EE 517 Spring 2024: Instrumentation and Sensing

To keep things organized, most materials are posted on Canvas.

Design Project

Overview

The design project in EE517 is an opportunity to conceptualize a feasible wireless sensor system that can be deployed in the field and serve some purpose. In your design project final writeup and presentation, you need to answer three big questions:

  1. What data will it produce, to what degree of accuracy (e.g., the temperature will be accurate to with 0.002 °C)?
  2. What will be its SWaP-C? (Size, Weight, and Power & Cost)
  3. Why is this data source important/valuable/useful given this data rate, wireless range & datarate, SWaP-C, and battery lifetime?

Note: The answer to question 3 doesn't have to be ironclad -- you don't have to identify a market, etc., like in a startup funding pitch -- but should get you thinking about whether or not a given object is useful. For example, a temperature sensor that weighs 10 kg, lasts two hours on battery, can only transfer 1 bit every minute, and is only accurate to 10ºC is probably only useful as a doorstop.

Your project must include elements from the four major components that complement a microcontroller-based embedded system:

  1. Sensor (analog -- nothing that already speaks a digital protocol!)
  2. Interface circuit
  3. Wireless communication
  4. Energy characterization

Finally, you must show that your design is feasible. This can be demonstrated by describing that your device can be made from real (commercial, academic, rare, expensive, discontinued...) components. Include a complete bill of materials (BOM) in depth, referencing datasheets or other publications for performance calculations, and include cost estimates for major components. Minor components, such as wires and resistors, should be mentioned but specifications and costs do not need to be included. Don't forget to include an estimate about construction/fabrication/manufacturing costs and packaging size/weight/cost.

You are free to select components depending on your future career goals. Students leaning toward a career in industry might prefer to design using components that are already commercial available. Students leaning toward a career in research might prefer to design using components that have not been mass-produced but have only been written up in journal and conference papers.

If you design includes commercial components, it is expected that those components are generally available from vendors such as Digi-Key, Mouser, Arrow, Newark/Farnell/Element41, or even eBay and AliExpress. It's OK if they are out of stock or discontinued as long as you can access datasheets about their capabilities to support your performance claims. If some components are only described in academic literature, cite publications and extract relevant parameters to your analysis such as sensor sensitivity, leakage current, energy per bit, etc.

The design project should include results from hand-calculates based on values sourced from datasheets, published papers, etc., along with simulations developed in appropriate tools such as LTspice for sensor interfaces and Matlab for energy consumption estimates. Building your design is offered as extra credit, and is not required. We want to avoid limitations like supply chain availability, shipping times, costs, and hair-tearing troubleshooting to focus on what's possible with readily-available, and/or cutting-edge, technology. For those who want to build and demonstrate their design, resources such as EPL store credit may be available.

This project is limited to the simulation domain, so it is OK to end up with an incorrect analysis (e.g., noise level would actually be much higher if the system was built) as long as it's well-motivated and well-documented!

A good way to get started on the design project might be:

  1. Think of an application you know about that could be served by a sensor that periodically samples/measures some feature of its environment, wirelessly communicates and could be installed/deployed for months or longer.
  2. Identify an analog sensor that is sensitive to the environmental feature of interest. Suggested ways to find appropriate devices are to search for, e.g., "humidity sensor" on digikey.com. (If you look on sites like Adafruit and Sparkfun, be sure to keep digging into their designs until you get to the actual components they include in their boards.)
  3. Identify the rate at which the sensor needs to sample. Once per month is probably too slow and every millisecond is probably too fast, but what's the right number or range of numbers?
  4. From here, other parameters like wireless communication power and range, intended battery life, weight, might start to be more clear.

The three-stage Design Project lifecycle in EE517 is lightly modeled on Department of Defense design reviews. Those are documented in more detail in such places as:

https://swehb.nasa.gov/display/7150/7.9+-+Entrance+and+Exit+Criteria https://en.wikipedia.org/wiki/Design_review_(U.S._government) https://resources.sei.cmu.edu/asset_files/TechnicalNote/2006_004_001_14708.pdf

The design project is an individual assignment.

Stage 1: Pitch (Typically during Week 4)

(15 points presentation, 5 points peer evaluations, 5 points self-evaluation)

Prepare a 3-4 minute "pitch" conceptual presentation to the class about your project. Three slides maximum. Slides must be added to one class-wide Google Slides presentation prepared by Dr. Burnett (link posted to Canvas). We are strictly limited on time, so presentations can not last longer than 4 minutes.

In your pitch, include the following (one item per slide is probably a good idea):

We won't have made it through a lot of the necessary course material by the time you need to prepare for this pitch. That's OK, because you will better identify how later course material fits in to the design project as it is introduced later on.

All students are also required to provide brief feedback to each presenter about their pitch. A form to provide feedback will be provided by Dr. Burnett.

Stage 2: Intermediate Update (Typically during Week 8)

(8 points presentation, 2 points peer evaluations, 15 points written document)

To be added.

Stage 3: Final Project (Typically during Finals Week)

(20 points presentation, 5 points peer evaluation, 25 points final report)

To be added.