Engineering topics
Publications and source records attributed to Levinson, S..
Magnetic transducers tunes laser by making small precise adjustments in length of laser resonant cavity. Device is simple and stable structure consisting of electromagnet pulling on spring supported magnetic plate.
Scanning scheme is more efficient than conventional scanning. Originally designed for optical radar in space vehicles, scheme may also find uses in site-surveillance security systems and in other industrial applications. It should be particularly useful when system must run on battery energy, as would be case in power outages.
Investigations were made of a configuration for a spaceborne laser radar (ladar) to meet the requirements for rendezvous and docking with a cooperative object in synchronous orbit. An analysis was completed of laser phase locking techniques, while experimental verification was made of pulse repetition frequency and resonant scanning control loops. Data measurements on a satellite mock-up were also made. The investigation supports the original contention that a rendezvous and docking ladar can be configured to offer a cost effective and reliable solution to envisioned space missions.
Incoming signal is mixed with local oscillator signal by a beam splitter inside laser cavity. Laser power can be reduced by 50 to 100 times.
The use, design, and fabrication feasibility of scanning the laser beam by swiveling the outside mirror with a ball joint swivel system is examined along with the applicability of graphite reinforced epoxy material for the construction of reflective optics. It is indicated that (1) the cost of graphite-epoxy will be more than that of many other materials due to the amount of special tooling required; (2) the weight advantage of graphite-epoxy over beryllium is minimal; the ball joint swivel system is accurate enough to perform the scanning function; and that the ball joint will result in a simpler and more cost effective scanning mechanism.
A ladar (laser radar) sensor designed around a pulsed passively Q-switched CO2 laser, capable of a efficient and rapid scans with a narrow beam over a wide field of view, is considered for surveillance and tracking applications in space. The output is a train of narrow pulses with a controllable pulse repetition rate. A resonant vibrating mirror in back of a classical Gregorian telescope, and a plane pointing mirror in front for beam steering, are used in scanning. Scan pulse sequences are described and illustrated. The 10.6 micron ladar set is under consideration as baseline sensor for various space rendezvous and docking applications.
A spaceborne laser radar (LADAR) was configured to meet the requirements for rendezvous and docking with a cooperative object in synchronous orbit. The LADAR, configurated using existing pulsed CO2 laser technology and a 1980 system technology baseline, is well suited for the envisioned space tug missions. The performance of a family of candidate LADARS was analyzed. Tradeoff studies as a function of size, weight, and power consumption were carried out for maximum ranges of 50, 100, 200, and 300 nautical miles. The investigation supports the original contention that a rendezvous and docking LADAR can be constructed to offer a cost effective and reliable solution to the envisioned space missions. In fact, the CO2 ladar system offers distinct advantages over other candidate systems.