Evaluation of the Space Shuttle Cockpit Avionics Upgrade (CAU) Displays
In 1999, NASA Johnson Space Center (JSC) initiated a Cockpit Avionics Upgrade (CAU) project to increase shuttle mission safety by improving the crew's situation awareness, reducing their workload, and improving their performance. The primary focus of the project was a complete redesign of the current cockpit displays. To determine the effectiveness of the redesigns, a human-centered evaluation was conducted in the Shuttle Mission Simulator (SMS) at NASA JSC in 2003 and 2004. Measures of crew situation awareness, workload, and nominal and off-nominal task handling performance were made in a series of simulations of off-nominal flight situations during the dynamic flight phases of ascent and entry. The redesigned display formats yielded dramatic increases in situation awareness, reductions in workload, and improvements in performance.
Integrating Planning, Execution and Diagnosis to Enable Autonomous Mission Operations
NASA’s Advanced Exploration Systems Autonomous Mission Operations (AMO) project conducted an empirical investigation of the impact of time delay on today’s mission operations, and of the effect of processes and mission support tools designed to mitigate time-delay related impacts. Mission operation scenarios were designed for NASA’s Deep Space Habitat (DSH), an analog spacecraft habitat, covering a range of activities including nominal objectives, DSH system failures, and crew medical emergencies. The scenarios were simulated at time delay values representative of Lunar (1.2-5 sec), Near Earth Object (NEO) (50 sec) and Mars (300 sec) missions. Each combination of operational scenario and time delay was tested in a Baseline configuration, designed to reflect present-day operations of the International Space Station, and a Mitigation configuration in which a variety of software tools, information displays, and crewground communications protocols were employed to assist both crews and Flight Control Team (FCT) members with the longdelay conditions. This paper describes the mitigation configuration, with specific attention on the plan and procedure execution tracking and fault detection, isolation and recovery software.
Heat Transfer Characteristic for a New Plate Metal Hydride Reactor
The property of major metal hydride reactors in the world was analyzed and a new plate metal hydride reactor was designed.An experimental facility to test the metal hydride reactor was also designed correspondingly.The effective thermal conductivity of the plate metal hydride reactor was measured by varying the initial metal hydride packing fraction,the kind of filled gas and the pressure of the filled gas,cycle numbers.The test results show that the effective thermal conductivity of the reactor,has exceeded(7.5) W/(m·K) before activation,which is increased greatly.After alloy activation,the effective thermal conductivity of the reactor has a linear change trend with the hydrogen pressure during the interval 0.1~3.5 MPa.The effective thermal conductivity of the reactor just only decreases quickly at the beginning,but becomes stable after several cycles.