Search NASASearch

Engineering topics

Siemers, P.

Publications and source records attributed to Siemers, P..

Technology and test

The chairman of the Technology Applications in Space Working Group summarizes the technology issues for each of the disciplines in Tethered Satellite Systems. The disciplines are Tether Materials and Configurations, Tether System Dynamic Simulation Capability, Tether System Instrumentation, TAS Program Related Science Instrumentation, Atmospheric/Aerothermodynamic tethered system research, and TAS Discipline Program Accomplishment. To enable these tether applications, design and development programs have been recommended and are presently underway relative to the demonstration of the hollow cathode concept which is an enabling electrodynamic tether mission technology.

Siemers, P.

Technology and Test

The status of tether-related technology is discussed together with the program that should be initiated to develop the technology required by the tethered satellite system. Successful tethering during the Gemini program is mentioned. Technology areas which appear to have application to tethered systems are identified, including electrodynamics, atmospherics, and aerothermodynamics.

Siemers, P.

Summary presentation of the technology and test panel

Tether related technology issues were investigated along with potential applications. Several of the applications do not derive necessarily from nor are they related to a technology issue. Tether designs must concern itself with length requirements (whether the tether is to be flexible or stiff) and what the environmental impact is on the particular material that is proposed for the tether. As far as tether manufacturing techniques, a lot of technology related work is required to develop cost effective manfacturing capabilities for the future tether. There are techniques that are used on the ground now. However, after some of the proposed applications are determined to be feasible, it may be that the best way to manufacture the tether is to pretend the satellite is a spider and allow it to spin its own web in space. The technology required to developed tapered tethers was considered. Definition of the taper, where the center of that taper should be, and the taper's relation to the end masses are all of concern.

Siemers, P.

Report of the Technology and Test Panel

The state of technology relative to the Tethered Satellite System (TSS) was reviewed. The technology areas which could benefit from the TSS were defined. To support TSS design studies it is necessary to develop tether dynamic model computer codes for definition of mission and tether requirements. Present major codes are very elaborate, expensive to run, and not very user friendly. An additional technology concern was related to the manufacturing of tethers. The development of complex tethers (nonconducting-taper/double taper long 100 km, conducting-embedded conduction, fiber optics, and superconducting) and their applications to space stations requires the development of manufacturing capabilities for both Earth-based as well as space-based systems.

Siemers, P.