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Jacoby, Rick

Publications and source records attributed to Jacoby, Rick.

Extravehicular activity self-rescue using a hand-held thruster

A study was performed in the virtual interactive environment workstation. Simulations were conducted to assess the feasibility and quantify the fuel and time requirements for a stranded crewperson to return to a space station after an accidental separation. A hand-held thruster, similar to the hand-held maneuvering unit from the Gemini program, was used for propulsion. Thirty different separation scenarios were composed of three separation rates, five initial spin rates, and an opportunity to use an attitude hold device in a repeated measures design. Statistically significant results were produced by separation velocity. Fuel, time maximum range, time to maximum range, maximum axial range, and final axial velocity increased with separation rate. A hand-held thruster is a viable alternative for accomplishing a self-rescue. Although one cannot prove a null effect, the fact that an attitude hold capability did not decrease solution time or fuel consumption is important for system designers. This fact, coupled with the success of a hand-held thruster in simulations, suggests that the added expense of more sophisticated solutions requiring a multitude of thrusters - and higher computation and power capabilities - may be unwarranted.

Brody, Adam R.↗

Man overboard - What next?

A study was performed in the Virtual Interactive Environment Workstation (VIEW) at NASA Ames Research Center. Simulations were conducted to assess the feasibility and quantify the fuel and time reguirements for a stranded crewperson to return himself to a space station after an accidental separation. A hand-held thruster, similar to the Hand-Held Maneuvering Unit from the Gemini Program was used for propulsion. Thirty different separation scenarios were composed of three separation rates, five initial spin rates, and ability to use an attitude hold mode in a repeated measures design. Statistically significant results were produced by separation velocity. Fuel, maximum range, time to maximum range, maximum axial range, and final axial velocity increased with separation rate. VIEW was determined to be a useful device for simulating accidental separations, and a hand-held thruster is a viable alternative for accomplishing a self rescue.

Brody, Adam R.↗

Simulation of extra-vehicular activity (EVA) self-rescue

Self-rescue during EVA is examined in terms of the use of a hand-held thruster that is similar to the hand-held maneuvering units HHMU developed for earlier programs. The problem of assessing velocity-increment requirements is addressed by means of examples of simulation technologies for studying EVA. The technologies evaluated include virtual reality systems such as the Virtual Interactive Environment Workstation (VIEW) and the Space Operations Simulator, and standard approaches like the air-bearing floor and the space shuttle. The VIEW is employed for a study of five trained NASA subjects that conduct a simulated return to a spacecraft with an HMMU under variable conditions. The study demonstrates the efficacy of VIEW for obtaining fuel-consumption values, and separation velocity is identified as the most significant determinant of the fuel and time requirements for a self-rescue operation.

Brody, Adam R.↗