187 results about "Rolling moment" patented technology

A method of reducing the bending moment effect of wind gust loads acting on the wing of an aircraft involves adjusting the aerodynamic configuration of the wing so as to alter the distribution of lift generated by the wing during phases of flight in which critical wind gusts are expected to occur. Particularly, during climb and descent phases of flight below cruise altitude, the lift generated by outboard portions of the wings is reduced while the lift generated by inboard portions of the wings is increased. Thereby, the 1 g basis load acting on the outboard portions of the wings is reduced, and consequently the total load applied to the outboard portions of the wings, resulting from the 1 g basis load plus the additional wind gust load, is correspondingly reduced. This leads to a reduction of the bending moments effective on the wings, and of any rolling moment effective on the aircraft. The required adjustment of the lift distribution is preferably achieved by deflecting the ailerons of both wings symmetrically upward and/or deflecting the flaps of both wings symmetrically downward during climb and descent. The adjustment of the wing configuration is carried out dependent only on flight parameters such as the altitude, speed and gross weight, and does not require rapid sensing of the occurrence of a wind gust and rapid actuation of control surfaces to try to instantaneously counteract a wind gust as it occurs.

The invention relates to a mechanism to control the pitch and/or roll and/or center of gravity of a vehicle. The first embodiment is a track-based mass transfer system in which pathways are positioned along or radially terminate at a central horizontal plane of the vehicle to move one or more mass transfer devices to a desired location to control the pitch and/or roll and/or center of gravity of the vehicle. A second embodiment is a fluid mass distribution system in which one or more conduits selectively distribute a fluid to one or more tanks positioned near a central horizontal plane of the vehicle to control the pitch and/or roll and/or center of gravity of the vehicle.

A method of controlling wing position and velocity for a flapping wing air vehicle provides six-degrees-of-freedom movement for the aircraft through a split-cycle constant-period frequency modulation with wing bias method that generates time-varying upstroke and downstroke wing position commands for wing planforms to produce nonharmonic wing flapping trajectories that generate non-zero, cycle averaged wing drag and alter the location of the cycle-averaged center of pressure of the wings relative to the center of gravity of the aircraft to cause horizontal translation forces, rolling moments and pitching moments of the aircraft.

A rollover sensing system (12) that may be used in the determination of when to deploy restraints in the vehicle. The rollover sensing system (12) may include lateral acceleration sensors (32), a roll rate sensor (18), and a roll angle detector (20). A control circuit (16) determines a roll moment of inertia as a function of the lateral acceleration, a trip point length as a function of the lateral acceleration and a trip point angle as a function of the lateral acceleration. The control circuit (16) determines a rollover threshold in response to the roll rate signal, the roll angle signal, the trip point length, the roll moment of inertia, and the trip point length. The control circuit generates a control signal for the deployment circuit in response to the rollover threshold.

The invention provides a balance system with an inhibition structure and comprises a balance, a small inner-ring shaft, a first bearing, a second bearing, a sleeve, a closing ring and a bearing housing. The front end of the small inner-ring shaft is connected with and matches with the back cone of the balance through a cone; the first bearing and the second bearing closely match with the small inner-ring shaft; the sleeve is arranged on the small inner-ring shaft between the first bearing and the second bearing; the first bearing is fixed by the closing ring and the second bearing is fixed by the small inner-ring shaft; the bearing housing closely matches with the first bearing and the second bearing. The inhibition structure of the invention results in that the normal force, the pitching moment, the lateral force and the yawing moment endured by the model in the test can be absorbed by the bearing and the bearing housing in the inhibition structure, therefore, the measurement of the balance cannot be affected and the rolling moment can be transmitted to the balance basically without any loss; thereby, the invention can effectively reduce the interfere of the rolling moment component due to other components of the balance and improve the measuring precision of the rolling moment.

The invention discloses a high-precision device for measuring a rolling moment based on a mechanical bearing support, which is lower in researching and testing costs, higher in precision as comparison with the conversional high-precision rolling moment strain gauge balance and capable of meeting the requirement for small rolling moment wind channel measurement of a wind channel model in various attack angle states. The high-precision device comprises a simple component rolling moment balance (200) and a mechanical bearing support (100), wherein the mechanical bearing support (100) comprises a shell assembly (101), a rotary inner sleeve assembly (102) and a central shaft assembly (103); the rotary inner sleeve assembly (102) is arranged inside the shell assembly (101) by using an outer ring bearing and arranged on the central shaft assembly (103) by using an inner ring bearing; the front end of the shell assembly (101) is fixedly provided with a measured wind channel model (300); and the central shaft assembly (103) is provided with the simple component rolling moment balance (200) and fixed on a model supporting rod (400).

The invention discloses a calibration device and a calibration method for a rod type balance. The device comprises a calibration support, a calibration lower bracket, a calibration upper bracket, therod type balance, a loading sleeve, loading rings, an axial force loading disc, and pallets. The calibration support is connected to an optical bench. The calibration lower bracket is connected to thecalibration support. The calibration upper bracket is positioned by the calibration lower bracket by a round pin, and is tightened by a screw. The straight section such as the tail of the rod type balance is matched with a circular hole of the calibration upper bracket. The rod type balance is circumferentially positioned by a square key I, and is tightened by a nut I. The loading sleeve is matched with the taper of the front end of the rod type balance, and adopts a square key II to perform circumferential positioning on the rod type balance. The rod type balance is tightened by a nut II. The loading rings used in pairs are fixed to one whole ring by bolts, and are matched with the keys on the loading sleeve for circumferential positioning. The axial force loading disc is fixed on the loading sleeve, and can place weights to load an axial force in the vertical state of the balance. The pallets are fixed on the loading rings by detachable hinges, and can place the weights to load a normal force/pitching moment, a lateral force/yaw moment, and a rolling moment.

A rotor system (12) for a helicopter (10) includes a rotating shaft (82). A gimbaled hub assembly (56) is coupled to the rotating shaft (82). Rotating blades (24) and non-rotating blades (33) are coupled to the gimbaled hub assembly (56). The non-rotating blades (33) provide lift for the helicopter (10) in forward flight unloading the rotating blades. The rotating and non-rotating blades (24, 33) provide equal and opposite rolling moments for lift offset operation.

A suspension system for a vehicle, including: a stabilizer apparatus configured to change a stabilizer force by an operation of an actuator; a pair of absorbers of a hydraulic type each configured to change a damping coefficient thereof: a control device which includes (a) a stabilizer-force control portion configured to control the stabilizer force in accordance with roll moment acting on a body of the vehicle and (b) a damping-coefficient control portion configured to control the damping coefficient of each of the absorbers, wherein the damping-coefficient control portion is configured to execute a damping-coefficient reduction control for reducing the damping coefficient of each of the absorbers when a prescribed condition is satisfied and wherein the stabilizer-force control portion is configured to increase the stabilizer force in an instance where the damping-coefficient reduction control is under execution, as compared with an instance where the damping-coefficient reduction control is not under execution.

The invention discloses a small-range high lift-drag ratio force-measuring balance applied to a low-density wind tunnel. The small-range high lift-drag ratio force-measuring balance comprises a main balance body; and a model connection end, a first combined measuring component, an axial force measuring component, a rolling moment measuring component, a second combined measuring component and a fulcrum bar are arranged at the main balance body successively. According to the invention, the axial force measuring component and the rolling moment measuring component are arranged in the middle of the balance measuring component and the combined measuring components are arranged at the two ends symmetrically so as to reduce the interference on the axial component and rolling torque component by the large normal and pitching torque loads, thereby measuring the rest of four components except the axial force and the rolling torque. On the basis of the designed load and appearance dimension of the small-range high lift-drag ratio force-measuring balance, the force measuring testing requirement of the low-density wind tunnel with the large lift force and complex appearance model is met and thetesting capacity of the low-density wind tunnel is improved effectively. Meanwhile, the anti-interference capability of the axial force measurement precision is enhanced; and the rolling torque sensitivity and measurement accuracy are improved.

The invention discloses a six-component optical fiber aerodynamic force measuring balance and an outputting signal combining method. The six-component optical fiber aerodynamic force measuring balancecomprises a model connecting end, a normal force/pitch moment/lateral force/yawing moment/rolling moment combined measuring element, an axial force measuring element, a strut and a support connectingend. Holes and grooves which are used for laying of optical fibers guided out by optical fiber strain gauges on the various measuring elements are formed in a structural body of the optical fiber aerodynamic force measuring balance, the problem that laying of lead-out lines of optical fiber strain gauges, particularly laying of lead-out lines of optical fiber strain gauges of axial force elements, is difficult can be solved effectively, requirements of six-component aerodynamic load measurement of an aerodynamic force test of a wind tunnel model of an aerospace craft are met, reasonable combination of output signals of the optical fiber strain gauges is adopted, interference among the various components of the optical fiber aerodynamic force measuring balance can be relieved or eliminatedeffectively, and six components of the optical fiber aerodynamic force measuring balance are measured independently.

A system and method protects against rollover in a vehicle by employing an array of linear acceleration sensors. A control module includes, among other things, a model of the vehicle dynamics and a model of the array of sensors. A state vector is estimated based on the detected accelerations, the model of the vehicle dynamics and the model of the sensors. A control signal is generated based on the state vector, and the roll moment of the vehicle is reduced based on the control signal.

Monorail vehicle that travels on a non-featured rail with substantial profile variation and controls roll attitude, lateral location, and loading through judicious placement of the vehicle's center of gravity without using springs or suspensions. The vehicle has a bogie for engaging the non-featured rail so the center of gravity has a lateral offset r₁ from the rail centerline to produce a roll moment N_r determined by vehicle's mass and value of r₁. The center of gravity also has a vertical offset r₂. The bogie uses first and second assemblies for engaging the rail to produce a pair of surface normal reaction forces to thus control roll attitude and loading by the placement of the center of gravity, thereby enabling accurate alignment of the monorail vehicle.

The invention provides a small asymmetrical reentry body aerodynamic force measuring device supported by an air bearing.The device achieves measuring through an inner and outer balance nest combination measuring method, a center ventilation rod type six-component balance assembly is selected in an inner balance, and a hollow spoke type structure is adopted in an outer balance, and the inner balance and the outer balance are connected through the air bearing with tiny rolling frictional damping.The small asymmetrical reentry body aerodynamic force measuring device comprises a tail fulcrum bar, an air bearing supporting device, a model back section and a model front section.The tail fulcrum bar is fixedly connected with the air bearing supporting device and a model mechanism.The air bearing supporting device is connected with the model back section, and the model back section and the model front section are connected through threads.The aerodynamic force measuring device is simple in structure, small in size and high in integral rigidity.Different measurement components are distributed on the inner balance and the outer balance according to measurement load characters and balance structure constraint conditions, the aerodynamic force measuring device is suitable for hypersonic speed wind tunnel tests of small asymmetrical reentry body aerodynamic force measuring and especially can control measurement interference of other large load components on small rolling moment, and the measuring precision is improved.

In rotorcraft having rotors on multiple masts, a controller causes opposing roll mast moments to be applied to the different rotors. In preferred embodiments, the opposing roll moment is the result of increasing the lift on the advancing blade and reducing the lift on the retreating blade on the second rotor. This can be accomplished in any suitable manner, such as by applying differential cyclic roll control to the two rotors by tilting the two Swashplates of the two rotors or by using Individual Blade Control (IBC).

The invention discloses a flight parameter measurement system for a small-size bypass aircraft, which can achieve the purpose of enhancing the measurement convenience and the accuracy of measured data. The flight parameter measurement system for the small-size bypass aircraft comprises a test platform seat, a linear guide rail, a torque sensor, a universal joint coupler, five stretch-press measuring devices, the small-size bypass aircraft, a work table, two knuckle bearings, a hinge, a sliding bearing, an optical axis supporting seat, two axial spacing rings, a fixed axis, an optical axis and three steel poles. In the invention, a sensor is orthogonally arranged according to a coordinate system of a machine body, the torque sensor is arranged along the axis direction of the horizontal machine body, a stretch-press sensor is arranged by adopting the knuckle bearing and the hinge, the torque sensor is connected with the small-size bypass aircraft through the universal joint coupler, and the stretch-press sensor is connected with the small-size bypass aircraft through the knuckle bearing, and therefore, the measurement of the quality, the mass center position, the engine thrust, the pitching moment, the rolling moment and the yawing moment of the small-size bypass aircraft is realized.

Disclosed is an anti-rolling ship. The anti-rolling ship comprises a hull having an engine room; and a tank which is mounted on the upper surface of the engine room, and which has an interior for partially containing a fluid therein. The fluid contained in the tank reciprocates when the vessel rolls, generating anti-rolling moment, and thus effectively reduces rolling of the ship. In addition, the space formed on the upper surface of the engine room of the ship is utilized as a tank accommodating portion to achieve improved space utilization.