Abstract: A roll-over detector for vehicles includes a first accelerometer mounted on a first axle of the vehicle, a second accelerometer mounted on a second axle of the vehicle, and a third accelerometer mounted on a third axle of the vehicle. A controller compares data received from the first and second accelerometers and actuates a safety device to prevent a roll-over condition if the differences between the data exceed a predetermined value. The controller utilizes data from the third accelerometer to account for the effect of road conditions on the variations between the data from the first and second accelerometers.

Abstract: A drive line vibration sensor includes an emitter, a receiver, and a controller. The emitter and receiver are mounted in a differential manner such that drive line vibrations cause the emitter to vibrate at a different frequency than the receiver. In operation the emitter transmits a signal to the receiver such that the differential movement of the transmitter relative to the receiver produces a variation in the signal received by the receiver which is identifiable by the controller. In another embodiment, the emitter pulses the signal such that the frequency of the vibration can be determined. A recording device is preferably in communication with the controller to record the variation in the signal to provide an inexpensive diagnostic and maintenance system which can record the overall operation of a drive line under actual operational conditions.

Abstract: A drive line vibration sensor includes a mercury switch, a controller, and a warning device. The mercury switch is preferably positioned such that it is minimally affected by radial acceleration yet remains sensitive to longitudinal accelerations along the longitudinal axis of a drive line. To minimize the affect of radial acceleration, the mercury switch is attached to the drive line such that the mercury switch is tilted relative to the longitudinal axis such that the radial acceleration of the drive line does not activate the mercury switch. If the mercury switch experiences a predetermined acceleration, the controller identifies that the mercury switch is activated and the controller then awakes and activates a transmitter, such as a radio frequency (RF) transmitter to send a signal to a remote warning device such as a warning light.

Abstract: A method of monitoring sounds of a driveline includes detecting a sound from a driveline, comparing the detected sound with-a predicted sound of the driveline, and, when the detected sound differs from the predicted sound of the driveline, sending a warning signal that the driveline may be experiencing a problem. The method of monitoring the sounds of a driveline is used to determine the physical condition of the driveline. The present invention allows the driver to check the physical condition of a driveline while operating the vehicle. A sound detector detects sounds from a driveline and send sound signals to a control which receives the sound signals, performs computations based on the detected sounds, and compares the computations with predicted sounds of the driveline. The control sends warning signals to a display, when the detected sounds differ from the predicted sounds.

Abstract: A system for electronically measuring the distance that a wheel has traveled can be used on a tractor-trailer combination vehicle to independently monitor mileages for the tractor and the trailer. An axle on the tractor and an axle on the trailer each has a hub odometer system which can electronically measure and store mileages for its respective axle. The system is mounted on a wheel and includes a signal generating device and a semiconductor unit. The signal generating device generates an electrical signal proportional to the number of wheel revolutions and the semiconductor unit receives, counts, and stores the electrical signals. The electrical signals are relayed to an output device. The system can also be used on other types of vehicle.

Abstract: A method and apparatus for monitoring slack adjustment for braking in a vehicle is applicable to either drum or disc brake assemblies. The vehicle has several axle assemblies each with a pair of brake assemblies. A typical disc brake assembly includes a rotating disc, an actuator, a caliper with a brake lining supported on a backing plate, and a slack adjuster for adjusting the travel distance of the caliper to the disc. The actuator moves the brake linings of the caliper into contact with the rotating disc to brake the vehicle, resulting in a temperature increase in the brake linings. Temperature sensors are embedded in the brake linings of each brake assembly on each axle of the vehicle. The temperature of each brake lining is measured and compared with the temperature of the brake lining of its brake pair on the same axle. If the ratio of the two brake lining temperatures achieves a predetermined limit, a slack adjuster is deemed out of adjustment and a warning signal is sent to the vehicle operator.

Abstract: A system and method for controlling the navigation of surface based vehicle uses a route that is obtained by manually driving the vehicle over the route to collect data defining the absolute position of the vehicle at various positions along the route. The collected data is smoothed to provide a consistent route to be followed. The smoothed data is subsequently used to automatically guide the vehicle over the route.

Abstract: A brake lining wear indicator utilizes a temperature sensor assembly embedded in a brake lining of a drum brake assembly. The temperature sensor assembly includes two temperature sensors with a first temperature sensor located at a first distance X from the wear surface of the brake lining and a second temperature sensor located at a second distance X+d from the wear surface. A timing device measures the time period for the first temperature sensor to reach a first predetermined temperature and measures the time period for the second temperature sensor to reach a second predetermined temperature. The remaining useful thickness of the brake lining is determined based on the ratio of the respective time periods. Thus, the indicator provides a time-temperature based determination of when the brake linings should be replaced.

Abstract: A system for detecting a drowsy driver includes an axle with a sensor for measuring the movement of the axle and for producing an axle signal. The sensor typically measures any or all of the following: the lateral acceleration of the axle, the fore-aft acceleration of the axle, or the vehicle speed. A central processing unit compares the axle signal derived from the sensor measurements to a pre-determined drowsy threshold and an indicator indicates to the driver that drowsiness has been detected when the axle signal exceeds the pre-determined drowsy threshold.

Abstract: A system for determining the weight of a vehicle includes a first axle subject to a relatively fixed axle weight. Typically, this axle is a front steering axle for a tractor-trailer combination vehicle. The load on this axle is considered known as the load does not vary significantly during the operation of the vehicle. A first accelerometer is supported on the first axle and measures the vertical acceleration of the first axle producing a first signal. Each additional axle on the vehicle, including any single rear or tandem drive axles and any trailer axles, also supports an accelerometer. The accelerometers on each of these additional axles measure the vertical acceleration of its respective axle. Each of these additional accelerometers produces a signal representative of its respective axle accelerations and these signals are combined to produce a second signal. A processor determines the vehicle weight by comparing the second signal to the first signal.

Abstract: A system (400) for positioning and navigating an autonomous vehicle (310) allows the vehicle (310) to travel between locations. Position information (432) is derived from global positioning system satellites (200, 202, 204, and 206) or other sources (624) when the satellites (200, 202, 204, and 206) are not in the view of the vehicle (310). Navigation of the vehicle (310) is obtained using the position information (432), route information (414), obstacle detection and avoidance data (416), and on board vehicle data (908 and 910).

Abstract: A method to estimate the thickness of a brake lining based on the periodic sampling of the output of a temperature sensor embedded in the brake lining. A temperature histogram is created which is compared to calibration histograms stored in an electronic processing unit to yield an estimated brake lining thickness which is transmitted to the vehicle cab or to another on-board electronics unit. A brake wear factor is calculated from the temperature histogram by multiplying the average value of each temperature range by the frequency of occurrence and then summing the results.

Abstract: A method for detection of wear of a brake lining using a temperature sensor embedded in a brake lining adjacent to a brake table. A temperature versus time history recorded upon application of the brake system is transmitted to a microprocessor based processing unit which estimates the thickness of the remaining brake lining based on comparison with calibration data stored in the processing unit.

Abstract: A system for generating a path allows a vehicle to traverse a predetermined route. The system stores route data for the predetermined route. The route data identifies a series of contiguous path segments that form the predetermined route. The route data also identifies a series of nodes located at the beginning and the end of the predetermined route and between adjacent path segments. Each path segment represents a series of postures along the predetermined route. Each posture identifies a position, a heading, and a curvature for the vehicle at a particular point along the predetermined route. The system stores the path segments and nodes as compressed path data. In one embodiment, the compressed path data is a function that is continuous in posture, i.e., continuous in position, heading and curvature. The system retrieves the compressed path data and generates a series of postures from the retrieved compressed path data to allow the vehicle to traverse the predetermined route.

Abstract: An apparatus and method for controlling a surface-based vehicle provides three operational modes: a manual operation, a tele-operation, and an autonomous operation. In manual operation, an operator directly manipulates vehicle controls on the vehicle. In tele-operation, the operator controls the vehicle from a remote position. In autonomous operation, the vehicle controls itself based on its position and a predetermined path. The apparatus and method of the present invention provides an orderly transition between manual operation, tele-operation, and autonomous operation of the vehicle.

Abstract: A system and method for controlling an autonomously navigated vehicle uses a vehicle manager to control vehicle subsystems and to respond to commands from either a vehicle navigation system or a remote control panel. The vehicle manager controls vehicle subsystems including a speed control subsystem, a steering control subsystem, an auxiliary control subsystem, and a monitor subsystem. The speed control subsystem controls the speed of the vehicle in response to a speed command from the vehicle manager. The steering control subsystem controls the steering angle of the vehicle in response to a steering command from the vehicle manager. The auxiliary control subsystem controls auxiliary functions of the vehicle in response to an auxiliary command from the vehicle manager. The monitor subsystem monitors the status of each of the other subsystems and provides the status to the vehicle manager.

Abstract: Systems and methods allow for the accurate determination of the terrestrial position of an autonomous vehicle in real time. A first position estimate of the vehicle 102 is derived from satellites of a global positioning system and/or a pseudolite(s). The pseudolite(s) may be used exclusively when the satellites are not in the view of the vehicle. A second position estimate is derived from an inertial reference unit and/or a vehicle odometer. The first and second position estimates are combined and filtered using novel techniques to derive a more accurate third position estimate of the vehicle's position. Accordingly, accurate autonomous navigation of the vehicle can be effectuated using the third position estimate.

Abstract: An apparatus and method for navigating a vehicle along a predetermined route use route data and path data to define the predetermined route. The route data represents one or more contiguous path segments between adjacent nodes along the predetermined route. The path data includes postures of the vehicle along each of the path segments. The postures define the desired position, heading, curvature and speed of vehicle at various locations along the path segments. The apparatus and method use the posture information to generate and track a path thereby allowing the vehicle to navigate along the predetermined route.

Abstract: A system (400) for positioning and navigating an autonomous vehicle (310) allows the vehicle (310) to travel between locations. Position information (432) is derived from global positioning system satellites (200, 202, 204, and 206) or other sources (624) when the satellites (200, 202, 204, and 206) are not in the view of the vehicle (310). Navigation of the vehicle (310) is obtained using the position information (432), route information (414), obstacle detection and avoidance data (416), and on board vehicle data (908 and 910).

Abstract: A method and apparatus for computing a precise position estimate for a receiver at or near the surface of the Earth uses a inertial reference unit associated with the receiver and a satellite-based navigation system. The satellite-based navigation system is used to determine a position estimate for the receiver at consecutive positions along its path of motion. The inertial reference unit is used to determine velocity vectors for the receiver. Each velocity vector corresponds to travel of the receiver between the consecutive positions. The velocity vectors from the inertial reference unit are used to refine the position estimates of the satellite-based navigation system to obtain precise position estimates.