ECE497 Project Coffee Pot Control
Embedded Linux Class by Mark A. Yoder
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I'm using the following template to grade. Each slot is 10 points. 0 = Missing, 5=OK, 10=Wow!
08 Executive Summary 04 Installation Instructions - Details are missing 09 User Instructions 10 Highlights - Nice videos 10 Theory of Operation - Nice "Theory of Operation" and Instillation sections. 10 Work Breakdown 09 Future Work 10 Conclusions 08 Demo - Seems a bit hacked together. Didn't see the video capture. 10 Not Late Comments: I'm looking forward to seeing this. Score: 88/100
Our project is to use the BBB to create a web interface for a common home coffee pot. Our web interface should allow (should allow? What does it do?) users to schedule brew times, see a photo of the current coffee pot, see the temperature of the liquid; additionally the BBB should turn off the coffee pot when it is running dangerously low to avoid sludge at the bottom of the pot and notify the user via email when the pot should be refilled .
Currently, our project accomplishes the goal of allowing users to schedule brew times, see a photo of the coffee pot, and plot the temperature all from a web interface.
Currently, our project does not accomplish the goal of notifying the user when the pot is running low and turning off the pot. We cannot accomplish this because the Sparkfun pressure sensor that we used to determine how much liquid is in the pot cannot withstand the heat of the burner.
In fine (fine?) , this project demonstrates the ease at which a maker can automate their environment. The BBB's ability to simplify GPIO and I2C interfaces along with node js's extensive repository modules makes interacting with the outside world simple
We have not put any work into final packaging. This project simply represents the rapid prototyping capacity of the BBB.
The Hardware used in this design includes the following
Place the pressure resistor under the coffee pot. It is important to maintain consistency in the placement of the coffee pot relative to the resistor as well as the resistor relative to the burner. Currently, this piece of hardware is a weakness in the design. It cannot withstand the heat of the burner. If a replacement piece of hardware can be found this wiki will be updated. Additionally, it is necessary to calibrate the code to fit with your particular coffee pot.
The Temp Sensor that we used is from Dallas one wire. It communicates over serial one wire communication. It simply needs to be somewhere in the middle of the liquid.
- Playstation EyeToy (Looks like a different camera)
The PS Eyetoy is hooked into the USB input on the BBB.
The PowerSwitch Tail II is essentially a relay that can be used to switch a load that is connected to a wall outlet using a small signal from one of the BBB's GPIOs. Connect the GND and IN- to GND and attach IN+ to P9_13 for the current code configuration.
How do I wire the hardware?
The first time:
1.set environment variable
add the following lines to the end of the file:
exit beaglebone and login again export The result should include SLOTS and DTS.
2.install something (install.sh and setup.sh files are missing.)
npm install ds18b20
npm install http
npm install fs
npm install child_process
npm install crontab
npm install nodemailer
npm install socket.io
git clone https://github.com/twam/v4l2grab.git
make (This doesn't work for me.)
3.1 for the camera to work
connect the camera to the beaglebone with USB
check /dev/vedio0 is showed
test camera using the command
v4l2grab -W 160 -H 120 -o test.JPEG
3.2 for temperature sensor to work
check the hardware connection
make sure HDMI is disabled and eMMC is enabled
uncomment all things related to P9_12
cp ./src/arm/univ-emmc-00A0.dtbo /lib/firmware
echo BB-W1-P9.12 > $SLOTS
to check BB-W1-P9.12 is loaded. (How do I know it's loaded?)
28-000008291724 is the id of the temperature sensor. Every temperature sensor has a its own id. So be sure to check that and go to that directory.
then the temperature will be showed.
3.3 for scheduling time to turn on coffee pot to work
on host computer(run specific shell):
on beaglebone(check the time is OK):
to check if gpio31 appears(GPIO31 pin is used to connect the coffee pot)
echo gpio31 > export
./boneServer.js (I get an error.)
Go to the browser and go to 192.168.7.2:9090
You only need to start from step5 and step6.
The following graphic should assist a new user in navigating our webpage.
Theory of Operation
List the major tasks in your project and who did what.
Also list here what doesn't work yet and when you think it will be finished and who is finishing it.
- Setup web interface Hang Du
- Set Brew Alarm Hang du
- Send Email upon empty pot condition James DiTucci
- Turn Off Pot upon empty pot condition James DiTucci
- Take Picture of Pot Hang Du
- Take Temp Data Hang Du
Future work on the BBB Coffee Pot would include, choosing a suitable pressure sensor that can withstand the heat of the coffee pot. Unfortunately, the pressure sensitive resistor that was available to us cannot stand up to the heat of the coffee pot burner. The pressure sensor enables two neat features which are already implemented in the code: first the Bone will shut off the coffee pot when it senses the pot is critically low as to avoid evaporating all the liquid leaving gross coffee sludge in the bottom of the pot, second when the Bone senses the pot is running low it will notify the user of the event over email. currently, neither of those functions are actually implemented because we don't have the proper hardware. Future work on the software side would be to make the web page more user-friendly and aesthetically pleasing, create a system for user accounts, and increase the security of the BBBCoffeePot@Gmail.com email address. Currently, the password is plain text in the boneserver.js file.
At the end of this project, the biggest takeaway for me is how painless it is to develop a very useful device. Most of the struggle was finding the appropriate hardware. Using Node JS modules makes fairly complex tasks such as reading an analog input and sending simple. An area we should improve on is our web dev skills. The website is easy to use but looks sloppy.
One really interesting idea I had towards the end of the project that could take this in a completely different direction is using PWM the relay and the temperature sensor that we have to control the temperature of the liquid using a PID control scheme.
Embedded Linux Class by Mark A. Yoder