Challenge and Response for Corner-Case Robustness Improvement

System robustness in corner-case use can be difficult to model and improve for complex industrial system applications. We, the authors, hypothesized that an industrial metal cutting system could be methodically exposed to challenging test case input factors while closely monitoring system outputs and the normalized occurrence rate of events that may be disruptive to the end user. This empirical study of system inputs and outputs with data reduction capabilities that enabled sifting through large datasets for disruptive occurrences enabled both better targeting of improvement and subsequent verification of design improvement effectiveness, especially as relates to more stressful corner-case use conditions for complex systems. Exposing our XPR system to challenging use profiles outside of normal operating parameters exposed improvement opportunities and demonstrated the effectiveness of a challenge and response protocol approach for system improvement. Three levels of organizational communication and reporting were shown effective to promote effective mitigations, monitor progress, and maintain initiative support. The authors submit that the challenge and response test method of methodically imposing concurrent stressful inputs within a data capture infrastructure to capture detailed system response data has value for complex system corner-case behavior improvement. We submit that challenge and response work in design organizations may be aided/facilitated by securing the following checklist of items: 1. Clear understanding of corner-case disruptive event descriptors/symptoms. 2. Study of field service calls. 3. Study of field returns. 4. Customer complaint tallies for corner-case end users. 5. Management support to disposition reliability engineering and business design team resource for multiple challenge and response experimental block efforts and mitigation efforts. 6. Subject matter expert judgement and field evidences that support a set of definable key factors to vary at 2+ levels. 7. Subject matter expert judgement and field evidences supporting factor setting levels: normal use and corner-case use. 8. Test environment capable to achieve bold test factor challenge settings. 9. Data system able to collect environmental context variables, test lab inputs and system commanding inputs, internode bus communication monitoring and diagnostic code monitoring and outputs, and relevant human touch events to the systems under test. 10. Data reduction/analysis/reporting resources capable to provide meaningful/effective information at multiple detail levels for key audiences of the challenge and response work.