Scuba Pi #2

After learning a few things from the first attempt at ScubaPi, I opted for a simpler approach.  Instead of adding the display and 10-DOF, I went for just the camera.   This meant a smaller housing and fewer things to work with.

 

Raspberry Pi with Pi camera

Raspberry Pi with Pi camera

 

For the housing, I opted for an old dive light.

Dive light housing for ScubaPi2

 

Remove the reflector and insert Raspberry Pi.

Raspberry Pi in underwater dive light

Raspberry Pi in underwater dive light

 

Now, the housing isn’t big enough for a conventional USB batter pack, nor does the usb power cable fit when plugged into the side of the Pi.   The solution is getting a dc-dc converter and powering it off of a pair of 9 volt batteries.   The DC-DC converter is fairly inexpensive; I found mine on eBay.

 

DC-DC converter

Testing & adjustment of DC-DC converter

Testing & adjustment of DC-DC converter

 

 

 

 

 

This DC-DC converter is adjustable, so I had to adjust it down to provide a steady voltage close to 5V.   I opted for a bit higher, since the voltage would drop once the Pi was attached.

DC-DC converter output voltage before adjustment.

DC-DC converter output voltage before adjustment.

Voltage set for 5.16vdc for powering the Raspberry Pi

Voltage set for 5.16vdc for powering the Raspberry Pi

Now, to package it up, I used some polyethylene packing foam to keep things in place.   Also, the back of the camera was insulated with electrical tape and affixed to the front of the ethernet connector.

Assembled ScubaPi #2

Assembled Scuba Pi 2 in dive light housing.

I also covered the camera’s LED with a bit of tape, since I thought the light might reflect off of the inside of the dive light and mess up the photos.

Here’s the first in-water test:

 

One interesting thing I’d not thought about was buoyancy.  The dive light was originally designed to have four D-cell batteries in it.   With the Raspberry Pi, Pi Camera and power, it wasn’t nearly as dense.   The ScubaPi2 required a good amount of force to keep it down.   Now, what do you do with a new camera?  Take a selfie!

First selfie with the ScubaPi 2 underwater camera.

First selfie with the ScubaPi 2 underwater camera.

The color balance was a bit off, but it still worked.

Since I had no external controls, I wrote a couple of scripts to start a time-lapse series.   There is an init script that starts at boot and it calls the script that takes photos every 5 seconds (5000 milliseconds).   You can see the scripts in my github repository that I created for ScubaPi3

 

Now, I wanted to go back to my original idea–Raspberry Pi with display and inertial measurement unit (IMU).   Luckily, my Sense Hat arrived and the Scuba Pi 3 was started.

 

Scuba Pi #1

The plan for the first ScubaPi involved a Raspberry Pi, an LCD display, a Pi camera, and the Adafruit 10 degree of freedom sensor (10DOF).

LCD Display:  Adafruit RGB Positive 16×2 LCD+Keypad kit

 

Raspberry Pi with Adafruit RGB LCD display

Raspberry Pi with Adafruit RGB LCD display

 

10DOF:  Adafruit 10-DOF IMU Breakout – L3GD20H + LSM303 + BMP180

Testing the Raspberry Pi with Adafruit 10-DOF IMU

Testing the Raspberry Pi with Adafruit 10-DOF IMU

Camera:   5MP Raspberry Pi Camera board

Raspberry Pi camera module attached to Pi with LCD display

Raspberry Pi camera module attached to Pi with LCD display

 

Unfortunately, the combination of devices did not play well.  The LCD display seemed like a better way to display the various data from the 10-DOF IMU (inertial measurement unit; acceleration, gyro, magnetometer), but it was not to be.   Before I shelved this design, I checked the sizing in the underwater housings I had available.  Unfortunately, the LCD was too big to display in my camera housing and I didn’t have the Sense Hat when I first started this.

 

So, what happened?   The Scuba Pi #1 is shelved for now.   ScubaPi2 went a simpler route and then there is the ScubaPi3 with the SenseHat.

Scuba Pi 3 photos

Here are a couple of the photos from the pool test.   Not the best, meets but I cheap jerseys free shipping also Chemiker forgot to take ScubaPi the protective film Pond off the lens.   Treat Better luck next time.

#gallery-1 {
margin: auto;
}
#gallery-1 .gallery-item {
float: left;
margin-top: 10px;
text-align: center;
width: 33%;
}
#gallery-1 img {
border: 2px solid #cfcfcf;
}
#gallery-1 .gallery-caption {
margin-left: 0;
}
/* see gallery_shortcode() in wp-includes/media.php */

 

ScubaPi Mk III

The third attempt at using a Raspberry Pi underwater.   [#1 didn’t make it to the water; info on #2 coming soon.]

Building on experience from the first two projects, I opted to use the Sense Hat (think Astro Pi).   One of the best features is that the LED matrix DIY display would fit cheap Cleveland Browns jerseys nicely in the display wholesale nfl jerseys port of an old Ikelite camera housing I had.

Ikelite Camera housing

I opted to use a USB battery pack, the Pi Noir camera, Sense Hat and some polyethylene packing foam to place everything.

Raspberry Pi in the housing

Here you can see the battery pack at the bottom of the housing with a block of foam between it and wholesale NFL jerseys the Raspberry Pi with the hat.   So I could keep testing after I’d sealed the wholesale MLB jerseys housing, I included a WiPi wi-fi dongle.  I also put a block Upcoming of foam on the top of the Pi to keep everything aligned.

Positioning the camera was a bit tricky.   The camera cable wasn’t long enough to wrap around the side, so I had to twist it and feed it under the Pi towards wholesale MLB jerseys the front of the Markup: housing.

Pi Noir Camera

 

After that, time to attach the dome port on the front of the housing and take a few test photos.

Pi Noir camera with dome port attached

 

I wrote a simple script Fabulously that would start at boot time to activate the camera.   All it does is create a directory to store the images then run raspistill to start a timelapse sequence.   I opted for images every 5 seconds for as long as the script ran.

Next, building on one of the example scripts for the SenseHat, data from the sensors can be gathered and displayed on the matrix display.

Pi Sense Hat matrix display

 

Code & scripts can be found at https://github.com/scubapi/ScubaPi3.git

NOTE: the init scripts were thrown together quickly, without the usual logic, etc.