Difference between revisions of "Turtle Sense/Phase Two"

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Phase two is starting up.
 
 
 
==People==
 
==People==
*[[User:Dave]] -- Electrical engineering
+
*[[User:Dave]] -- Electrical engineering / Mechanical engineering
*[[User:Sam]] -- Project manager / Software
+
*[[User:Sam]] -- Project manager / Embedded Software
 
*[[User:Tom]] -- Engineering support
 
*[[User:Tom]] -- Engineering support
 
*[[User:Eric]] -- Fundraising / Community liaison
 
*[[User:Eric]] -- Fundraising / Community liaison
*[[User:Chuck]] -- Documentation/fundraising
+
*[[User:Chuck]] -- Sea Turtle community outreach / Materials
*VOLUNTEER NEEDED -- Web Design and data display
+
*[[User:Chris]] -- Web Server Admin
 +
*[[User:Mark]] -- Web Application Development
 +
*[[User:Britta]] -- National Park Service Biologist
 +
*[[User:Trebor|User:trebor]] -- Web visualizations
 +
 
  
 
==Overview==
 
==Overview==
The plan for Phase Two is to create about 30 boards for installation in the Outer Banks of North Carolina during the Spring and Summer of 2013The design is based around creating a sandwich of off the shelf boards (one for low power computing and the other for telemetry). Both of these boards will be plugged into headers on a custom mother board we will designEvery thing on the mother board will have through-hole components to make the board as easy as possible to assemble.  The idea is to have a set of instructions on this web-site which will allow anyone who can do basic soldering to order the parts (from the manufacturers) and quickly assemble a board, install it on a nest (with approval of the appropriate agencies) to communicate with a website we will construct to monitor and collect the data from the nests.
+
When nests are discovered by park personnel, they are uncovered, the eggs counted, and a DNA sample is takenAt that time, a smart sensor the size of a turtle egg is placed on top of the turtle nest before the excavated sand is filled back in to cover the siteThe smart sensor measures motion and temperature in the nest, and the data collected is used to predict when hatching is imminent.  The smart sensor is connected to a communications tower which sends out regular reports on the activity in the nest using M2M technology.  The text file reports are FTP'd to a website directly from the communications tower. During Phase Two we created test units, one registration units, 8 communications towers and 24 smart sensors for installation in the Outer Banks of North Carolina startin in the Spring of 2014. Many of the sensors can be used in more than one nest per season, so Data can be collected from roughly 40 nests per season. The data is analyzed as it is collected to attempt to predict imminent hatching.
  
==Organization==
+
===Commercial options===
'''Conference Call Sea Turtle Project Oct 18, 2013  2:15 pm Pacific time.'''
+
Before developing the system, other commercially available data recording systems were evaluated to see if anything that would meet our requirements was available.  None of the options we found were not low enough power to fit our needs, and none provided the data we were hoping to collect. The closest matches we found would have required as much or almost as much custom engineering on our part to make it work, and there was no cost benefit to going that route.
Free Conference Call 213 493-0700, then 346192#
+
*[[Chuck's research on data recorders]]
  
Participants: Tom Zimmerman (tzim@us.ibm.com),  Sam Waltman (sam@waltman.net), Dave Hermeyer (dave@hermeyer.us); Eric Kaplan (ekaplan@hiocenter.org). Charles Wade (cwade@yahoo.com)
+
==Hardware components==
 +
===Smart Sensor===
 +
The Phase One design used plastic ping-pong balls (not good ping-pong balls, but cheap plastic knock offs) and a temperature/motion sensor pre-installed on a small circuit board ([https://www.sparkfun.com/products/11446 Qty 1 Price=$14.95]).  Assembly involved cutting a small slot in a ball, putting in some silicone caulk, inserting a sensor board attached to a cable into the caulk, and then filling the rest of the ball with caulk.  A  ball cut in half covered the slot and makes a thorough seal with the silicone.  This design was abandoned for several reasons. The silicone did not fully set, even after a few months in the field. The sensor was unreliable, which may have been because it was connected directly to the microprocessor via the long Cat 5 cable and communications were using a very slow bit-banged SPI connection.  To improve communications we decided to put transceivers on both sides of the cableBy adding a microprocessor to the sensor, most of the processing could happen in the sensor assembly. The tranceivers are on for just a few seconds a day, for the upload of information from the sensor to the comm tower. This results in a Smart Sensor with very small power requirements.
  
AGENDA
+
The Smart Sensor has a 3-axis motion sensor (accelerometer) and temperature sensor connected to a very low power TI MSP430FR series microprocessor.  There is also an RS485 transceiver chip which connects to the communications tower via a shielded Cat5 cable.  The smart sensor can be programmed to take readings 12.5, 25, 50, 100, 200 or 400 times every second.  Each reading is compared with the previous reading to determine the change in acceleration -- or "jolt".  Rather than record each jolt, the sensor counts how many readings have reached approximately 25 different magnitude levels.  These magnitude levels (which we call "bins counters") are in a logarithmic scale.  Each bin is the square root of 2 larger than the previous one.  We keep count for a variable amount of time (between 1 and 6 minutes) and then start a new set record with a new set of bins.  This allows us to track how much motion there was at multiple magnitudes over time.
  
      Intro: Zimmerman, brief introduction of Wade (present for first time)Wade had sent email items prior to phone conference (attached).
+
===Communications tower board===
 +
Since it is not possible to make telemetry connections under wet salty sand, the smart sensors are connected to a communications tower.  The design is based around creating a custom processing mother board connected to an off-the-shelf telemetry board. The communications board has a very low power  TI MSP430FR series microprocessor which controls and monitors the activity of the smart sensor and controls the telemetry board. There is also a power supply, a RS485 telemetry chip and connectors for future expansion.  The electronics are mounted inside a 3 inch PVC pipe and fittings anchored in a bucket filled with concrete.  The concrete base and Cat 5 cable are buried in the sand. The  The tower sends text reports to our web space via an FTP connection using the telemetry board.  The frequency of the reports starts out a one a day when the nests are new and not very active.  Later the frequency increases to 6 times a day as the nest becomes more activeSince the communications tower only makes one to 6 reports a day, The microprocessor turns the telemetry board on and off, so that it consumes no power when it is not being used.
  
1. Finances. 
+
====Telemetry board====
It appears we need at least $15k for 30 units.  Eric: NPS will do $50k/year for awhile. They now derive revenue from charges to drive on beach which may be the fund source.  Available 2014 (Eric to follow up)?  If so, this may cover our expenses next year?
+
We are using [http://www.janus-rc.com/terminuscf.html plug in Terminus boards] made by Janus. One board works with AT&T, T-mobile and many international GSM networksAnother works with VerizonThe boards are interchangeable so both will plug into our motherboardThe cost is roughly $140 qty 1 and are [http://www.janus-rc.com/terminuscf.html available from the manufacturer, Janus]Janus has generously offered us a discount on their boards.  
 
 
2. Other Cities/Areas?
 
Alabama-NASA engineer.  Backend project  perhaps for BBAFF proposal (Kaplan) for NC Coastal Recreational Fishing License Fund. Put eggs in cages?
 
 
 
Bald Head Island, NC. Large organization with strong funding
 
 
 
Audubon Voyager?
 
 
 
3. Web support
 
Sam:  SF person develop9ng mapping for satellite data, sent over internet, which might be useful.
 
 
 
Sam developing Nerd without Borders WIKI.  Strong arguments for open source site which covers what we’ve developed/learned.  Should cover such as teaching (best practices), devices, design experiences.
 
 
 
Long discussion on whether in addition to the public section there should be a private section (just this group). Private may be needed  for legal interactions with future partners.  Issue not resolved.
 
 
 
4. Engineering team, version 2
 
Sam and TomDiscussion as to changes coming.  Comments on need for a time line.
 
 
 
5. Radio version
 
Sam has found volunteers who will possibly create this and perhaps assemble as wellLooking for inexpensive design
 
 
 
 
 
6. Funding
 
Crowd funding (Wade suggestion attached).  Sam has done two of these, noted they are a lot of work and require well-advertised buildup to an event with subsequent follow thruWould require swag and effective donor stroking/communication.  May be beyond our resources. Correct timing and correct dollar goals are critical if we proceed.
 
 
 
Eric: In NC Coastal Fishing grant proposal (Would be summer 2015 money).  $100k in budget. Grant station, Center for Non-profit Excellence (Charlottesville, VA high schoolers working on proposals)? 
 
 
 
DECA marketing programs?
 
 
 
Paradox: environmentalists and the “drive on beach” interests have a common goal in reducing the time needed for path to beach.
 
 
 
7. Other Groups with related goals
 
Seaturtlehospital.org  (Karen Beasley center, topsail island)
 
Lew Browning (associated with Beasley?
 
SeaTurtleConservancy.org
 
 
 
Many web sites.
 
 
 
8. Possible Swag
 
List from Sam and Tom: Pool on  hatching date;  pool on tagged female turtles (GPS) return date for nesting. More??
 
 
 
 
 
9. Division of labor
 
Eric: involvement of Hatteras Island Ocean Center  non-profit; interface with NPS including actions at nest sites; interface with turtle groups., esp North Carolina
 
 
 
Dave/Sam: Engineering/electronic communications
 
 
 
Tom:  Probe device design/construction
 
 
 
Chuck:  admin, funding, searches for effective turtle web sites
 
 
 
10.  Tom IBM availability.
 
Percentage of time he can devote to this is set by IBM management policy.
 
  
 +
===Hand-held registration unit===
 +
A communications board is mounted in a small hand-held unit so that it can be taken in the field when nests are first discovered.  This allows park service personnel to carry just the light-weight sensors and the hand-held unit to the nest sites.  Later, the much heavier and bulkier communications towers can be brought in.  The Hand-Held units have GPS capability.  They are programmed to test the sensors to make sure they are functioning properly, get a GPS reading, check for good cell reception, and get the local time and date from the cellular network.  The date, time and GPS location are sent to the sensor, so that all this information will be available to the communications tower when it eventually connected.
  
 +
===Other components===
 +
The only other components necessary are the cable and connector for the turtle egg sensor, one antenna for the communications tower (the hand held unit has an extra antenna for GPS.)  The units should operate for roughly 4 months running on 4 or 8 low self-discharge NiMH Batteries.    Also, anyone creating these devices will need the hardware necessary for programming the microprocessors.
  
Information distributed prior to conference call:
+
==Cellular service==
 +
We arranged for cellular service through m2mAIR which is part of TELIT, the manufacture of the cellular modules used in the Janus plug-in boards.  This service is cost effective for hosting a large number of devices, as they can all be in the same account with one monthly fee.  The devices are also charged for the data used by each device, but the quota is pooled (shared) between all the devices, and the data rate charges can be modified month by month.  During periods of little or no activity, the data plans can be throttled back to keep the fees to a minimum.
  
Sea Turtles 10-16-2013
+
==Web design and Database==
Some topics for discussion on conference call 10-18-2013
+
All reports are uploaded to our web-space. The reports are comma separated text files with headings and labels, so they can be read by people as well as computers.  We are beginning work on a database to store all the data.  When reports are uploaded, the communications units also check the webspace for a new parameter file and download it if it is found.  The parameter file has settings that effect the behavior of the devices.  Here are some of the things that can be changed:
  
Tom, Eric, Sam
+
*The frequency of reporting during inactive days
 +
*The frequency of reporting during active days
 +
*The number of inactive days
 +
*The number of records per report
 +
*How frequently samples are read by the sensor (12.5, 25, 50,100, 200 or 400 times per second)
 +
*All of the other settings possible for the sensor
 +
*Whether reports are verbose (labels on all the fields) or just data
 +
*Whether temperatures are calibrated
  
Hi.  I’ve been doing work mostly in background and wanted to ship this before our conference call.  I’ve been working mostly on possible funding and volunteer resources while trying to educate myself on the projectsI had a nice discussion with Tom today so I’ve learned a bit more about the interactions in the group.
+
Work has started on designing a database to collect all the data in the reports, and a website to give people access to the dataThis work is just in its preliminary stages in anticipation of Phase 3.
 +
* [[Turtle Sense/Website design]]
 +
* [[Turtle Sense/Database design]]
  
Some topics for information or possibly discussionNote that I have not acted on any of these.
+
==Embedded code==
 +
There are essentially three devices that need embedded codeThe smart sensor, the communications tower units, and the hand-held registration units. All three of these devices use the same microprocessor, and two of them use the same circuit board.  A good deal of the embedded code is shared in the three applications..
  
Possible funding- -especially for support for Summer 2013 devices
+
All the code was written in C using TI's Code Composer Studio which is free for developers of code that is smaller than 16K.
I can do the work  on these but will need some technical backup info on the projects and on turtle behavior plus general ideas of where you wish to focus and what the budget amounts would be.
 
  
1.  I found an appealing website, www.crowdrise.org, which we might use.  It was described in a Forbes article (Top 10 Crowdfunding ..” ) as a “do gooders site”.  They have a very engaging style, which among other things says
+
The code is fully documented and can be seen on GITHUB:
“CrowdRise is a crowdfunding platform for good. CrowdRise is about raising money for amazing causes and having the most fun in the world while doing it. CrowdRise is the official fundraising partner of the New York Marathon, Chicago Marathon and thousands of other events. The world's finest charities, such as Stand Up to Cancer, Robin Hood, American Red Cross, and the Clinton Global Initiative all choose CrowdRise for online fundraising. CrowdRise was named a Top 25 Global Philanthropist by Barron's, the most innovative fundraising platform by Mashable, and was nominated for a Webby for Best Philanthropic Website. Besides that, CrowdRise isn't that great. 
+
*[https://github.com/NerdsWithoutBorders/Turtle-Sense-Smart-Sensor Smart Sensor embedded code]
 
+
*[https://github.com/NerdsWithoutBorders/TurtleSense-Comm-Head Communications tower embedded code]
They have  the Nature Conservancy and Sierra Club foundation as active sites plus hundreds of other organizations (small and large). Charges seem to be a flat 3% of the transactions plus a 2.9% credit card processing fee.  May be different if we go in as a charity (Eric’s?).  Money can go to local charities (Eric’s ?). with easy access They walk you thru the enrollment and website process it seems but it would help to have artistic website expertise involved.  Writeups are short. Their terms and conditions  package is  about 10 pages long from, as they put it, “our mean lawyer”-- which I haven’t digested
+
*[https://github.com/NerdsWithoutBorders/TurtleSense-HandHeld-communicator Registration unit embedded code]
 
 
I’ve never worked with one of these, but obviously the goal is to somehow have enough publicity so people know about it .  (bit more below under Other Resources).  It is good to have a feedback of some type (small plastic turtles? T shirts?)  Donor names can be listed plus they have a system of award heroes depending on how much is raised.  Tom and I briefly discussed perhaps using SeaTurtle.org to positive effect for donors?
 
 
 
2.  IBM On Demand Community.  Internal  corporate site, funds open about March, up to 2 K or so with minimal bureaucracy and quick decisions.  An hour or less to do the proposal.  Funds go to a charity (at least the many I’ve done).  Rules change a bit year to year but bigger funds possible if lots of IBMers involved (will be easy to get, probably). 
 
 
 
3.  IBM IVOC grant—within Almaden, perhaps $1200, may be able to get a bit this year.  They balance demands/vs. money in the pot.
 
 
 
Other Resources—haphazard order
 
 
 
In casual conversations, I’ve found the interest in this project to be very high.
 
 
 
a. Publicity: we can get some informal help and suggestions from IBM communications  but they have to be very careful about corporate commitments in the government/political arena.  We have two such experts in Almaden and one of my friends lauded the wife of one of them (she’s not an IBMer) who helped his high school robotics program get PR and perhaps some funding.  Mike Ross, a scientist and former IBM communications person, now an independent writer, would help also I’m certain.
 
b. UC Santa Cruz has a class/department on Wildlife Illustration.  They also have a well known technical writing master’s program.  Perhaps we can seed something there.?
 
c. MIT has a January undergrad research period for undergrads that has an internal funding source…and they are pushing that program.  No doubt other schools have something similar.  Perhaps get seed funding there?
 
d. In casual conversations (part of the basis for my comment on the interest)
 
      -one of my friends volunteered that his son has an advertising company and might be interested in doing pro-bono web and advertising
 
      -one of the Almaden postdocs at lunch got very excited—he’s interested in turtles of all types,  wants to send me lists of organizations, would like the project to extend to other turtles besides those in NC.
 
      -a local author of children’s books  knows good illustrators who might be interested
 
      -my son is starting an online business and has sampled website designers in  San Luis Obispo, CA—college town, and no doubt some of these would love to have their name on a worthwhile project.  Ditto Silicon Valley?
 
     
 
Organization
 
In my discussion with Tom today I suggested he shift to me his admin work, from scheduling conference calls to whatever else. I can give it priority, and he should have as much time as possible on version 2 or 3 or whatever—just a thought.  Maybe there are other ways I could help.
 
 
 
Cheers, chuck
 
     
 
     
 
     
 
     
 
     
 
     
 
 
 
 
 
 
 
 
 
 
 
== Engineering ==
 
===Components===
 
====Turtle egg sensor====
 
This would be unchanged from the phase one design that uses plastic ping-pong balls (not good ping-pong balls, but cheap plastic knock offs) and a temperature/motion sensor pre-installed on a small circuit board ([https://www.sparkfun.com/products/11446 Qty 1 Price=$14.95]).  Assembly involves cutting a small slot in a ball, putting in some silicone caulk, inserting a sensor board attached to a cable into the caulk, and then filling the rest of the ball with caulk.  A  ball cut in half covers the slot and makes a thorough seal with the silicone.
 
 
 
====Mother board====
 
The mother board will be custom made and have two rows of headers for attaching a pre-fabricated processing board based on the [http://www.ti.com/lsds/ti/microcontroller/16-bit_msp430/overview.page TI MSP430 CPU] and another two rows of headers for prefabricated telemetry boards.  Each of these boards already have their own power regulators built in, but there needs to be an additional power regulator for the telemetry board on the mother board to regulate battery power down to the voltage required by the telemetry board.  The regulator, headers, and other components on the mother board will all be through hole components that can be easily soldered to the mother board making it easy to assemble for anyone with basic electronic soldering experience (think hacker space events and high schoolers).  The mother board will be approximately 2.5 inches by 1.9 inches.  We can purchase 3 boards for $51 plus shipping.  We might be able to cut each board in half (full size is 2.5 inches by 3.8 inches).  This can be done with a hack saw.  For larger production runs, we can get the boards pre-cut to the optimum dimensions and the price would be a little less per unit (about $7 each for a run of 30).  Other components on the board should total under $15.  Total cost per board $20 to $25 each.
 
 
 
====Processing board====
 
We've found a pre-assembled processing board made by Oilmex Ltd, that is based on the the ultra-low-power [http://www.ti.com/lsds/ti/microcontroller/16-bit_msp430/overview.page MSP430FR5739 processor by Texas Instruments]. The [https://www.olimex.com/Products/MSP430/Header/MSP430-HFR5739/ MSP430-HFR5739 board] has all the essential components needed. There is a header on the board for easy programming, and a connector which we can use for plugging in the cable to the turtle egg sensor. The MSP430FR5739 CPU has 16K Bytes program FRAM, 1024 Bytes SRAM, 10-bit A/D converter, 16-channel comparator with voltage reference generation and hysteresis capabilities which we can use for monitoring the battery voltage, three enhanced serial channels (capable of I2C, SPI, or UART protocols),  hardware multiplier, real-time clock, five 16-bit timers, and more. The board also has power supply filtering capacitor and a 3.3V voltage regulator.  There are two rows of headers for each pin of the microprocessor which we will use to plug this board into the mother board.  The dimension of the board is 2.15" × 1.10".  The boards cost only $19.53 qty 1 and are [http://microcontrollershop.com/product_info.php?products_id=5413 available from microcontrollershop.com].
 
 
 
====Telemetry board====
 
We plan on using [http://www.janus-rc.com/terminuscf.html plug in Terminus boards] made by Janus.  The Janus GSM865CF v1.1 GSM/GPRS Modem with GPS works with AT&T and T-mobile.  For Verizon we can use the CDMA864CF v3.0.  The boards are interchangeable and will plug into our motherboard.  The cost is roughly $140 qty 1 and are [http://www.janus-rc.com/terminuscf.htmlavailable from the manufacturer, Janus].
 
  
====Other components====
+
==Parts lists==
The only other components necessary are the cable and connector for the turtle egg sensor (a couple of bucks at most), an antenna for the telemetry board (GSM and GPS), which costs about $20 (perhaps more if reception is a problem). The units should operate for roughly 4 months running on 4 or 8 low self-discharge NiMH Batteries. The batteries and holder (TBD) which should cost less than $25. Also, anyone creating these devices will need the hardware necessary for programming the microprocessor (more about this later).
+
* [https://dl.dropboxusercontent.com/u/26861868/Turtle%20Sense%20Public%20Files/Turtle%20Sense%20Communicator%20PCB%20v.0.25%20--%20Bill%20of%20Materials.xls Turtle Sense Communications board parts]
 +
* [https://dl.dropboxusercontent.com/u/26861868/Turtle%20Sense%20Public%20Files/Turtle%20Sense%20Smart%20Sensor%20PCB%20v.0.23a%20--%20Bill%20of%20Materials.xls Turtle Sense Smart Sensor board parts]
 +
* [[Turtle Sense Other parts]]
  
The cost of the total project should be around $200 to $250 per unit after start up expenses, and not counting telephony charges.
+
==Schematics and System design==
 +
* [[Block Diagram of System]]
 +
* [[Turtle Sense Smart Sensor PCB Schematic v.0.24|Smart Sensor PCB 0.24 schematic]]
 +
* [[Turtle Sense Smart Sensor board v.0.24|Smart Sensor PCB 0.24 description]]
 +
* [[Turtle Sense Communications PCB Schematic v.0.25a|Communications PCB 0.25a schematic]]
 +
* [[Turtle Sense communications board v.0.25a|Communications PCB 0.25a description]]
  
====Parts list====
+
==Circuit Board Fabrication==
===Schematic and Board design===
+
* [[Turtle Sense -- Manufacturing the Communicator and Smart Sensor printed circuit boards|Manufacturing the Communicator and Smart Sensor printed circuit boards]]
===Microprocessor Programming===
 
===Board Assembly===
 
  
==Web development==
+
==Assembly Instructions==
 +
* [[Turtle Sense cable assembly instructions|Cable assembly instructions]]
 +
* [[Turtle Sense casting instructions for Smart Sensor and connectors|Casting instructions for Smart Sensor and connectors]]
 +
* [[Turtle Sense communicator PVC housing assembly instructions|Communicator PVC housing assembly instructions]]
 +
* [[Turtle Sense communicator housing final assembly|Communicator housing final assembly]]
 +
==User Guide ==
 +
* [[Turtle Sense nest site installation instructions|Nest site installation instructions]]
 +
* [[Turtle Sense nest monitoring instructions|Nest site monitoring instructions]]
 +
* [[Turtle Sense equipment maintenance instructions|Equipment maintenance instructions]]

Revision as of 15:40, 6 July 2015

People


Overview

When nests are discovered by park personnel, they are uncovered, the eggs counted, and a DNA sample is taken. At that time, a smart sensor the size of a turtle egg is placed on top of the turtle nest before the excavated sand is filled back in to cover the site. The smart sensor measures motion and temperature in the nest, and the data collected is used to predict when hatching is imminent. The smart sensor is connected to a communications tower which sends out regular reports on the activity in the nest using M2M technology. The text file reports are FTP'd to a website directly from the communications tower. During Phase Two we created test units, one registration units, 8 communications towers and 24 smart sensors for installation in the Outer Banks of North Carolina startin in the Spring of 2014. Many of the sensors can be used in more than one nest per season, so Data can be collected from roughly 40 nests per season. The data is analyzed as it is collected to attempt to predict imminent hatching.

Commercial options

Before developing the system, other commercially available data recording systems were evaluated to see if anything that would meet our requirements was available. None of the options we found were not low enough power to fit our needs, and none provided the data we were hoping to collect. The closest matches we found would have required as much or almost as much custom engineering on our part to make it work, and there was no cost benefit to going that route.

Hardware components

Smart Sensor

The Phase One design used plastic ping-pong balls (not good ping-pong balls, but cheap plastic knock offs) and a temperature/motion sensor pre-installed on a small circuit board (Qty 1 Price=$14.95). Assembly involved cutting a small slot in a ball, putting in some silicone caulk, inserting a sensor board attached to a cable into the caulk, and then filling the rest of the ball with caulk. A ball cut in half covered the slot and makes a thorough seal with the silicone. This design was abandoned for several reasons. The silicone did not fully set, even after a few months in the field. The sensor was unreliable, which may have been because it was connected directly to the microprocessor via the long Cat 5 cable and communications were using a very slow bit-banged SPI connection. To improve communications we decided to put transceivers on both sides of the cable. By adding a microprocessor to the sensor, most of the processing could happen in the sensor assembly. The tranceivers are on for just a few seconds a day, for the upload of information from the sensor to the comm tower. This results in a Smart Sensor with very small power requirements.

The Smart Sensor has a 3-axis motion sensor (accelerometer) and temperature sensor connected to a very low power TI MSP430FR series microprocessor. There is also an RS485 transceiver chip which connects to the communications tower via a shielded Cat5 cable. The smart sensor can be programmed to take readings 12.5, 25, 50, 100, 200 or 400 times every second. Each reading is compared with the previous reading to determine the change in acceleration -- or "jolt". Rather than record each jolt, the sensor counts how many readings have reached approximately 25 different magnitude levels. These magnitude levels (which we call "bins counters") are in a logarithmic scale. Each bin is the square root of 2 larger than the previous one. We keep count for a variable amount of time (between 1 and 6 minutes) and then start a new set record with a new set of bins. This allows us to track how much motion there was at multiple magnitudes over time.

Communications tower board

Since it is not possible to make telemetry connections under wet salty sand, the smart sensors are connected to a communications tower. The design is based around creating a custom processing mother board connected to an off-the-shelf telemetry board. The communications board has a very low power TI MSP430FR series microprocessor which controls and monitors the activity of the smart sensor and controls the telemetry board. There is also a power supply, a RS485 telemetry chip and connectors for future expansion. The electronics are mounted inside a 3 inch PVC pipe and fittings anchored in a bucket filled with concrete. The concrete base and Cat 5 cable are buried in the sand. The The tower sends text reports to our web space via an FTP connection using the telemetry board. The frequency of the reports starts out a one a day when the nests are new and not very active. Later the frequency increases to 6 times a day as the nest becomes more active. Since the communications tower only makes one to 6 reports a day, The microprocessor turns the telemetry board on and off, so that it consumes no power when it is not being used.

Telemetry board

We are using plug in Terminus boards made by Janus. One board works with AT&T, T-mobile and many international GSM networks. Another works with Verizon. The boards are interchangeable so both will plug into our motherboard. The cost is roughly $140 qty 1 and are available from the manufacturer, Janus. Janus has generously offered us a discount on their boards.

Hand-held registration unit

A communications board is mounted in a small hand-held unit so that it can be taken in the field when nests are first discovered. This allows park service personnel to carry just the light-weight sensors and the hand-held unit to the nest sites. Later, the much heavier and bulkier communications towers can be brought in. The Hand-Held units have GPS capability. They are programmed to test the sensors to make sure they are functioning properly, get a GPS reading, check for good cell reception, and get the local time and date from the cellular network. The date, time and GPS location are sent to the sensor, so that all this information will be available to the communications tower when it eventually connected.

Other components

The only other components necessary are the cable and connector for the turtle egg sensor, one antenna for the communications tower (the hand held unit has an extra antenna for GPS.) The units should operate for roughly 4 months running on 4 or 8 low self-discharge NiMH Batteries. Also, anyone creating these devices will need the hardware necessary for programming the microprocessors.

Cellular service

We arranged for cellular service through m2mAIR which is part of TELIT, the manufacture of the cellular modules used in the Janus plug-in boards. This service is cost effective for hosting a large number of devices, as they can all be in the same account with one monthly fee. The devices are also charged for the data used by each device, but the quota is pooled (shared) between all the devices, and the data rate charges can be modified month by month. During periods of little or no activity, the data plans can be throttled back to keep the fees to a minimum.

Web design and Database

All reports are uploaded to our web-space. The reports are comma separated text files with headings and labels, so they can be read by people as well as computers. We are beginning work on a database to store all the data. When reports are uploaded, the communications units also check the webspace for a new parameter file and download it if it is found. The parameter file has settings that effect the behavior of the devices. Here are some of the things that can be changed:

  • The frequency of reporting during inactive days
  • The frequency of reporting during active days
  • The number of inactive days
  • The number of records per report
  • How frequently samples are read by the sensor (12.5, 25, 50,100, 200 or 400 times per second)
  • All of the other settings possible for the sensor
  • Whether reports are verbose (labels on all the fields) or just data
  • Whether temperatures are calibrated

Work has started on designing a database to collect all the data in the reports, and a website to give people access to the data. This work is just in its preliminary stages in anticipation of Phase 3.

Embedded code

There are essentially three devices that need embedded code. The smart sensor, the communications tower units, and the hand-held registration units. All three of these devices use the same microprocessor, and two of them use the same circuit board. A good deal of the embedded code is shared in the three applications..

All the code was written in C using TI's Code Composer Studio which is free for developers of code that is smaller than 16K.

The code is fully documented and can be seen on GITHUB:

Parts lists

Schematics and System design

Circuit Board Fabrication

Assembly Instructions

User Guide