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Norman, R. M.

Publications and source records attributed to Norman, R. M..

8 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2007

Synthetic Vision Enhanced Surface Operations With Head-Worn Display for Commercial Aircraft

Experiments and flight tests have shown that airport surface operations can be enhanced by using synthetic vision and associated technologies, employed on a Head-Up Display (HUD) and head-down display electronic moving maps (EMM). Although HUD applications have shown the greatest potential operational improvements, the research noted that two major limitations during ground operations were its monochrome form and limited, fixed field-of-regard. A potential solution to these limitations may be the application of advanced Head Worn Displays (HWDs) particularly during low-visibility operations wherein surface movement is substantially limited because of the impaired vision of pilots and air traffic controllers. The paper describes the results of ground simulation experiments conducted at the NASA Langley Research Center. The results of the experiments showed that the fully integrated HWD concept provided significantly improved path performance compared to using paper charts alone. When comparing the HWD and HUD concepts, there were no statistically-significant differences in path performance or subjective ratings of situation awareness and workload. Implications and directions for future research are described.

Arthur, Jarvis J., III↗
NASA NTRS1996

Guidance and Control Design for High-Speed Rollout and Turnoff (ROTO)

A ROTO architecture, braking and steering control law and display designs for a research high speed Rollout and Turnoff (ROTO) system applicable to transport class aircraft are described herein. Minimum surface friction and FMS database requirements are also documented. The control law designs were developed with the aid of a non-real time simulation program incorporating airframe and gear dynamics as well as steering and braking guidance algorithms. An attainable objective of this ROTO system, as seen from the results of this study, is to assure that the studied aircraft can land with runway occupancy times less then 53 seconds. Runway occupancy time is measured from the time the aircraft crosses the runway threshold until its wing tip clears the near side of the runway. Turnoff ground speeds of 70 knots onto 30 degree exits are allowed with dry and wet surface conditions. Simulation time history and statistical data are documented herein. Parameters which were treated as variables in the simulation study include aircraft touchdown weight/speed/location, aircraft CG, runway friction, sensor noise and winds. After further design and development of the ROTO control system beyond the system developed earlier, aft CG MD-11 aircraft no longer require auto-asymmetric braking (steering) and fly-by-wire nose gear steering. However, the auto ROTO nose gear hysteresis must be less than 2 degrees. The 2 sigma dispersion certified for MD-11 CATIIIB is acceptable. Using this longitudinal dispersion, three ROTO exits are recommended at 3300, 4950 and 6750 feet past the runway threshold. The 3300 foot exit is required for MD-81 class aircraft. Designs documented in this report are valid for the assumptions/models used in this simulation. It is believed that the results will apply to the general class of transport aircraft; however further effort is required to validate this assumption for the general case.

Goldthorpe, S. H.↗
NASA NTRS1978

Cooling radioisotope thermoelectric generators in the Shuttle

Radioisotope thermoelectric generators (RTG) to be used on future spacecraft and launched by the Shuttle must be cooled from the time they are installed and enclosed until the spacecraft is deployed from the Shuttle. A special Cooling Kit maintains their temperature well below critical by circulating water through the coils soldered to them and through a heat exchanger that boils water and externally discharges the resulting steam. The RTG Cooling Kit, including its support frame, if fully charged with about 64 kg of evaporation water, will increase the Shuttle launch mass by about 200 kg.

Norman, R. M.↗
NASA NTRS1976

Zero torque gear head wrench

A gear head wrench particularly suited for use in applying torque to bolts without transferring torsional stress to bolt-receiving structures is introduced. The wrench is characterized by a coupling including a socket, for connecting a bolt head with a torque multiplying gear train, provided within a housing having an annulus concentrically related to the socket and adapted to be coupled with a spacer interposed between the bolt head and the juxtaposed surface of the bolt-receiving structure for applying a balancing counter-torque to the spacer as torque is applied to the bolt head whereby the bolt-receiving structure is substantially isolated from torsional stress. As a result of the foregoing, the operator of the wrench is substantially isolated from any forces which may be imposed.

Mcdougal, A. R.↗
NASA NTRS1974

Bolt installation tool for tightening large nuts and bolts

Large bolts and nuts are accurately tightened to structures without damaging torque stresses. There are two models of bolt installation tool. One is rigidly mounted and one is hand held. Each model includes torque-multiplier unit.

Mcdougal, A. R.↗
NASA NTRS1970

Compression springs used for vibration isolation

System that employs opposed pairs of compression springs can be totally compressed to provide a ''hard mount'' during component installation and adjustment, and can be released to a free-floating condition for vibration isolation during test.

Norman, R. M.↗
NASA NTRS1969

Four-bar linkage for thermal compensation in test mounts for structures

Supporting system compensates automatically for the dimensional changes produced by contraction and expansion of structures undergoing thermal proofing on mounts. Structurally destructive forces would be exerted on a spacecraft in a simulator if this four bar linkage test mount was not used.

Norman, R. M.↗