Abstract: A residual charge traffic sensor for monitoring the number and speed of vehicles traveling in multiple lanes of a roadway includes a housing containing a cavity, a conductive mounting bar adapted to fit within the cavity, at least two sensing elements mounted on the mounting bar which generate a signal when impacted by a vehicle tire, a transmission cable connected with the sensing elements for transmitting the electric signals generated by the sensing elements, and analyzing equipment for evaluating, displaying, and recording the data generated by the sensing elements. Signals are transmitted through every other wire of the transmission cable to minimize cross-talk between the signal carrying wires.

Abstract: A system for detecting an object located on a travelling path even in bad weather or during nighttime in which conducting wires having a predetermined impedance value are laid along a travelling path, and a signal is supplied to the conducting wires from a signal source. If a vehicle exists on the path, the impedance of the conducting wires changes at the position where the vehicle is present. A signal reflected from the impedance change position is detected by a detector. The position of the vehicle can be determined from the timing of the received reflection signal. It is also possible to detect a vehicle changing lanes or the like by means of a plurality of conductive wires laid along the travelling path. Instead of a conducting wire, an optical fiber may be provided for determining the position of a vehicle using the refractive index change in the optical fiber due to the weight of the vehicle.

Abstract: An underground vehicle sensing system extends below a vehicle travel surface to detect the presence of a vehicle. A conduit extends substantially horizontally underground from an access hole placed at the side of the vehicle travel surface. A plurality of sensors are spaced apart in the conduit to detect localized changes in the magnetic field. A plurality of sections house the probes and wiring to orient and position the probes. Sections detachably clip together to form a lightweight support structure and may be added one by one through the access hole. Lightweight extension members are utilized in some configurations between the support sections for positioning and supporting the probes.

Abstract: The naturally occurring residual charge of a dielectric is utilized to establish a static electric field adapted to be disturbed by a conductive member upon occurrence of an event, such as, for example, the passage of a vehicle tire over the conductive member. Disturbance of the electric field results in the generation of a pulse that can be monitored. A traffic sensor for monitoring the number and speed of vehicles traveling in multiple lanes of a roadway employing dielectrics with naturally occurring residual charge includes a housing containing a cavity, a conductive mounting bar adapted to fit within the cavity, at least two sensing elements including the dielectrics mounted on the mounting bar so as to generate a signal when impacted by a vehicle tire. A transmission cable connects with the sensing elements for transmitting the electric signals generated by the sensing elements to analyzing equipment for evaluating, displaying, and recording the data generated by the sensing elements.

Abstract: A detector for detecting a characteristic and a speed of a vehicle includes a first magnetic field sensor for generating a first analog signal indicative of changes in magnetic field strength adjacent the first sensor in response to the vehicle passing. A differentiating circuit differentiates the first analog signal and produces a first output that changes binary state in response to detecting a predetermined change in the differentiated first analog signal. A counter accumulates values at a predetermined rate and a microprocessor stores values of the counter corresponding to each change in the binary state of the first output of the differentiating circuit. The microprocessor converts the stored counter values into a first time series profile corresponding to changes in the first output of the differentiating circuit and accumulates and stores a count of a characteristic of the passing vehicle based on the first time series profile.

Abstract: A traffic sensor for dispostion across a lane or lanes of a roadway includes a pliable strip within which is housed a flexible carrier which in turn supports electrical sensors and coaxial cables. The components are in circuit with a roadside located recording device. Vehicle imparted loads applied to the strip and carrier are counteracted by an inelastic member extending lengthwise of the strip to prevent erroneous electrical impulses. The inelastic is embodied in strands of material embedded in the carrier. Fastener elements extend through the strip for insertion into the roadway for strip retention.

Abstract: A detection device for data relating to the passage of vehicles over a road. The detection device is to be placed in a groove provided in the upper portion of the road and comprises a first profiled strip provided with an upper cavity in a U-shape, and a piezoelectric cable of the coaxial type arranged in the bottom of the cavity of the first profiled strip. A second profiled strip is arranged in the cavity of the first profiled strip on top of the coaxial cable. The second strip has a shape and dimensions such that it fills up the remaining volume of the cavity above the cable and seals this cavity.

Abstract: A work zone intrusion alarm system which sounds a siren to warn highway workers in the event a vehicle enters a work zone. Workers may thus react to errant vehicles in time to avoid injury. The work zone intrusion alarm system is composed of a series of pneumatic sensing lines arranged within a highway work zone adjacent a perimeter separating the work zone from oncoming traffic. The sensing lines are connected at junction boxes which include pressure switches. A warning alarm including a siren is activated by the pressure switch upon the compression of a sensing line when driven over by an errant vehicle.

Abstract: A pressure sensitive switch mat capable of interconnection with other such switch mats on all sides to eliminate non-activation zones as disclosed. The switch mat has a main switch mat portion and an activation edge on all sides of the switch mat. The activation edge includes a connector retainer lip, an actuation platform and an end portion. When an actuation force is applied to the actuation platform, the switch mat is actuated. A bridge connector for connecting adjacent pressure sensitive switch mats to eliminate non-activation zones therebetween is disclosed. Additionally, a control circuit for the switch mat system that has an integrity monitoring system for providing reliable control of the switch mat system is disclosed.

Abstract: A bidirectional road traffic sensor include several respective lengths of coaxial piezoelectric cable each having a conductive core, a conductive polymer surrounding the core, a conductive sheath therearound and an electrically non-conductive jacket therearound. The cables are spliced together such that conductive core and conductive sheath of one length of piezoelectric cable is spliced respectively to the conductive sheath and conductive core of another piezoelectric cable. The splices are encapsulated in an electrically non-conductive material so that the spliced lengths of piezoelectric cables respectively constitutes positive, neutral and negative piezoelectric sensors. Pressure changes in the piezoelectric sensors are caused by vehicle passage thereover. In such a manner, electrical pulses are responsively produced by passage of vehicles traversing respective detection zones defined by the sensors and moving in respective particular directions so that such passage of such vehicles may be registered.

Abstract: A linear roadway vehicle sensor for sensing vehicular traffic thereover includes a flexible carrier comprising an elongated flat elastomeric member having upper and lower surfaces and at least one groove in one of the surfaces. An elongated pressure sensor is carried in the one groove and a linear weight is distributed along and secured to the length of said flexible carrier. The weight has a weight per unit length which is sufficient to maintain said sensor on said roadway and substantially immune to lifting from the roadway because of air flow effects and turbulence caused by vehicles.

Abstract: A linear roadway vehicle sensor for sensing vehicular traffic thereover includes a flexible carrier member comprising an elongated flat elastomeric member having upper and lower surfaces, a recess formed in the lower surface. The recess has a first top surface and a linear weight is distributed along the length of the flexible carrier. An adhesive secures the linear weight in the recess in said flexible carrier. The weight has a second top surface and a weight per unit length which is sufficient to maintain the sensor on said roadway and substantially immune to lifting from the roadway because of air flow effects and turbulence caused by vehicles, and one or more sensor grooves formed in the top surfaces and an elongated sensor in the one or more sensor grooves and between the elastomeric member and the linear weight means.

Abstract: A linear roadway sensor in which a distributed weight member has a weight per unit length which is sufficient to maintain the sensor on the roadway and substantially immune to air effects generated by vehicular traffic on the roadway. A method of safely installing the sensor is to pivot one end at the edge of the roadway and then swing the sensor on an arc then allowing the weight to maintain the sensor on the roadway.

Abstract: A wheel sensing treadle of high sensitivity includes a thin membrane strip having a top non-conductive membrane and a bottom non-conductive membrane, the membranes being generally parallel, spaced apart, and of extended length. A large number of switches are closely positioned along the length of the membranes. Each switch includes two thin conductive contacts formed respectively on each membrane by printing with conductive ink. A similarly-printed electrical lead connects respectively to each the switch contacts. The membrane strip is sandwiched between a rigid base and a resilient cover to form a treadle of extended length. The switch contact leads are connected in an X Y matrix, each switch having one contact connected to an X line and the other contact of the switch connected to a Y line of the matrix whereby each switch in the treadle has a unique X, Y address and can be rapidly an repetitively scanned by a computer.

Abstract: A traffic counting cord has a plurality of sections designed to be identical in physical characteristics, set-up procedures, durability and performance as a road tube. Each section has a portion with conductive upper and lower members and a portion with non-conductive upper and lower members. The upper and lower members are separated by resilient, non-conductive material. Embedded within the members are a plurality of wires insulated with nylon or other material and at least one non-insulated wire which is in contact with the conductive member. A count occurs when traffic impacting the cord causes the upper and lower members of a section to make contact. Individual counts for each lane can be obtained by cross-wiring the sections, so that the uninsulated conductors of each section are routed to a counter through insulated conductors or wires of the other sections. Any even or odd number of lanes, typically four, six, or eight lanes can be accommodated, although there is no theoretical limit.

Abstract: A traffic counting cord has a plurality of sections designed to be identical in physical characteristics, set-up procedures, durability and performance as a road tube. Each section has a portion with conductive upper and lower members and a portion with non-conductive upper and lower members. The upper and lower members are separated by resilient, non-conductive material. Embedded within the members are a plurality of wires insulated with nylon or other material and at least one non-insulated wire which is in contact with the conductive member. A count occurs when traffic impacting the cord causes the upper and lower members of a section to make contact. Individual counts for each lane can be obtained by cross-wiring the sections, so that the uninsulated conductors of each section are routed to a counter through insulated conductors or wires of the other sections. Any even or odd number of lanes, typically four, six, or eight lanes can be accomodated, although there is no theoretical limit.

Abstract: A system used for monitoring the flow and speed of traffic has a strip member (1) comprising electrical contacts (3, 7) on distinct layers (2, 6) separated by a dielectric spacer layer (4), such that, when a vehicle drives over the strip, the weight of the vehicle on the strip closes the contact through holes (5) in the dielectric spacer to cause a monitoring and/or timing means to be activated and subsequently deactivated. The monitoring and/or timing means is programmable to distinguish vehicle types and between a plurality of vehicles passing over the strip at the same time.

Abstract: Disclosed is an improved system for quick detection of driver impairment as evidenced by the driver's inability to keep a vehicle on an assigned course, utilizes parallel strips defining a relatively narrow lane through which the driver is to operate the vehicle. The strips and their associated equipment, are readily portable, and are thus adapted to be set up by police officers at any location desired, in a minimum amount of time, thereby permitting spot checks with little or no advance warning to motorists approaching the check point. The strips are hollow, and contain pressure chambers, the volume of which is reduced when a vehicle tire crosses or rides along on top of one of the strips. Reduction of the pressure chamber volume is adapted to carry air pressure through tubes to locations near to or remote from the hollow strips to actuate electrical switches located at predetermined intervals along and out from the traffic lane defined by the hollow strips.

Abstract: A vehicle sensing device comprises an electrically insulating elongate carrier (1) with two electrical conductors (2,3) extending longitudinally of the carrier and spaced apart transversely of the carrier so that there is no direct contact between the conductors. A strip (14) of elastomeric material overlies both conductors and is in contact therewith in areas distributed along substantially the whole of their length. The strip (4) being such that in the absence of a given level of applied pressure the strip forms a barrier of high electrical resistance between the conductors, and that in the presence of applied pressure above the given level in any region of the strip, that region of the strip forms an electrically conductive path between the conductors. The carrier, conductors and strip are wholly encapsulated in a jacket of water-resistance and abrasion-resistance elastomeric material.

Abstract: The device comprises: an elongate support part (4) suitable for being embedded in the path and having a low upstanding wall (17) running along the edge thereof; a plate (30) cantilevered out from the low wall (17) with its cantilevered portion being subdivided into tongues (38) by slots (39) which extend perpendicularly to the longitudinal direction of the support part (4); pressure transducers received in the support part (4) beneath said tongues (38); resilient means between the tongues (38) and the transducers; and electrical connection means (350) making connections with the pressure transducers.

Abstract: A system for quick detection of driver impairment as evidenced by the driver's inability to keep a vehicle on an assigned course, utilizes parallel strips defining a relatively narrow lane through which the driver is to operate the vehicle. The strips, and their associated equipment, are readily portable, and are thus adapted to be set up by police officers at any location desired, in a minimum amount of time, thereby permitting spot checks with little or no advance warning to motorists passing the check point. The strips are hollow, and contain pressure chambers, the volume of which is reduced whenever a vehicle tire crosses or rides along one of the strips. Reduction of the pressure chamber volume is adapted to actuate switches, strategically located at predetermined intervals along the length of the respective strips. The switches in turn close circuits, when so activated, to recording devices, radar equipmet, or any other checking apparatus favored by the authorities.

Abstract: Measurement of the area and shape of contact between a vehicle's wheels or racks and the surface over which it moves is automated by having the vehicle drive over an array of switches connected in a matrix including X and Y conductors. The matrix is systematically scanned to produce a pulse train with one pulse therein for each closed switch, with the locations of said pulses indicating the shape of the area of contact. Circuit means are provided to count the number of pulses to indicate the area of contact and to operate a small scale display which indicates the shape of the area of contact.

Abstract: A pressure-responsive electric switch assembly provided with an elongated pneumatic tube of elastomeric foam material impermeable to air, one end of the tube being plugged and the other having a sleeve therein whose inner end is covered by a membrane to thereby seal the tube. The tube has a relatively thick, deformable wall whereby a slight manual pressure applied thereto gives rise to a substantial change in the internal volume of the sealed tube to dilate the membrane. A microswitch disposed within the sleeve has an actuating element operatively coupled to the membrane such that when manual pressure is applied to the tube, the switch is actuated.

Abstract: To prevent inaccurate weighing on a platform scale in the event that a driver of a motor vehicle has purposefully or inadvertently positioned his vehicle with one or more of the vehicle wheels located off of the weighing platform, the platform scale is provided with an alarm system which comprises a weight responsive mat switch located in the roadbed along the perimeter of the weighing platform, a signal located in the proximity of the scale operator, and means interconnecting the mat switch and the signal for actuating the signal and alerting the scale operator in response to one or more wheels of the motor vehicle coming into engagement with the mat switch.

Abstract: A treadleplate for use in an automatic carwash system for regulating the length of time a cleaning solution is sprayed on the tires of a passing vehicle in direct relationship to the size of the vehicle tire. A horizontal base plate is mounted on the carwash floor in the path of one of the vehicle tires. A contact plate is pivotally mounted on the base plate and is movable from a normal inclined, at-rest position to a horizontal depressed position when rolled over by the vehicle tire. The contact plate is formed with a stepped outer swinging edge which provides a series of transversely spaced contact zones of varying tire contact length. These zones are adapted to be selectively engaged by one of the tires of a vehicle moving through the carwash which depresses the contact plate and actuates a cleaning solution control valve. The particular zone which is engaged by the tire is in direct relationship to the transverse spacing or track of the particular vehicle moving through the carwash.

Abstract: A pneumatically-operated bell, such as is commonly used in service stations, has twin pneumatic hoses. The first is a conventional signal hose, actuating the bell when compressed. The second hose is laid parallel to the first and, when compressed, prevents actuation of the bell by the first hose for a predetermined period. In a first embodiment, the second hose opens a switch in the bell's electric circuit. In a second embodiment, the second hose actuates a valve to block air flow through the first hose to prevent its actuating the bell. As a result, vehicles exiting the service station compress the second hose first and thus no signal is produced, while vehicles entering the station produce a signal only when the front wheels cross the hoses. Thus false signals from exiting vehicles and false double signals are prevented.

Abstract: A valve which produces an electrical signal upon pressure changes in which a diaphragm having an aperture contacts a leaf spring having a projection thereon. The valve provides for both controlled leakage of air, and intake of air in semi-closed static air signal system, particularly useful in vehicle driving instruction and scoring devices.