Pelican: Radiation-Tolerant Computational Storage

Zephyr proposes to continue work on Pelican, a radiation-tolerant computation storage device. This storage device provides high-capacity solid state storage through the use of 3D-NAND technology and a custom flash-controller implementation. Pelican is designed from the ground up to mitigate the adverse effects of radiation while providing high performance with low Size, Weight, and Power (SWaP). In addition, Pelican provides onboard compute resources with both general purpose and AI-enabled processors attached to the flash memory to accelerate IO intensive workloads by co-locating them with the storage. This allows for the generation of data products on the storage device itself, reducing processing time and effectively increasing the bandwidth between Pelican and a host device. The complete storage device simplifies integration by using the industry standard form factor, PC104. The primary data interface is Non-volatile Memory Express (NVMe) protocol over a Peripheral Component Interconnect Express (PCIe) Interface, though it will be possible to customize this as needed. Storage capacity in the first version will be at least 2 TB of usable space. This is not raw capacity, but instead accounts for the redundancy and over-provisioning required to meet reliability requirements. Future versions of the product will increase the capacity to 6 TB and beyond. Sequential reads and write speeds support modern Earth observation workloads with 2,000 and 1,000 MB/s respectively. Modern spacecraft collect, store, and transmit huge amounts of data, but data storage solutions have not kept up. Older and well characterized data recorders are highly reliable, but have low capacity, low bandwidth, and require large amounts of size, weight, and power. Commercial satellites are now using commercial SSDs due to their capacity and performance. These drives are designed for consumer electronics devices and ground-based data centers but are not well adapted for use in the thermal and radiation environment in orbit. Zephyr Computing Systems’ Pelican SSD uses 3D NAND flash to provide high capacity like commercial SSDs, but replaces the controller with a custom design specifically engineered for the radiation environment of space to provide high reliability like legacy data recorders. Additionally, the design provides a Computational Engine to enable data processing and AI/ML workloads directly on NAND data. Pelican delivers reliable storage with a 10x improvement in capacity and performance with 10x less mass compared to existing systems. The principal objective of the proposed Phase 2 effort is to build and test a fully functional prototype unit that is ready for flight testing. This includes designing and building a custom PCBA in an appropriate form factor for integration with spacecraft, developing the gateware and firmware to provide complete functionality, and successfully executing a test campaign comprising functionality checks, electrical validation, and environmental qualification. This minimum viable product (MVP) is the primary objective for this effort. In addition, there are several secondary objectives that are dependent on the successful delivery of a working prototype. This includes extended testing, both on the ground and on orbit, as well as optimization of the gateware, firmware, and software design. Ground based radiation testing will help us understand radiation-induced failure modes, specific subsystems’ vulnerabilities, and provide an indication of upset frequency and lifetime in space. Space based testing will build flight heritage and validate models for radiation and thermal effects. Optimizing the gateware and firmware design will allow for taking full advantage of the existing hardware. This includes tuning the performance for various use cases, reducing overprovisioning requirements, and enabling in-drive computation capabilities.
Benefits: The improved data storage capability that Pelican will offer will benefit various NASA programs by providing high performance, highly reliable data storage and facilitating onboard data analysis with minimal size, weight, and power Examples of relevant applications include: • science missions, particularly those requiring capturing and managing large amount of data • facilitating onboard AI/ML processing. • rendezvous and proximity operations. • terrain relative navigation. Zephyr has conducted extensive discussions with potential clients and industry experts. Relevant commercial applications include: • Data storage for Earth observation constellations. • Onboard processing for synthetic aperture RADAR and hyperspectral imaging. • Payload controller - command and data handling system. • Filesystem storage for flight and payload computers.