MCF > Integration and Test >
Electronics Functional Testing
Scope and Description
This topic covers functional testing of electronics, which refers to comprehensive testing that verifies that the assembled system meets all functional requirements. Functional testing verifies all parametric performance specifications under all required operating modes of the electronics. Functional testing is the most fundamental and therefore important test because most other testing depends on it. Functional testing is typically performed a number of times on each unit to fully verify performance following manufacturing processes, after tests to check for damage (e.g., vibration or total ionizing dose), and during tests to verify performance over temperature (e.g., thermal cycling).
Resources under this topic area are primarily examples of electronics functional testing for smallsat systems.
Best Practices and Lessons Learned
- A comprehensive functional test is essential to reliability. The design team should be closely involved in developing this test and verifying that all operational corner cases are included.
- Because functional testing will be repeated many times on each unit and because it is often a relatively complicated test, consider investing extra time and equipment to optimize it for efficiency and repeatability. Fully automated testing is very expensive up front, but could make sense in the long-run.
- Trend functional test data for each unit and between units to look for outliers in each measurement. This could detect workmanship flaws or damage during manufacturing or test that is not detected by the functional test itself.
- Avoid skipping any functional tests. Instead, consider developing a shorter version. For example, consider running a full functional test after assembly, the shorter functional test during environmental testing, and then the full functional again test prior to integration.
"This Standard establishes the environmental and structural ground testing requirements for launch vehicles, ... upper-stage vehicles, space vehicles, and their subsystems and units. In addition, a uniform set of definitions of related terms is established."
This thesis described automated functional testing of the MIniature Student saTellite (MIST) cubesat ... and of various MIST electronic subsystems. This thesis is not comprehensive, as indicated by the significant "future work" that is required to complete implementation of the proposed solutions for automated functional testing. However, it provides valuable, detailed background and design information to inform the design and development of smallsat automated test procedures and low-cost test equipment.
This thesis provides a description of the functional testing of the MIniature Student saTellite (MIST) ... cubesat electrical power system (EPS). This includes the development of custom, low-cost test equipment, test procedures, and results.
This presentation slide deck provides an overview of a typical "in-house" NASA integration and test program. ... This includes I&T definitions, processes and procedures, roles and responsibilities, and facility considerations.
Zachary Scott Decker
This thesis provides a detailed review of testing, failures, and costs of cubesat programs and how strategies ... can be improved to ensure smallsat mission success. It focuses on how to develop low-cost cubesats with reduced risk by implementing a design and build strategy along with thorough testing.