A practical characterization of a NASA SpaceCube application through fault emulation and laser testing

Historically, space-based processing systems have lagged behind their terrestrial counterparts by several processor generations due, in part, to the cost and complexity of implementing radiation-hardened processor designs. Efforts such as NASA's SpaceCube seek to change this paradigm, using higher performance commercial hardware wherever possible. This has the potential to revolutionize onboard data processing, but it cannot happen unless the soft error reliability can be characterized and deemed sufficient. A variety of fault injection techniques are used to evaluate system reliability, most commonly fault emulation, fault simulation, laser testing, and particle beam testing. Combining multiple techniques is more complex and less common. In this study we characterize a real-world application that leverages a radiation-hardening by software (RHBSW) solution for the SpaceCube platform, using two fault injection strategies: laser testing and fault emulation. We describe several valuable lessons learned, and show how both validation techniques can be combined to greater effect.