Abstract:
A sensor pad for controlling the deployment of an automobile airbag. Weight sensing pad 10 is used in the seat 54 of an automobile, (not illustrated), to detect the presence of an occupant on the seat. Weight sensing pad 10 is used in conjunction with the vehicle's airbag control module in order to allow deployment of the airbag, in the event of a collision, only if the seat is occupied by a person of a preselected weight. Weight sensing pad 10 is defined by a bladder member 15 having an interior volume subdivided into a plurality of individual cells 42 in fluid communication with each other and that is filled with a non-compressible fluid 18, such as silicon or a silica gel of medium viscosity. A pressure tube 22 is in fluid communication with bladder 15 and is in further fluid communication with a pressure activated electronic transducer 26 which in turn is in electronic communication with the airbag controller 30. When a person sits upon weight sensing pad 10, there is a volumetric displacement of fluid 18 that provides a pressure change in the bladder member. If there is a sufficient pressure change due to the volumetric displacement of fluid to activate transducer 26, transducer 26 sends a signal to air bag controller 30. Electronic transducer 26 is selected to generate a signal upon detection of pressure resultant from the volumetric displacement of fluid 18 from bladder 15 expected from the average size adult of approximately one hundred pounds or heavier.
Abstract:
A tactile sensor comprises a sensing bladder in pneumatic communication with a first diaphragm side of a pneumatic diaphragm via a first fluid; the pneumatic diaphragm being actuatable by a displacement of the first fluid within the sensing bladder; the pneumatic diaphragm further comprising a second diaphragm side in fluid isolation from the first diaphragm side; the second diaphragm side being pneumatically biased against the first diaphragm side, and the second diaphragm side and the first diaphragm side of the pneumatic diaphragm each being in pneumatic communication with an external environment.
Abstract:
A sensor pad for controlling the deployment of an automobile airbag. Weight sensing pad 10 is used in the seat 54 of an automobile, (not illustrated), to detect the presence of an occupant on the seat. Weight sensing pad 10 is used in conjunction with the vehicle's airbag control module in order to allow deployment of the airbag, in the event of a collision, only if the seat is occupied by a person of a preselected weight. Weight sensing pad 10 is defined by a bladder member 15 having an interior volume subdivided into a plurality of individual cells 42 in fluid communication with each other and that is filled with a non-compressible fluid 18, such as silicon or a silica gel of medium viscosity. A pressure tube 22 is in fluid communication with bladder 15 and is in further fluid communication with a pressure activated electronic transducer 26 which in turn is in electronic communication with the airbag controller 30. When a person sits upon weight sensing pad 10, there is a volumetric displacement of fluid 18 that provides a pressure change in the bladder member. If there is a sufficient pressure change due to the volumetric displacement of fluid to activate transducer 26, transducer 26 sends a signal to air bag controller 30. Electronic transducer 26 is selected to generate a signal upon detection of pressure resultant from the volumetric displacement of fluid 18 from bladder 15 expected from the average size adult of approximately one hundred pounds or heavier.
Abstract:
A system and method for measuring contact pressures between two surfaces, and especially, between the body and a device resting on the body, e.g., the skin and a breathable gas mask. A deformable, resilient probe having a flow passage therein is initially placed between the two surfaces such that the flow passage is blocked. Fluid pressure within the probe is then increased until the pressure in the probe overcomes the contact pressure between the two surfaces, such that fluid begins to flow through the flow passage in the probe. The pressure at which the fluid begins to flow through the flow passage in the probe is recorded as the contact pressure between the two surfaces. Contact pressure maps created using this apparatus and method may be used to create anthropometric models of the face and other body parts.
Abstract:
A fluid-filled elastic hollow body 2, includes a pressure sensor 4 for detecting the pressure of the fluid in the elastic hollow body, and an adapter 6 for coupling the elastic hollow body to an external movable member. The elastic hollow body 2, having a hollow sphere portion 2a having a roughly constant wall thickness, is deformed when an external contact load is applied causing a rise in its inner pressure detected by the pressure sensor 4. The invention provides: (1) that the sensor can accurately measure a contact load without being influenced by a change in direction of force measured; (2) that it can be attached easily and measure a load immediately after attachment; (3) that it is resistant against instantaneous shock load; (4) that it can easily model a substance when it comes in contact therewith; and (5) that its sensitivity does not deteriorate.
Abstract:
A force sensing device for use in analyzing the movement of a person or animal. The device includes a base and a platform supported on the base by ball casters. The platform includes first and second plates with pneumatic tubing positioned between the plates. Forces on the platform result in compression of the pneumatic tubing, and the corresponding pressure changes in the pneumatic tubing are measured by associated pressure transducers. The device includes side rails which extend upwardly from the base and surround the platform. The side rails each include first and second plates with pneumatic tubing positioned between the plates. Side-to-side movement of the platform against the side rails results in compression of the pneumatic tubing in the side rails, and associated pressure transducers measure the corresponding pressure changes. The measurements from the pressure transducers are converted into force measurements and used to analyze the movement of the person or animal.
Abstract:
An improved weight estimation apparatus includes a closed elastomeric bladder filled with fluid and installed in the foam cushion of a vehicle seat bottom, with at least one pressure sensor installed in a closed exit port of the bladder. A temperature sensor disposed in proximity to the bladder provides a temperature signal, and a controller estimates the weight of the occupant based on the temperature and pressure signals. The pressure sensor is preferably configured to sense the gage pressure--that is, the differential pressure between the fluid and atmospheric pressure--at the center of gravity of the fluid in order to provide a stable output independent of changing atmospheric pressure and changing orientation of the bladder due to vehicle pitch and roll.
Abstract:
A force sensor assembly incorporates an integrated plunger to provide an economical assembly which can be calibrated and mounted as a single unit. The force sensor assembly utilizes a retainer to movably capture a solid interface within an opening in the retainer. The solid interface includes a flange positioned within the assembly below the retainer opening. The flange dimensions are greater than the retainer opening to retain the solid interface within the assembly. The retainer is attached to a housing body having a gel filled cavity underlying the retainer opening. A diaphragm free floats on the gel within the housing body and contacts the solid interface. The gel transmits a force exerted on the diaphragm from the solid interface to a pressure sensor mounted at the base of the housing body cavity. A ceramic substrate having an integrated resistor network supports the pressure sensor and an amplifier. The pressure sensor and accompanying electronic components provide a conditioned electrical signal corresponding to the force applied to the solid interface.
Abstract:
To measure pressure acting on a support (1), a sealed bag (2) which is filled with a fluid and has flexible bag walls (9, 10), and which is arranged on the support (1) and whose interior communicates with a flexible capillary tube (4, 4'), is used as a sensor. Connected to the free end of the flexible capillary tube (4, 4') is an evaluation device which detects pressure variation, it being possible for the end of the flexible capillary tube (4, 4') to be plugged into a block (5). The block has a bore (6) which continues the channel of the flexible capillary tube (4, 4') and is sealed at its end not: subjected to the flexible capillary tube (4, 4') by a diaphragm (7). The diaphragm bulges outwards in the event of a reduction in the volume of the bag (2). The extent of the outward bulging of the diaphragm (7) can be determined by an optical detector (15, 16).
Abstract:
A joint including an elastic connecting device includes a rigid element and a rigid outer element receiving the rigid inner element such that the rigid inner element is movable with respect to the rigid outer element. The rigid inner element and the rigid outer element have respective outer and inner facing surfaces. A bore is disposed in one of the rigid inner element and the rigid outer element, and the bore opens to one of the respective outer and inner facing surfaces. A force/pressure sensing arrangement is disposed in the bore, and a substantially incompressible fluid is sealed in the bore. Elastomeric material is disposed between the rigid outer element and the rigid inner element in force/pressure transmission contact with the force/pressure sensing arrangement. The rigid inner element has a central passage and a radially enlarged portion, and the inner surface of the rigid outer element has a contour generally complementary to the outer surface of the rigid inner element, so as to form an annular intermediate space at least partially occupied by the elastomeric material.