Aerospace and Electronic Systems Magazine April 2017 - 2
In This Issue - Technically
AIRPLANE FLIGHT SAFETY USING ERROR-TOLERANT DATA STREAM PROCESSING
For airplane flight safety, there is a need for detecting and resolving data errors that could come from faulty
sensor measurements, inaccurate data processing, or poor information transmission. Dynamic Data-Driven
Applications Systems (DDDAS) use dynamic information to update a system's model in order to more accurately predict system conditions, thereby enabling better detection and recovery from data errors. We present
a DDDAS-based approach to streaming data error that embodies in a new declarative ProgrammIng Language
for spatiO-Temporal data Streaming applications (PILOTS). We illustrate the use of PILOTS in analyzing
sensor readings that ultimately caused two commercial aviation accidents: (1) Air France Flight 447 (AF447),
and (2) Tuninter Flight 1153 (TU1153). Results demonstrate the ability to diagnose sensor measurements for
in-flight operations with the potential to increase aviation safety.
ELECTROMECHANICAL ACTUATOR FAN FAILURE ANALYSIS AND SAFETY-CRITICAL DESIGN
Recently there has been increasing research interest on aircraft electromechanical actuator (EMA) safety. EMA
failure can cause catastrophic failure in aircraft. This study compare three approaches to the prevention of
EMA overheating: a cooling fan motor with dual-winding, a cooling fan with dual-bearing, and a dual-fan
system to improve the mean time to failure. A seven-blade and five-blade dual-fan design is proposed. After
summarizing the possible causes of failure and failure modes of BLDC fans by focusing on each failure mechanism, the life expectancy of fan ball bearings based on a major failure mechanism of lubricant deterioration
was calculated and compared to the literature. Finally, after discussing the advantages and disadvantages of
the three fault-tolerant cases, the dual-rotor counter rotating fan construction is determined to be the best way
to improve fan reliability.
SUPERVISED LEARNING ALGORITHMS FOR SPACECRAFT ATTITUDE DETERMINATION AND CONTROL
SYSTEM HEALTH MONITORING
The need for semi-autonomous or autonomous operations, communication delay, short contact periods as well
as the need for survival in harsh environments poses unique challenges to space systems health management.
In this article we describe the results of applying three supervised learning anomaly detection algorithms to
the historical telemetry acquired from attitude determination and control subsystem (ADCS) of spacecraft. All
algorithms are predominantly applied to the ADCS telemetry acquired under different operation conditions
(nominal and off-nominal status) of an actual remote sensing spacecraft. Subsequently, the models are built and
validated under abovementioned conditions and the results show that they successfully differentiate between
the different operations conditions and a critical compression between the analysis results is presented.
AESS HISTORICAL INTERVIEW: CONVERSATION WITH PAUL ROSEN
In this fifth historical interview, a fascinating conversation with Paul Rosen by Riccardo Lanari, both valued
members of the Institute of Electrical and Electronics Engineers (IEEE) Aerospace and Electronic Systems Society (AESS), AESS offers our members insight into the people behind the many great contributions that grace
our field. While these interviews document historical events, they are also intended to give readers insights
into the events and critical decisions that shaped the research, technical accomplishments, and career of our
society's most legendary contributors.
INTEGRATION OF REED-SOLOMON CODES TO LICKLIDER TRANSMISSION PROTOCOL (LTP) FOR SPACE DTN
As Delay/disruption tolerant networking (DTN) primary data transport protocol for space networks, Licklider
transmission protocol (LTP) has been developed to adopt an automatic repeat request (ARQ)-based retransmission scheme that operates on multiple concurrent transmissions for reliable data delivery. In this article,
we propose a new "local data-link layer" protocol to space DTN protocol stack, simply named RS-LTP that
integrates RS erasure coding to LTP for more efficient data delivery in space communication networks. Data
transfer experiments are conducted using an emulated space communication testbed infrastructure to evaluate
the performance improvement of RS-LTP over LTP (without RS coding implemented).
IEEE A&E SYSTEMS MAGAZINE