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In sectors such as automotive, aerospace, and consumer electronics, electronic measurement equipment must endure various environmental conditions, including mechanical shocks. These shocks, resulting from events like drops, impacts, and sudden accelerations, pose significant risks to equipment reliability and data integrity. This case study outlines a comprehensive mechanical shock testing strategy designed to ensure durability, accuracy, and longevity in electronic measurement equipment used in harsh environments.

Objectives

The primary goals of this mechanical shock testing strategy are to:

1. Validate Equipment Reliability: Ensure that measurement equipment can withstand specified shock events without damage or performance degradation.
2. Maintain Measurement Accuracy: Confirm that data integrity is preserved under shock events, especially for critical components such as sensors and circuit boards.
3. Identify Weaknesses: Detect potential points of failure to inform design improvements and mitigate shock-induced risks.

Strategy Overview

The mechanical shock testing approach is divided into several phases:

1. Pre-Test Analysis and Preparation
• Component Identification: Identify sensitive components prone to shock damage, such as accelerometers, gyroscopes, and printed circuit boards (PCBs).
• Environmental Conditions: Define operational conditions, including temperature, humidity, and pressure, to simulate real-world application environments.
• Shock Profiles: Develop shock profiles based on application requirements (e.g., military standards like MIL-STD-810G or automotive standards such as GMW3172), including shock magnitudes, durations, and frequency ranges.
• Fixture Design: Design fixtures that securely hold equipment without damping the shock response.
2. Mechanical Shock Testing Types
• Half-Sine Shock Pulse Testing: Useful for simulating drop impacts, this test applies a half-sine shock pulse to replicate sudden forces on the equipment. The shock duration and peak acceleration are tailored based on field data or industry standards.
• Trapezoidal Shock Pulse Testing: This test is beneficial for components that undergo sustained forces, delivering a constant acceleration level over a specified time.
• Random Shock Environment Simulation: Simulates multiple shock events over an extended period to evaluate cumulative damage. Ideal for equipment that might experience repetitive shocks over its lifespan.
3. Test Execution
• Baseline Measurements: Record initial data from the equipment to serve as a baseline. This includes calibration data, noise levels, and signal integrity parameters.
• Shock Application: Apply shocks according to the defined profiles. The shock pulse application can be done using an electrodynamic or servo-hydraulic shaker, tailored to handle the desired acceleration and frequency ranges.
• Data Acquisition: Measure parameters such as peak acceleration, displacement, and response time to understand how each component responds to shock forces.
• In-Test Monitoring: Use real-time monitoring systems to detect any deviations in equipment performance during shock application, focusing on signal output stability and structural response.
4. Post-Test Analysis
• Functional Verification: Check for functional anomalies in components, specifically examining areas prone to failure (solder joints, connectors, etc.). Any degradation in signal output or increased noise is flagged.
• Visual Inspection and X-Ray Imaging: Inspect for cracks, delaminations, or loose connections. X-ray imaging can reveal hidden issues, such as micro-fractures or solder joint failure.
• Re-Calibration: If calibration drifts are observed, recalibrate the equipment to assess whether its accuracy remains within acceptable limits.
• Failure Mode Analysis: Conduct root-cause analysis on any identified failures to inform redesign efforts.
5. Documentation and Reporting
• Test Summary Report: Compile a report detailing test conditions, shock profiles, data from baseline and post-test measurements, and any observed anomalies.
• Lessons Learned: Document insights from failure analysis and design recommendations.
• Redesign Recommendations: Based on findings, suggest design improvements, such as component reinforcement, shock-absorbing materials, or modified mounting strategies.

Key Findings and Recommendations

In implementing this strategy for electronic measurement equipment, several insights emerged:

• Component Reinforcement: Sensitive components, like accelerometers and PCBs, often required additional reinforcement. This included using epoxy adhesives on vulnerable connections and incorporating shock-damping materials in high-risk areas.
• Mounting Optimization: A redesign of the mounting fixtures allowed for better energy distribution, reducing the risk of localized stress that could lead to component damage.
• Enhanced Calibration Procedures: Regular recalibration protocols post-shock testing minimized data drift, ensuring accurate measurements in field applications.
• Material Selection: Shock-absorbing materials, like rubberized coatings, reduced the peak forces transmitted to delicate components, thus increasing durability.

Project Leader: Tom Resh

Project duration: 6 Months

Background

In space applications, printed circuit board assemblies (PCBAs) face extreme temperature fluctuations due to limited atmospheric insulation and the high-radiation environment. These factors elevate the risk of overheating in critical components, which can lead to failures that jeopardize the mission. This case study details a comprehensive thermal testing approach for identifying, mitigating, and eliminating overheating failures in a critical component on a PCBA designed for a spacecraft application.

Objectives

The primary objectives of this thermal testing strategy are to:

1. Prevent Overheating: Identify and eliminate potential overheating issues that could lead to component failure.
2. Ensure Thermal Stability: Verify that the component maintains stable performance across a range of thermal conditions that simulate the spacecraft’s orbit and mission environment.
3. Optimize Component and PCBA Design: Provide insights for design improvements to enhance thermal resilience.

Strategy Overview

The thermal testing approach consists of four main phases: Thermal Simulation, Pre-Test Analysis, Thermal Testing Execution, and Post-Test Analysis.

1. Thermal Simulation and Analysis

To anticipate thermal behavior and design initial mitigations, a thermal simulation was conducted using computational fluid dynamics (CFD) and finite element analysis (FEA).

• Thermal Modeling: Simulations identified hotspots on the PCBA, particularly around a voltage regulator and a power MOSFET. These areas were flagged for intensive testing.
• Simulation of Mission Conditions: Thermal simulations modeled the vacuum of space and the full temperature range expected during orbit. Thermal cycling between -150°C and +125°C was applied based on mission requirements to simulate temperature swings experienced in space.
• Design Recommendations: Initial recommendations included heat sinking, component re-positioning, and the addition of thermal vias for more efficient heat distribution.

2. Pre-Test Analysis and Setup

Component Identification and Monitoring Setup: Key components on the PCBA, such as power transistors, voltage regulators, and microcontrollers, were equipped with thermocouples to measure real-time temperature during thermal testing.

Thermal Test Chamber Calibration: A thermal vacuum chamber (TVC) was calibrated to replicate the thermal and vacuum conditions of the space environment. The chamber was set up to control both temperature and pressure, ensuring that heat dissipation mechanisms, such as radiation, accurately reflected the spacecraft’s conditions.

Baseline Functional Testing: Before thermal testing, functional tests were conducted on the PCBA to establish a baseline performance profile. Parameters like output voltage, signal stability, and response times were recorded.

3. Thermal Testing Execution

The testing phase consisted of several distinct thermal stress tests to identify potential overheating issues:

1. Thermal Cycling and Soak Test:
• Procedure: The PCBA underwent multiple thermal cycles from -150°C to +125°C. Each cycle included a soak period at peak temperatures to test the component’s endurance and thermal response.
• Objective: This test aimed to observe whether thermal stress caused performance drift or degradation in components over extended temperature fluctuations.
2. Thermal Ramp Stress Testing:
• Procedure: The temperature was ramped up at an accelerated rate to the upper limit of 125°C while the components were monitored for excessive heat rise.
• Objective: The purpose of this test was to identify weak points in the component layout that might lead to thermal runaway during rapid temperature changes.
3. Thermal Shock Testing:
• Procedure: The PCBA was subjected to rapid transitions between -150°C and +125°C. This test involved sudden exposure to extreme temperatures to mimic abrupt shifts from sunlight to shadow during orbit.
• Objective: To validate the component’s ability to maintain stable performance and avoid cracking, delamination, or thermal-induced stress fractures.
4. Operational Thermal Load Testing:
• Procedure: The component was powered and operated at full load within the thermal vacuum chamber to simulate active mission conditions. Monitoring included continuous thermal imaging and current measurement to detect signs of overheating.
• Objective: This test replicated operational heat generation within the PCBA, focusing on identifying components that might overheat under load.
5. Extended Duration Soak Test at Critical Hotspot:
• Procedure: After thermal cycling, a prolonged soak at 115°C (slightly below the max temperature) was applied to assess the PCBA’s resilience under high heat for extended periods.
• Objective: This soak tested the long-term durability and thermal resilience of the component to ensure it would not degrade over the mission life.

4. Post-Test Analysis

Functional Verification and Data Comparison: After each thermal test, the component’s functionality was verified against baseline measurements. Any deviations were analyzed to determine if they were caused by thermal stress.

Infrared Imaging and Microscopic Inspection: Post-test inspections used infrared imaging to map heat distribution and pinpoint areas that retained residual heat. Microscopic analysis identified potential heat-induced physical defects like solder joint fractures and PCB delamination.

Component-Specific Failure Analysis: The power MOSFET and voltage regulator, which exhibited thermal drift during ramp stress testing, were subjected to failure analysis. The root cause was traced to insufficient heat sinking, which led to localized overheating.

Recommendations and Design Modifications:

• Heat Sink Redesign: Enlarged heat sinks were recommended for the voltage regulator and MOSFET, increasing heat dissipation.
• Thermal Via Placement Optimization: Additional thermal vias were added around the components with the highest thermal loads, improving heat spread.
• Component Relocation: Certain high-power components were repositioned to allow better airflow and reduce thermal coupling between sensitive components.

Key Findings and Recommendations

1. Component-Level Heat Dissipation: The voltage regulator and power MOSFET required improved heat dissipation, achieved through larger heat sinks and optimized thermal via layouts.
2. Thermal Isolation of Sensitive Components: By repositioning thermally sensitive components away from high-power components, overall heat buildup was minimized.
3. Enhanced Thermal Cycles and Soak Durability: The PCBA, after modifications, successfully passed prolonged soak tests, indicating improved long-term thermal resilience for space missions.

Conclusion

This thermal testing strategy successfully identified and mitigated potential overheating issues, ensuring the PCBA could withstand extreme temperature variations and remain operational throughout the mission. Key takeaways included the importance of accurate thermal simulation, effective test setup and monitoring, and implementing targeted design modifications to enhance thermal performance. By systematically addressing these thermal challenges, the PCBA was validated as mission-ready, providing the reliability and durability needed for space applications.

Project Leader: Tom Resh

Project duration: 3 Months

Background

A Test Management Software company, initially focused on providing solutions for vehicle testing, identified a growth opportunity to expand its scope to meet the demands of OEMs and suppliers across diverse industries. These industries, spanning automotive, aerospace, energy, and consumer electronics, required a more versatile and component-level test management system. The objective was to transform the platform from a vehicle testing-specific tool to a multi-industry, component-focused solution with pre-configured test parameters, fully integrated Verification & Validation (V&V) workflows, and alignment with industry standards.

Objectives

The primary goals for this expansion were:

1. Broaden Market Reach: Adapt the software to support multiple industries, enabling scalability and new market entries.
2. Incorporate Component-Level Testing: Shift from vehicle-level testing to offer more granular, component-specific testing capabilities.
3. Enhance V&V Capabilities: Establish a full Verification & Validation (V&V) process to streamline testing for OEMs and suppliers.
4. Implement Industry Standards and Preset Parameters: Develop an extensive library of test standards and preset test parameters that are readily configurable and appealing to OEMs across industries.

Expansion Strategy Overview

The expansion strategy comprised four key phases: Market Research and Needs Assessment, Software Customization and Development, Integration of V&V Processes, and Industry-Specific Testing Capabilities.

1. Market Research and Needs Assessment

Before initiating the software transformation, extensive market research was conducted to understand the needs of different industries and stakeholders.

• Industry Requirements Analysis: Engaged with OEMs and suppliers in aerospace, consumer electronics, energy, and medical devices to identify unique testing requirements, certification processes, and pain points.
• Component Testing Needs: Identified that suppliers increasingly needed component-level validation, especially for critical parts like batteries, electronics, sensors, and structural components.
• V&V Process Mapping: Consulted with Quality Assurance (QA) teams to map out typical V&V workflows, pinpointing stages where test management software could enhance process efficiency and compliance with regulations.
• Standards Alignment: Studied industry standards (e.g., MIL-STD, ISO 26262 for functional safety, UL standards) to create a standards library with preset test parameters.

2. Software Customization and Development

To address the requirements from different industries and enable component-level testing, the software’s architecture and user interface were modified extensively.

• Modular Architecture: Built a modular system, allowing users to select testing modules relevant to their industry (e.g., thermal testing, mechanical shock testing, electrical testing).
• Configurable Test Templates: Created configurable templates with preset parameters that align with major standards. For example, testing profiles for battery packs in automotive applications and vibration testing protocols for aerospace components.
• Component Traceability and Test History: Enhanced traceability features to manage test histories for specific components, allowing suppliers to track test results, V&V history, and compliance with OEM standards.
• Data Analysis and Reporting: Developed industry-specific reporting templates, allowing users to generate reports that meet regulatory documentation requirements and OEM reporting standards.

3. Integration of Verification & Validation (V&V) Processes

A robust V&V framework was embedded within the software to streamline testing processes, improve compliance, and ensure consistency across different stages of testing.

• V&V Process Workflow Integration: Introduced workflows aligned with typical V&V processes, including test case definition, parameter configuration, and validation stages.
• Risk Assessment and Functional Safety: Integrated risk assessment tools that aligned with ISO 26262 and other safety standards, enabling users to define risk parameters, assign safety levels, and validate critical components.
• Requirement Traceability Matrix (RTM): Implemented RTM functionality to link each test case with specific requirements, ensuring each testing stage fulfills the intended V&V criteria.
• Automated Test Validation: Provided automatic validation of test parameters based on preset thresholds, minimizing human error and speeding up the test approval process.

4. Industry-Specific Testing Capabilities

The software’s focus on industry-specific preset parameters and test protocols enabled users to perform standardized testing that met the needs of different OEMs and suppliers.

• Automotive and Aerospace Modules: Created industry-tailored modules with predefined test cases, such as thermal and shock testing for battery packs in automotive and environmental stress screening (ESS) for aerospace applications.
• Battery and Electronics Testing Parameters: Developed specific configurations for electronics testing, including Electrostatic Discharge (ESD), electromagnetic compatibility (EMC), and specific charge/discharge cycle profiles for lithium-ion battery packs.
• Flexible Standards Library: Built a standards library with preset templates for various industries, allowing users to configure tests aligned with regulatory standards (e.g., UL, IEC, and MIL standards).
• Lifecycle Management for Long-Term Testing: Added features to manage lifecycle testing and aging tests, critical for industries where components undergo extensive durability testing (e.g., aging tests for energy storage systems).

Implementation and Results

The software’s new capabilities were rolled out in phases, with a pilot program conducted in collaboration with OEMs and suppliers across multiple industries.

1. Broadened Market Reach and Adoption: OEMs and suppliers from aerospace, automotive, and electronics sectors adopted the software, benefiting from the pre-configured testing parameters and standards. Market reach grew by 35% within the first year of expansion.
2. Enhanced V&V Process Efficiency: By integrating the V&V process within the software, clients reported a 25% reduction in test cycle times and a 40% reduction in time spent on compliance reporting, significantly accelerating product development cycles.
3. Improved Component Testing Precision: The software’s component-level traceability and industry-specific testing templates led to improved accuracy and reliability in testing, reducing component failure rates by 20% for pilot clients.
4. Positive Feedback on Standards Library: Users appreciated the built-in standards library and preset test parameters, which saved time and reduced errors. It was noted that new test configurations were completed 30% faster due to these pre-configured templates.

Conclusion

Expanding the Test Management Software’s capabilities from vehicle testing to multi-industry, component-level testing proved to be a valuable strategic shift. By incorporating a comprehensive V&V process, preset parameters, and a robust standards library, the software enabled OEMs and suppliers to perform accurate, compliant, and efficient testing across a range of industries.

The success of this expansion demonstrates that focusing on industry-specific requirements and integrated V&V processes can enhance product quality and streamline testing workflows, making the software a versatile, indispensable tool for testing needs across sectors.

Project Leader: Tom Resh

Project duration: 12 months

Background

In the highly competitive and regulated space industry, a startup launch vehicle company sought to establish itself by developing a reliable and cost-effective launch vehicle. To ensure the vehicle's readiness for spaceflight, the company needed a rigorous qualification and testing plan to validate each subsystem and the entire vehicle’s performance, reliability, and safety. This case study details the approach used to design and implement a comprehensive qualification and testing plan to meet the company’s goals, industry standards, and regulatory requirements.

Objectives

The qualification and testing plan aimed to achieve the following:

1. Ensure Component and System Reliability: Validate the performance and durability of critical components and subsystems in harsh launch and space environments.
2. Meet Industry Standards and Regulatory Compliance: Align the testing approach with aerospace standards such as MIL-STD, NASA’s General Environmental Verification Standard (GEVS), and other relevant specifications.
3. Mitigate Development Risks: Identify and mitigate potential failure points through iterative testing to reduce risk during the actual launch.
4. Optimize Cost and Schedule Efficiency: Design a testing process that balances thoroughness with the company’s limited resources and accelerated timeline.

Strategy Overview

The qualification and testing strategy was structured into four main phases: Requirements Definition and Planning, Component Qualification, Subsystem and Full-System Testing, and Pre-Launch Validation.

1. Requirements Definition and Planning

In collaboration with engineering, quality assurance, and regulatory teams, the first phase involved creating a detailed set of requirements and developing a tailored testing plan.

• Requirements Development: The engineering team defined critical performance requirements based on mission objectives, including payload capacity, propulsion reliability, thermal resistance, and vibration tolerance.
• Standards Alignment: Relevant aerospace standards and regulatory requirements were mapped, including MIL-STD-1540 (Environmental Test Methods and Engineering Guidelines), NASA’s GEVS for environmental verification, and ASTM standards for material selection.
• Risk-Based Prioritization: A risk assessment identified high-priority systems and components, such as the propulsion system, avionics, and structural components, to focus the qualification and testing effort where potential failure would pose the greatest risk.
• Test Plan Development: A detailed qualification test plan was created, outlining test types, conditions, criteria for success, and required resources. This plan covered component, subsystem, and full-system tests and included contingencies for unexpected outcomes.

2. Component Qualification

To ensure reliability at the most granular level, individual components were tested under conditions simulating the launch environment.

• Thermal Cycling and Vacuum Testing: Components, particularly those exposed to the external environment (e.g., engine components, structural brackets), were subjected to extreme thermal cycling and vacuum conditions to simulate rapid temperature changes and the vacuum of space.
• Vibration and Shock Testing: Using electrodynamic shakers, key components such as avionics and the flight computer underwent vibration testing based on expected launch profiles. Shock testing simulated potential jarring forces from staging and separation events.
• Material Properties Testing: Testing was conducted on materials used in high-stress parts of the vehicle, including tensile, shear, and fatigue tests on alloys and composites to ensure structural integrity.
• Radiation and EMC Testing: For electronic components, radiation exposure testing validated performance under ionizing radiation expected in space. Additionally, electromagnetic compatibility (EMC) tests ensured that avionics and other electronic components would not interfere with each other.

3. Subsystem and Full-System Testing

Once components were qualified, the team advanced to subsystem and full-vehicle tests to verify overall system interactions and functionality under real-world conditions.

• Subsystem Testing
• Propulsion System Testing: Static fire tests were conducted to validate engine performance, thrust levels, fuel efficiency, and structural integrity of the propulsion system. Cold flow tests validated fuel and oxidizer flow without ignition, confirming flow rate and valve function.
• Avionics Testing: Flight simulation tests for the avionics system validated communication, guidance, and navigation functions. The software was subjected to Hardware-in-the-Loop (HIL) simulations, where the flight computer was connected to sensors and actuators to simulate in-flight conditions.
• Structural Load Testing: Load tests were applied to the launch vehicle’s structure to verify that it could withstand forces experienced during launch, ascent, and staging. Tests included static loads, dynamic loads, and buckling tests.
• Thermal Vacuum Testing: Key subsystems were tested in a thermal vacuum chamber to simulate the conditions of space. Components were operated while subjected to extreme heat and cold in a vacuum to ensure functionality and resilience under those conditions.
• Full-System Testing
• Integrated Systems Testing: All subsystems were integrated, and a full-vehicle systems test was conducted to validate that all parts worked harmoniously. Systems were powered on, and simulated launch conditions tested their compatibility.
• Vibration Testing for Full System: The complete launch vehicle underwent vibration testing to verify that the integration of all subsystems maintained stability and performance under launch conditions.
• Dry Run Testing: The vehicle was assembled and fueled in a dry run test to check fuel loading/unloading procedures, valve integrity, and safety protocols in a controlled environment.

4. Pre-Launch Validation

The final testing phase was designed to confirm vehicle readiness before the launch campaign.

• Simulated Flight Test (Flight-Like Simulation): The vehicle and all systems were put through simulated flight sequences in a controlled environment to verify the launch profile, staging events, and payload deployment operations. This simulated test provided a last check for system performance, identifying potential issues before the launch.
• Launch Rehearsals and Countdown Procedures: Dry rehearsals of the launch sequence involved the entire team to practice procedures, perform final checks, and troubleshoot potential launch-day issues.
• Final Quality Review and Sign-Off: A final quality review was conducted, involving key stakeholders who reviewed all test data, confirmed the qualification of components and systems, and signed off on the vehicle’s readiness for launch.

Key Findings and Lessons Learned

1. Identified Propulsion System Weakness: During static fire tests, the propulsion system showed minor instability under peak thrust, which led to a redesign of the fuel injectors. This adjustment improved fuel efficiency and stabilized thrust levels.
2. Material Improvements for Thermal Resilience: Thermal cycling tests revealed that certain alloys in high-heat regions (near the engine) were prone to thermal expansion stress, leading the team to replace them with more heat-resistant alloys.
3. Enhanced Avionics Performance: EMC testing exposed a potential for interference between the guidance system and communication modules. Shielding modifications were added to prevent signal interference.
4. Risk Reduction from Dry Run Testing: Fuel loading and valve functionality were verified through dry run testing, preventing fuel leakage that could have led to potential safety risks.
5. Procedural Improvements: The countdown rehearsals identified several points of potential human error in the launch process, leading to streamlined procedures that improved team coordination and confidence on launch day.

Conclusion

By developing a structured and comprehensive qualification and testing plan, the startup launch vehicle company effectively minimized development risks and prepared its vehicle for a reliable and safe launch. The rigorous testing program not only addressed initial design weaknesses but also validated each component and subsystem’s performance under real-world conditions, ensuring full system reliability.

The results from this case study demonstrate that a well-defined qualification and testing plan, tailored to the specific challenges of a startup, is essential for meeting aerospace standards, enhancing system robustness, and positioning the company for a successful and competitive entry into the launch vehicle market.

Project Leader: Tom Resh

Project duration: 6 Months