Unit Testing
Testing and verification of modules in your system is important to understand whether or not your design matches or will match up with your requirements. There are a number of different methods that involve testing, you should be able to identify which type of testing applies to each design requirement or attribute.
Testing Types
There are five types of unit testing that we will consider in this topic. It is likely for your project, that only the first three are relevant:
- Analytical testing, such as using analytical models (CAD, CAM) or textbook equations
- Proof-of-concept testing (Type I), such as using breadboards, mock-ups and rapid prototyping
- Model(/prototype) testing (Type II), such as the construction of prototype
- Operational testing (Type III), for when the design introduced into the field
- Support testing (Type IV), for when the design is in operational use
For your project, Operational and Support testing are likely to be sometime into the future if the project continues. At this stage of your project, you should almost certainly be able to engage with Analytical and Proof-of-concept testing.
Goals for this topic
Depending on the scope and progress of your project, your goals at this stage will be different. The purpose of testing in this course is to demonstrate to your client that they should have confidence in your work.
- at minimum, design a test procedure for a subsystem or function in your design at a future proof-of-concept stage
- if possible, demonstrate how your design will complete an analytical test. For example, using basic physics equations, or computer aided design, models, schematics to demonstrate how the proposed design will function
- if possible, demonstrate at a proof-of-concept level that a subsystem functions as expected. For example, a breadboard design of a single subsystem or function
Steps
A test design should include:
- A descriptive title, test scope, version number of the test, and responsible officer
- Any specialist terminology or calculations required for interpreting the test
- The procedure, apparatus and safety measures
- Analysis and interpretation of the results
Hints
- Just like the experimental method, tests should be robust, objective and repeatable.
- Document your test procedure and results, and use the results in your evaluation process.
Core resources
- Blanchard, B.S., W.J. Fabrycky, Systems Engineering and Analysis, Fifth ed. Pearson, New Jersey, 2011. Testing types [PDF, pp166-171]
- Australian Design Rules examples of design standards of cars [Third Edition ADRs, look up some ADRs to get an understanding of testing procedures, eg: ADR 4/00 Seatbelts, ADR 6/00 Direction Indicators, ADR 79/00 Emissions Control for Light Vehicles]