Patents

Cellular Support Structures used for Controlled Actuation of Fluid Contact Surfaces: Patent pending, filed 16 Feb 2007

Invented by: Curt Kothera (TSi), Ben Woods (TSi), Edward Bubert (TSi), Norman Wereley (UMD), and Peter Chen (TSi)

The honeycomb structures of this invention utilize novel cell geometry to produce a structural core system that is capable of achieving broad shape and area changes, to be incorporated into morphing aerofoils and structures for the purpose of providing resistance to shear loading and maintaining structural integrity during the all stages of the conformal changes in configuration. Aerospace structures composed of these honeycombs, along with a morphing skin and actuation system, have the benefit of static shape control (such as morphing configuration) and dynamic control (such as flight augmentation). Paramount to the invention is the unique cellular orientation of the structure that permits a Poisson's ratio of zero. That is, these structures de-couple the transverse and longitudinal relationships seen in positive Poisson materials (standard honeycomb, rubber) and negative Poisson structures (auxetics). This is accomplished by arranging the re-entrant cells such that parallel rows of unit cells are fixed to and separated by rib-like members that maintain constant length while the re-entrant members deform the structure in different directions.

Fluid-Driven Artificial Muscles as Mechanisms for Controlled Actuation: Patent pending, filed 11 Aug 2006

Invented by: Curt Kothera (TSi), Ben Woods (TSi), Jayant Sirohi (UMD), Norman Wereley (UMD), and Peter Chen (TSi)

The actuation system of this invention utilizes fluid-driven artificial muscles (FAMs) to manipulate control surfaces for improved aerodynamic characteristics and stability. Bi-directional operation can be achieved for either primary or secondary control, though dual use systems can also be arranged. Featuring three primary components, the system includes fluid-driven artificial muscles, such as the McKibben actuator, a load transfer mechanism, and a control surface. Together with a control system and safety device, the invention provides a highly adaptable, compliant, and lightweight actuation technology that is particularly attractive to air and sea vehicles, both fixed wing and rotary, large-scale and unmanned-scale, and with extensions to morphing configurations.

Adaptive Energy Absorption System for a Vehicle Seat: Patents Pending Three utility patent applications filed with priority date of May 31, 2006

Invented by: Gregory Hiemenz (TSi), Peter Chen (TSi), Gang Wang (TSi), Norman Wereley (UMD), Peter Hu (UMD), & Young-Tai Choi (UMD)

The vehicle seat suspension system of this invention uses variable profile energy absorbers (VPEAs), such as a magnetorheological (MR), electrorheological (ER), or active valve fluid dampers, to mitigate injurious loads to the occupant during a vertical shock event. Such events may include crash or harsh landings of aircraft, ballistic or underwater shock events, the repetitive shock due to traveling high speeds over a waves, etc. In this invention, the energy absorbing capabilities of the VPEAs are optimally adjusted real-time by a feedback control system to maintain occupant loads below injurious levels. This system may adapt its energy absorption capability to prevent injury for varying input levels - optimally adjusting the load-stroke profile of the VPEA to fully utilize the entire suspension stroke and minimize the load transmitted to the occupant. Furthermore, this system may adapt itself to occupant weight - providing equal protection for all expected occupants. This invention may also have a secondary goal of providing increased comfort and reduced fatigue by isolating the occupant from lower amplitude vibrations during normal operation. Also included in this invention are VPEA configurations which make such a dual-goal system realistically achievable as well as system configurations combining VPEAs with conventional energy absorbers.

Gun Muzzle Control System Using Barrel Mounted Actuator Assembly

Patent Number: 5,631,437

Invented by: Christopher LaVigna (TSi), Gilmer Blankenship (TSi) and Harry Kwatny (TSi)

Device for precision aim control of a gun barrel muzzle of a turreted gun system for improved projectile accuracy. The invention includes a compact actuator assembly mounted to a flexible gun barrel that act in combination with elevation and azimuth actuators located in the gun's turret. The device also includes a muzzle sensory feedback subsystem for continuous sensing of the gun muzzle's displacement, azimuth and elevation angles as the gun is fired. The barrel mounted actuator assembly along with the muzzle sensory feedback subsystem significantly improves the muzzle's aim performance.

Optical Fiber Vibration Modal Filter for Flexible Structures Produced by the Photorefractive Effect

US Patent Number: 5,572, 609

Invented by: Yaowen Li (UMD) and James Sirkis (UMD)
(University of Maryland Patent : Exclusive license to TSi)

Method and apparatus for fabricating optical fiber vibration modal filtering sensors. Such filters are used in vibration control of engineered structures, especially flexible structures. In particular, the optical fiber sensor is made by a functionally weighted exposure of an optical fiber to ultra-violet laser source thereby modifying the refractive index of the optical fiber core resulting in a vibrational modal filtering sensor using a single mode interferometric detection scheme.

Fiber optic sensor for spatially separated elements in a system

US Patent Number: 5,825,948

Invented by: Christopher LaVigna (TSi), Yaowen Li (UMD), and James Sirkis (UMD) (Exclusive license to TSi of University of MD Rights)

A fiber optic sensor employs a tapered fiber optic integrating strain sensor in a tapered gun barrel to measure the gun barrel bending response. The fiber optic sensor employs a single-mode optical fiber, a light source supplying light to the single-mode fiber and at least one tapered dual-mode optical fiber secured to the barrel in a longitudinal direction. The single-mode fiber is spliced to with an end of a proximal one of the dual-mode fibers for carrying the light signal. A partial reflector is inserted between the dual-mode fibers to partially reflect and partially transmit light. A reflector is coupled to a distal end the dual-mode fiber, at the open end of the muzzle of the gun, to reflect the transmitted light. A coupler couples the single-mode fiber to the proximal dual-mode fiber. A coherent multiplexer is connected to the coupler for receiving and multiplexing the reflected light. A processor is responsive to the multiplexer for processing the multiplexed sensing information. The dual-mode fiber is tapered inversely with respect to the tapered muzzle to simplify the processing function.

Apparatus and Method for Measuring Exit Velocity of a Gun Round

US Patent Application Number: 20030156272

Foreign filings in progress

Invented by: Christopher LaVigna (TSi), Sheldon Cytron (uS Army) , Justin Bowlus (TSI), Gaurav Bajpai (TSi), and Shiping Chen (UMD) (Exclusive license to TSi of University of MD Rights)