Project Terminated Due to Covid Pandemic

 Unfortunately, this project had to be terminated before completion due to the Covid 19 Pandemic closing down schools in March for 14 days and later for the rest of the school year. I feel the students were on track to complete a functional prototype in a normal school year. I would like to thank all the students and community members, sponsors and mentors who helped with this project.

Workday 3.9.2020

Date: 3.9.20

Location: Logan High School

Time: 12:00-2:00 PM

Goals: AMP chip circuit design, continue working on the sensor/circuit board housing design.

Students: Tommy, Abie, Clara, Rebecca, Sam, Ella

We continued working on the housing for the sensors and circuit boards today with plans to 3D print the design. Abie and Rebecca are looking at a design where the circuit board slides into the housing. Hose and wires will be routed out on opposite sides of the enclosure.

Clara, Ella and Tommy  began working on the circuit and design for the AMP Chip (LMV 321). The purpose of this circuitry is to boost the signal so the software can better define its resolution. This process included soldering 5 small wires together onto the chip. It was a very long and tedious task because everything is very small. We decided to order a bread board to hold the chip in place that will make the surface mount process easier. We will order a surface mount board for next week to speed this up. It is taking too long to solder the surface mount chips.

On the software side of things, Sam started working on getting an output to an app which he was successful in doing on a small scale. Now he needs it to be displayed in a graphically pleasing form on the App.

Next week we will work on getting some readings with the sensors in a pack and getting some pressure on them. We will also try out the 3d printed housings.

Tommy working on Multisim for the AMP circuit design.

Abie and Rebecca working on designing the circuitry housing.

Clara learning to solder surface mount.

Some fine soldering work.

Workday 3.3.2020

Date: 3.3.20

Location: Logan High School

Time: 10:00-12:00

Goals: Work more on designing sensor housing, connect the software up to the sensors on the bladder

Students: Tommy, Abie, Sam, Will, Ella

During this meeting we worked more on designing housing for the sensors and electronics as well as connecting the software up to the sensors. Once the software was connected, we once again put different amounts of water into the Camelbak and this time, we got the data through our software.

We also worked on finding an equation for the amplifier circuit that we will need to build. This may be neccessary to amplify and clean up the inputs that the Arduino receives. If so, it will have to be designed into the existing circuit board.

It was a fun day today and we got donuts!

Students conneting the pressure sensors to the software.

Sam demonstrating that the software is interfacing with the hardware sensors.

Mr. Foye and Ella working out the math equation for the amplifier circuit. 

Worknight 2.25.2020

InvenTeam Worknight

Date: 2.25.20

Location: Logan High School

Time: 4:30-6:30

Goals: Continue testing the sensors, determine baselines for the software, and begin working on ideas for protecting the sensors and electronics 

Students: Tommy, Abie, Clara, Sam, Rebecca, Will, Ella

Today we continued our work on the sensor circuit boards and tested the second board for functionality. We attached the two sensors to the top and bottom of the Camelbak and took pressure readings with different amounts of water, in different positions, and with different amounts of pressure on the bladder. We also discussed ideas for securing and protecting the sensors and electronics. We thought about questions like how will the sensor be mounted on the Camelbak? Where will it be mounted?

We determined the baseline readings needed for the software. Our first priority readings were: empty bladder (0% full), half full (50% full), full (100% full). Our second priority readings were bladder compressions, which we can get from repeating tests we have done previously. Another question that came up was how will this monitoring system be powered?

We discussed multiple possibilities like batteries and batteries that can be solar powered.

Because our team shirts came in last week, we ended the work night with a team photo!

Notes from Abie and Rebecca: Circuit Board and Plumbing Packaging 

Problem: We need to design an enclosure that protects two circuit boards and a battery pack. 

• Enclosure 

• Snap-together plastic enclosure/box sealed with o-rings
• Use inventor to design box, purchase o-rings and other parts 

• 2 Different boxes vs one big box 

• House both boards in one box, use tubing to connect top and bottom to meet with one big box 
• Tubing 
• Where would we put the sensor connections for the tubes?

• Having the tube on the twist opening would make things difficult when opening the bladder
• Run two tubes through one fitting, allowing for one central location for the box
• Where would we disconnect the tube to attach to the box?
• Use one connection with one long piece of tubing permanently connected to the box
• Use two connections, a tube to connect to the bag and a tube to connect to the input on the box

• Location of box(s)

• Run tubes into a more accessible location in backpack

• Makes the battery pack accessible and isolated from water

• Where do we attach the box?

• Cut out a section of the backpack to place it
• Make the enclosure have the ability to be removed from the backpack/bladder
• Use velcro to remove
• Use some sort of clip
• How do you make the box compatible for different backpacks or bladders?
• Make the design limited to only one backpage and bladder size
• Concept A
• Mount the box permanently in the backpack, in the same compartment as the bladder
• Pros: The tubes are in the same same compartment as the bladder
• Cons: The circuit could get wet because it is close to the bladder 
• Concept B
• Mount the box in an isolated compartment as the bladder
• Pros: It would prevent the circuit from getting wet
• Cons: You would need to cut through the backpack to connect the sensor tubing to the box

Dimensions of circuit board

Length - 8.5cm

Width - 3.2

Height - 2.2

9 Volt Battery

Tube size 3mm or ⅛ In

Sam and Will working on programming parameters.

Tommy and Clara and Mr. Foye bench testing the two sensors before doing a water volume test.

Rebecca and Abie working with Mr. Butterworth on a housing for the electronics.

Our first water volume test with both sensors implemented.

In one part of the test we used a book as a weight to see if compression effected the pressure readings.

The 2019-20 Logan InvenTeam

Worknight 2.18.2020

InvenTeam Worknight

Date: 2.18.2020
Location: Logan HS
Team members: Rebecca, Tommy, Sam, Will and Clara.
Goal: Go over alternate mechanical design and work on circuit boards and programming

We handed out the new t-shirts tonight and everyone seemed to like them.

Mr. Butterworth (Mechanical Engineer) offered an alternate solution to the pressure sensors we are working on now which included the use of a manometer. We will continue to work on the pressure sensor idea and test it and then determine if we need an to move in this direction. Rebecca worked with Mr. Butterworth on refining that concept.

Mr. Foye worked with Clara on how to use a DC power supply and tested out the circuit boards that we hastily soldered together today in order to test them tonight. We has some problems with the actual circuit board and soldered components connecting to it. It seemed we had to heat up those solder joints quite a while.

Bench testing went well with the circuit boards. We went slowly from 0 -7 V to test the regulator. It output a steady 5 V which is what we need. Then we applied a voltage to the transducer and it output the 2.5 V specified. We then blew into a piece of surgical tubing to test the sensor and it output a varied voltage which is what we want. One board is completed and tested and we went right to work on the other one which had a resistor problem.

The progress was very good on the circuit boards tonight. There was a concern if we could get them completed, but we only have one or two more solder connections on the second board to finish.

Tommy worked on a testing regiment for the sensors and found some interesting data. The sensor registered no difference when the vent was close or open on the top of the bag. When we get the other sensor up and running next week we should start to see a pressure difference.

Team members working with local engineering consultants on different parts of the project.

Mr. Foye and Clara working on bench testing the circuit boards.

Will and Tommy working on testing the lower sensor.

Worknight 2.11.2020

Date: 2.11.20

Location: Logan High School

Time: 4:30-6:30 PM

Goals: Continue working on circuit boards, begin planning an experiment

Students: Tommy, Abie, Clara, Sam, Will, Ella

Fun news from today’s meeting: our t-shirts should be here next week!

We talked about the pressure within the bladder as the water level decreases. In order to figure out what will go on inside of the bladder as the water levels change, we need to conduct a detailed experiment. The bladder is flexible and can change shape as it gets filled or emptied. We need to find a way to measure that. We also need to determine what we are going to consider as “full.” How much water are we putting into the bladder? This measurement should be consistent when experimenting. Our goal for the experiment is to find a function that will tell us the volume of water. Our team broke up into three groups; one group worked on the circuit boards, the second worked on the programming needed for later on, and the third worked on preparing the experiment.

Circuit board work came along slowly. We had a few desolders and questions on schematics. We hoped to be done with this tonight and we were not. Software is moving forward with a successful test of Bluetooth communication link between phone and microcontroller and then with a potentiometer test where we saw an output registered on the phone. This is nice progress on the coding end.

Tommy and Clara working on soldering the circuits boards.

Will and Sam working on code to interpret sensors.

Mr. Butterworth (retired Mechanical Engineer) looking over the CamelBak for sensor hose locations.

Video of the microcontroller outputing a signal to a phone.

Worknight 2.4.2020

Date: 2.4.2020
Location: Logan High School
Time: 4:30-6:30 PM
Goal: See list below
Students: Tommy, Abie, Clara, Sam, Rebecca, Ella

Worknight Goals:
1. Parts/components order update
2. T-shirt update
3. Hosebarbs inserted in hydration bladder overview
4. Use force plate to measure mass of hydration bladders
5. Sensor/circuit board design/fabrication -Mr. Foye
6. Manometer spreadsheet explanation -Mr. Foye
7. Wrap up and order any needed components

Today we took a deeper look into a few different pressure sensors by discussing the pros and cons of each sensor and how each could work with our project. After careful consideration, we decided on one of the sensors to begin working with. We also talked about soldering the sensor to a breadboard instead of soldering the wires directly onto the sensor. This will result in more stability and at this time, we are not as concerned about our monitor being small as much as we are concerned with it working well. Along with the sensor we want to solder the regulator onto the breadboard. We began soldering the sensor to the breadboard and constructing our experimental model. An LED is going to be added so that we know when it is working.

A home made manometer to double check our sensor readings.

Students working on soldering the sensor circuit.

Rebecca working on breadboarding a wireless module.

Sam working on the Arduino interface.

More time soldering the sensor circuit. Some problems with our prototype boards.

Sensor circuit diagram complete with a ballast resistor.