Manager: Michael Kuba
Premise: Use an Arduino, pressure sensor and other parts to create a customizable boost guage.
Honeywell Pressure sensor
7805 voltage regulator
JST SM Plug + Receptacle Cable Set x4
Waterproof Polarized 4-Wire Cable Set
i2c / SPI character LCD backpack
Adafruit Perma-Proto Quarter-sized Breadboard PCB
Background information on the Arduino board: http://arduino.cc/en/Main/ArduinoBoardUno
The Honeywell sensor I used has three leads - ground, positive data, and negative data (negative data just flips the voltage). Positive data goes to pin A0 on the Arduino. Recommend consulting the datasheet with your specific sensor - I used SSCDRRN030PDAA5, but significant construction benefits could be found using a sensor with a larger connector. I recommend staying with the SSC series - the NSC series, for example, is uncalibrated and outputs a raw signal, while the SSC series outputs e.g. 0-5 V. Slight changes to the math in the code might be necessary. FYI - The math in the code has been optimized by using integer math.
I used the Perma-Proto quarter-sized breadboard pcb to connect wires to the Honeywell sensor. I cut another one in half and used it for pin breakout on the Arduino board, as well as a place for the 7805 voltage regulator. The voltage regulator was used to drop the 12VDC commonly found in cars to 5VDC for the Arduino and Honeywell sensor. Since the voltage was now regulated, it was connected directly to the 5V pin of the Arduino board.
Theory and assembly of the i2c/SPI character LCD backpack and LCD screen can be found here: https://learn.adafruit.com/i2c-spi-lcd-backpack. The code I used was pretty much copy and pasted from there, using the same wire connections.
The i2c LCD backpack has been optimized by using the LiquidTWI library, shown here: http://www.youtube.com/watch?v=IpwqGJwn1FY (link to library is in video description)
I used the JST SM plugs from Adafruit to connect the arduino and LCD screen circuits for ease of installation into the car. I used the Waterproof Polarized 4-Wire connector for the connection to the actual boost gauge circuit, since it was in the engine bay.
There is an option in the code for personal preference or debugging: on line 14, the code is:
boolean minmax = false; //flag for boost graph or max and min boost
The flag “false” can flipped to “true” to display the minimum (read: vacuum) and maximum boost levels since the gauge was last turned on.
I used an SLA to build the cases for everything - there is a box for the pressure sensor board, a box for the arduino, and a box for the display. The display box is a little small for my display, I had to widen it by about 1 mm all around. I also filled the pressure sensor board box with an electronics potting epoxy to protect the parts from any weather the car might see. STL part files here: https://www.dropbox.com/sh/ew7orezujg0shs8/AADgiSFyteHLHVaF0Uk0SBtVa
More ideas on the build: http://www.seatcupra.net/forums/showthread.php?t=348592
Arch Reactor is proud to host the only St. Louis 2600 meeting. All 2600 meetings are open to the public. Visit stl2600.com for more information regarding topic.
More details about 2600 can be found at http://www.2600.com
Mars Base 2076
Sunday, May 8th
Tuesday, May 10th
*open to public free class*
This will be a in depth look at 3D printing, from taking a sketch all the way to printing out your design. This will include talking about the advantages and disadvantages of different 3D design software, like Google Sketch Up, and Autodesk Fusion 360 to name a few. We will look at many different 3D printers including Delta and Cartesian style. We will also have many printers available to use/see including a UV resin based SLA Form 1+.
Thursday, May 12th
We are participating in the Hackaday Prize contest. We are building an Internet of Things Microscope. We will have weekly meetings through the remaining stages of the competition.