Bluetooth Unleashed Design Challenge: Example Application

randogless — Mon, 30 Apr 2018 14:43:50 GMT

Current Revision posted to Documents by randogless on 4/30/2018 2:43:50 PM

The key to a great application is to provide as much meaningful information about your proposed project as possible.

It should provide the judges that you have an understanding of the problem you are going to solve, a design plan, how the kit will be used, images, drawings, rough sketches, and how you will solve the problem. Adding your past involvement in Design Challenges or RoadTests should also be included. You should also include a short bio on your professional background.

Below is an application example from community member Douglas Wong for the Safe and Sound Design Challenge.

Safe and Sound Design Challenge Application: Invisible Hazardous Environmental Factors Monitoring System (IHEF)

The first step in becoming safe and sound is to know the dangers and risks. Then we can devise strategies to stay safe and sound. This project investigates what invisible environmental factors might have hazardous side effects, how we might detect these conditions and what we can do to minimize the risks.

Are you worried about the side effects of being near power lines?

Are you worried about the possible side effects of cell phone radiation?

Are you worried about Wi-Fi radiation?

Are you worried about stray radiation from your microwave oven?

Are you worried about radon gas?

Are you worried about high levels of CO₂ or low levels of oxygen in the air you breathe?

Most people are aware that there are numerous invisible environmental factors that are potentially dangerous to humans, and many of us have nagging concerns that we are being exposed to potentially dangerous levels without knowing about it.

This project is not any kind of scientific medical study, it just explores how we might attempt to monitor some potentially dangerous environmental factors that cannot be detected by human senses. It will also discuss health risks filtered from information on the internet and provide some techniques we can use to minimize risks and exposure.

This project has been on my to-do list for a long time and this challenge is a good catalyst to place a completion schedule on it, not only for my own benefit, but for all those who are also concerned or curious about these potential health risks.

The Problems

Light

When people think of dangerous radiation, they don't usually think of light, but the most common adverse health effect due to radiation is sunburn - from ultraviolet light. Excessive UV exposure can also lead to skin cancer. UV radiation is divided into wavelength ranges identified as UVA (315 to 400 nm), UVB (280 to 315 nm), and UVC (100 to 280 nm). Of the solar UV energy reaching the equator, 95% is UVA and 5% is UVB.

UVC is so energetic it gets absorbed in the atmosphere and never reaches the planet surface. UVB is both good and bad for people – it helps us synthesize the extremely important hormone called vitamin D, but can also damage DNA - leading to health problems.

Microwaves

Cell phones generally include 3 microwave transmitters - Wi-Fi, cell phone, and Bluetooth – how dangerous are these microwave emissions? How can we reduce our exposure and health risks? Other devices in this category include tablets, Wi-Fi routers and microwave ovens.

There is significant ambiguity around possible carcinogenic effects of cell phones, possibly because it may take 40-50 years to have conclusive statistics. The risk of cancer from microwave radiation is probably increased by our lifestyle, but still a small risk.

However, cancer isn't the only potential risk - there is already fairly conclusive evidence that cell phone emissions adversely affect reproduction in humans, but how severe is it? I will review what is “known”, and what can be done about it. I will also explore how to measure cell phone emissions and determine when cell phones are transmitting at high power. We don't want to give up the benefits of cell phone technology, so how do we keep the benefits and minimize the risks.

Radioactive Radiation

Radon Gas – How prevalent are dangerous levels of Radon and what can we do to reduce exposure? Radon is everywhere but at different concentrations, so the question is what level is acceptable? The US EPA has set a level of 4 pCi/L, beyond which corrective measures should be taken, but this level is still estimated to represent a far higher risk of lung cancer than the risks allowed for carcinogens in food. 4 pCi/L over 48 hours is equivalent to 8.88 particle decays per liter per minute. These decays eject alpha particles (helium nuclei) at 15,000 m/s and result in other radioactive particles like Polonium that will in turn eject more alpha particles, all of which can damage lung tissue. Assuming we want to have the least exposure to high energy alpha particles, what steps can we take? I will explore how Radon levels are measured and mitigated.

Invisible Gases

Carbon Dioxide – How do we know when we are exposed to excessive levels and what can we do about it. Outdoor concentrations of CO2 range from 350-400 ppm or higher if combustion engines are present. Indoors the concentration can rise if fresh air infusion is not adequate. ASHRAE recommends 17 cubic feet of fresh air per minute per person to keep CO2 below 1000 ppm. Adverse symptoms can appear at concentrations of 5,000 ppm, although it is not considered unsafe until concentrations exceed 10,000 ppm. I want to get a feel for the concentration levels where I live and work and figure out how to ensure enough fresh air.

Carbon monoxide – CO is another gas that can be dangerous without us being able to detect it. By contrast, oxygen levels can become dangerously low but equally undetectable. Some dangerous volatile hydrocarbons are also not easy for people to detect.

Low Frequency Magnetic and Electric Fields

High voltage power lines – What are the dangers of proximity to high voltage power lines and how much exposure is acceptable? There have been hundreds of reputable studies performed all over the world to determine the health effects of proximity to power lines. It is possible to find good studies that will validate just about any opinion from completely benign to virtually suicidal, but about two thirds of the studies find a definite link between power line proximity and adverse health effects. Since the majority of researchers conclude it is not healthy to have extensive close exposure to power lines, I want to figure out what that means. We all live near power lines of some sort, only the voltages and proximity are quite variable. I want to get some idea for example how the field 500 m from a high voltage line compares to the field 1 m from a 220 V line.

Other electronic devices – There are any number of other electronic devices that may emit harmful radiation, such as induction cooking ranges. I want to perform an audit of all the electrical devices in my life to determine which have significant emissions. Since starting to research for this project I have already made some surprising discoveries.

The Project Plan

Research

The problems addressed by the project will be researched

The instrumentation that is needed to quantify the problems will be researched and selected

The challenge kit of parts will be researched with respect to using them in the project

System Design

Block diagram

PCB Design

Wearable Chassis design

Software Design

Power supply design

Material Procurement

Material needed for the project will be sourced and procured

System Build

Electronics build, Mechanical Build, Software programming

Developmental Testing

System electrical testing, System software testing, System mechanical testing

System Application Tests

The system will be used to audit my environment

Documentation & Conclusions

Each of the project plan tasks will include a related blog

System Concept

The instrumentation that I am proposing to use to monitor the invisible entities outlined above takes up a considerable amount of physical space, as does the supplied kit of modules to be used in the challenge. It could easily fill up a backpack, but in order to better meet the wearable requirement, I will package all the instrumentation in a forearm-mounted “sleeve”. Although it will be too large for everyday wearing, I want to make it wearable, useful, ergonomic and aesthetically professional looking. The plan is to have 4 displays, a touch pad, and UV sensor lined up along the top of the forearm, one of the displays will be the Sharp graphics LCD that is part of the challenge kit.

Display 1 - α, β, γ, x-radiation
Display 2 - EMF (ELF magnetic field, electric field, & RF)
Display 3 - microwave & RF field strength
Display 4 - UV & air quality (O2, CO2, CO, VOC)

Along the inside of the forearm will be the computer module and Wi-Fi Booster (parts of the challenge kit).

Along the outside of the forearm will be a suite of environmental sensors.

On the underside of the forearm will be the battery and power supplies.

At least 2 of the instruments will need mechanisms to fold away when not in use. Each folding mechanism requires five 3D printed parts.

At least 10 of the modules will require 3D printed cases to mount on the sleeve, where each case may need 2 or more 3D parts.

Aside from 3D parts, the mechanics of the system will need some soft goods, pads and straps to attach comfortably to a forearm.

Electrically the air quality sensor suite will require a custom PCB to turn them into a module. Firmware will be needed to read and display sensor data, and I would like to publish the data on an MQTT broker since the kit includes a Wi-Fi module. Hopefully I can use a Raspberry Pi as the MQTT broker.

Credentials

I have participated successfully in several element14 design challenges and complex Road Tests. These projects are referenced to demonstrate how fully I participate in Design Challenges, my level of technical capabilities and the diligence of my blog postings.

Summary & Notes

This wearable environmental factors instrumentation system is a fairly ambitious project with many challenges, but I find the subject matter and chance to learn and stretch my capabilities very motivating. Although there will be a lot of work associated with sourcing and procuring instrumentation, learning device characteristics, designing and building hardware and programming firmware, most of it is the type of engineering I am familiar with. The main risks for me are learning and trusting other people's software, such as MQTT broker software, but it is a good opportunity to explore this interesting technology.

There is a significant problem in finding low cost sensors that will interface to a computer while providing reasonable data, so part of this project is a fairly comprehensive search for suitable instrumentation. This has already been researched enough to build the above block diagram, however there are a lot of peripherals in the plan and I have not done enough detailed design yet to know if there are enough pins on the MCU to interface with all of these devices. There are 4 Booster packs from the supplied kit in my block diagram but I'm not sure even these can all work together – they certainly don't look stackable.

I still expect the design challenge modules kit should make a fine wearable platform with an MSP-EXP432P401RMSP-EXP432P401R MCU a CC3100MODBOOSTCC3100MODBOOST Wi-Fi link and a 430BOOST-SHARP96430BOOST-SHARP96 LCD forming the core platform. The core platform can always be extended as new peripherals become available or feasible. This is an exciting design challenge that fits well with my interests in wearable technology and IoT. I have already benefited by doing fairly extensive research and conceptual design for this proposal.

Tags: bluetooth_unleashed, design_challenges