers what the status is even if they obtain a password.
Enocean Sensor Packaging
Enocean sensors are nice and small and extremely low power, operating off scavenged power, but they arrived as circuit card assemblies with no enclosures. I finally have a 3D printer (Cel Robox) so I can make proper enclosures. The solar cells need access to ambient light so I am printing the enclosures out of clear PLA. The bases have pockets for the various connectors and components on the underside of the circuit boards and the lids simply snap on. Since the devices do not need wired connections it is possible to completely seal the enclosures against moisture with a little adhesive.
Project Status:
So far I have been:
- collecting and assimilating reams of literature
- trying to bootstrap myself up the learning curve on EnOcean hardware, communications protocols and software
- solidifying the design elements and starting detailed design
- determining what components need to be ordered
- scouring the web for appropriate parts
- ordering long-lead parts
Next Steps:
- use Cadsoft to design a power supply circuit card & order PCB
- complete detailed electronic hardware design
- order remaining electronics parts
- start mechanical design
- set up a software development environment & start exploring software
Links to other blog entries on this project:
http://www.element14.com/community/videos/13262/l/eagle-design-demo
http://www.element14.com/community/videos/13848/l/dolphinviewbasic
http://www.element14.com/community/videos/13858/l/iqu-vb6-demo-1
http://www.element14.com/community/videos/13849/l/iqu-vb6-demo-2
http://www.element14.com/community/videos/14036/l/iqu-smart-window
http://www.element14.com/community/videos/14038/l/iqu-door-approach-video-system
Top Comments
Cool - the sign alone is probably enough to keep people on their best behaviour.
Is it more unethical to put the sign up with no camera or to use the camera with no sign?