Design Document

Description

The design document communicates the complete and detailed design of your project. It is substantially more detailed than the proposal and prepares you for the assembly phase of the semester. A quality design document is the key to a successful project (sample document). Use the following format:

  1. Introduction

    • Problem and Solution:

      One to two paragraphs explaining the context of the problem to be solved by your project, including any relevant references to justify the existence and/or importance of the problem (i.e., the need or want for a solution). Justify the novelty of your solution or explain the expected improvements of your solution over previous results.

    • Visual Aid

      A pictorial representation of your project that puts your solution in context. Not necessarily restricted to your design. Include other external systems relevant to your project (e.g. if your solution connects to a phone via Bluetooth, draw a dotted line between your device and the phone). Note that this is not a block diagram and should explain how the solution is used, not a breakdown of inner components.

    • High-level requirements list:

      A list of three to four objective characteristics that this project must exhibit in order to solve the problem. These should be selected such that if any of these requirements were not met, the project would fail to solve the problem. Avoid vague requirements that can be interpreted a number of ways (e.g. "The radio subsystem should work reliably."). Each high-level requirement must be stated in complete sentences and displayed as a bulleted list.

  2. Design

    • Block Diagram:

      A general block diagram of the design of your solution. Each block should be as modular as possible and represent a subsystem of your design. In other words, they can be implemented independently and re-assembled later. The block diagram should be accompanied by a brief (1 paragraph) description of the critical subsystems and what they do.

    • Physical Design (if applicable):

      A physical diagram of the project indicating things such as mechanical dimensions or placement of sensors and actuators. The physical diagram should also be accompanied by a brief one paragraph description.

    • [Subsystem X]

      For each subsystem in your block diagram, you should include a highly detailed and quantitative block description. Each description must include a statement indicating how the block contributes to the overall design dictated by the high-level requirements. Any and all design decisions must be clearly justified. Any interfaces with other blocks must be defined clearly and quantitatively.

      Include any relevant supporting figures and data in order to clearly illustrate and justify the design. Typically a well justified block design will include some or all of the following items: Circuit schematics, simulations, calculations, measurements, flow charts, mechanical diagrams (e.g. CAD drawings, only necessary for mechanical components).

      You must include a Requirements and Verifications table. Please see the R&V page for guidance on writing requirements and verification procedures.

    • [Subsystem Y]

      ...

    • [Subsystem Z]

      ...

    • Tolerance Analysis: Through discussions with your TA, identify the block or interface critical to the success of your project that poses the most challenging requirement. Analyze it mathematically and show that it can be feasibly implemented and meet its requirements. See the Tolerance Analysis guide for further guidance.
  3. Cost and Schedule

    1. Cost Analysis: Include a cost analysis of the project by following the outline below. Include a list of any non-standard parts, lab equipment, shop services, etc., which will be needed with an estimated cost for each.
      • Labor: (For each partner in the project)
        Assume a reasonable salary
        ($/hour) x 2.5 x hours to complete = TOTAL
        Then total labor for all partners. It's a good idea to do some research into what a graduate from ECE at Illinois might typically make.
      • Parts: Include a table listing all parts (description, manufacturer, part #, quantity and cost) and quoted machine shop labor hours that will be needed to complete the project.
      • Sum of costs into a grand total
    2. Schedule:

      Include a time-table showing when each step in the expected sequence of design and construction work will be completed (general, by week), and how the tasks will be shared between the team members. (i.e. Select architecture, Design this, Design that, Buy parts, Assemble this, Assemble that, Prepare mock-up, Integrate prototype, Refine prototype, Test integrated system).

  4. Discussion of Ethics and Safety:

    1. Expand upon the ethical and safety issues raised in your proposal to ensure they are comprehensive. Add any ethical and safety concerns that arose since your proposal.
    2. Document procedures to mitigate the safety concerns of your project. For example, include a lab safety document for batteries, human/animal interfaces, aerial devices, high-power, chemicals, etc. Justify that your design decisions sufficiently protect both users and developers from unsafe conditions caused by your project.
      Projects dealing with flying vehicles, high voltage, or other high risk factors, will be required to produce a Safety Manual and demonstrate compliance with the safety manual at the time of demo.
  5. Citations:

    Any material obtained from websites, books, journal articles, or other sources not originally generated by the project team must be appropriately attributed with properly cited sources in a standardized style such as IEEE, ACM, APA, or MLA.

Submission and Deadlines

Your design review document should be uploaded to PACE in PDF format by the deadline shown on the course calendar . If you have uploaded a mock DR document to PACE, please make sure that it has been removed before DR.

Low Cost Distributed Battery Management System

Logan Rosenmayer, Daksh Saraf

Low Cost Distributed Battery Management System

Featured Project

Web Board Link: https://courses.engr.illinois.edu/ece445/pace/view-topic.asp?id=27207

Block Diagram: https://imgur.com/GIzjG8R

Members: Logan Rosenmayer (Rosenma2), Anthony Chemaly(chemaly2)

The goal of this project is to design a low cost BMS (Battery Management System) system that is flexible and modular. The BMS must ensure safe operation of lithium ion batteries by protecting the batteries from: Over temperature, overcharge, overdischarge, and overcurrent all at the cell level. Additionally, the should provide cell balancing to maintain overall pack capacity. Last a BMS should be track SOC(state of charge) and SOH (state of health) of the overall pack.

To meet these goals, we plan to integrate a MCU into each module that will handle measurements and report to the module below it. This allows for reconfiguration of battery’s, module replacements. Currently major companies that offer stackable BMSs don’t offer single cell modularity, require software adjustments and require sense wires to be ran back to the centralized IC. Our proposed solution will be able to remain in the same price range as other centralized solutions by utilizing mass produced general purpose microcontrollers and opto-isolators. This project carries a mix of hardware and software challenges. The software side will consist of communication protocol design, interrupt/sleep cycles, and power management. Hardware will consist of communication level shifting, MCU selection, battery voltage and current monitoring circuits, DC/DC converter all with low power draws and cost. (uAs and ~$2.50 without mounting)