Abstract: A vehicle suspension comprises dampers changeable between low and high damping modes and normally operated in the low damping mode. A damper control stores a plurality of sets of reference numbers as a function of vehicle velocity, the reference numbers of each set representing limit values of throttle velocity for the low damping mode for a given transmission gear mode. The reference numbers of each set increase in value with increasing vehicle velocity in a continuously non-linear manner so as to compensate for the decreasing acceleration and body lift produced by a given throttle velocity as vehicle velocity increases. The control changes the damper from low to high damping during vehicle acceleration for a predetermined time when the throttle velocity exceeds a throttle velocity limit reference derived from the reference number corresponding to the vehicle velocity in the set corresponding to the selected transmission gear mode.

Abstract: A motor vehicle suspension system has a damper with a member rotatable through positions producing separate discrete damping characteristics. Feedback apparatus comprises a contact pad for each position, a brush rotating with the rotatable member, and an electric circuit generating an output voltage in a first voltage range when the brush does not contact a contact pad and in a second range when it does. The output voltage is repeatedly sampled to control a position count. A count control increments the count with the first sample in the second range following a predetermined number of consecutive samples in the first range but prevents further increment of the count until after a predetermined number of consecutive samples in the second range. The rotatable member can thus be stopped immediately upon the first detection of the selected position while the counting control is changed only once in each new position of the rotatable member.

Abstract: An ignition timing system activates combustion ignition apparatus in a combustion chamber at times established at least partly in response to a knock retard value. The knock retard value is normally modified in response to a knock signal generated by a knock sensor during a knock window corresponding to a predetermined crankshaft rotational angle in which knock is to be sensed. However, if the knock signal is determined to be present at the beginning of an occurrence of the knock window, modification of the knock retard value in response to the knock signal is prevented during that occurrence of the knock window, since a knock signal already present at the beginning of the knock window is assumed to be noise.

Abstract: A fill sensor for a paint gun provides a light sensor opposite a light source in a housing surrounding a transparent portion of paint gun overflow line so that reception by the light sensor of light radiated from the light source through the transparent portion of the overflow line is blocked when the paint gun is filled and the paint enters the overflow line, as indicated by a change from a first signal to a second signal from an electric circuit including the light snesor. A preferred embodiment of the invention uses a CdSe.sub.4 photo-resistor with a large aperture which is not blocked by small objects in the transparent portion of the overflow line and has a comparatively slow response for inherent signal low pass filtering. The electric circuit is adapted to operate through an intrinsically safe barrier for use in a manufacturing environment.

Abstract: A vehicle suspension comprises dampers changeable between low and high damping modes and normally operated in the low damping mode. A damper control stores a plurality of sets of reference numbers as a function of vehicle velocity, the reference numbers of each set representing limit values of throttle velocity for the low damping mode for a given transmission gear mode. The reference numbers of each set increase in value with increasing vehicle velocity in a continuously non-linear manner so as to compensate for the decreasing acceleration and body lift produced by a given throttle velocity as vehicle velocity increases. The control changes the damper from low to high damping during vehicle acceleration for a predetermined time when the throtle velocity exceeds a throttle velocity limit reference derived from the reference number corresponding to the vehicle velocity in the set corresponding to the selected transmission gear mode.

Abstract: Orange peel or texture of a painted surface is measured by scanning a light beam across the surface and receiving the reflected beam on an area detector generating a signal having a first component varying with surface slope variations in the painted surface and a second component due to scan rate. Apparatus is provided for orienting the light beam relative to the painted surface so as to be reflected therefrom to the detector area without re-reflection from the painted surface; and a converging lens converges the light beam on the area detector. A portable, surface contacting embodiment uses a plurality of projecting feet for orientation to the painted surface and relies on the converging lens for convergence. In a non-contact embodiment, variations in orientation and curvature of the surface are detected by the second component of the signal and compensated for in closed loop control of a mirror and the converging lens to dynamically converge the beam on the area detector.

Abstract: A motor vehicle suspension system has a damper with a member rotatable through positions producing separate discrete damping characteristics. Feedback apparatus comprises a contact pad for each position, a brush rotating with the rotatable member, and an electric circuit generating an output voltage in a first voltage range when the brush does not contact a contact pad and in a second range when it does. The output voltage is repeatedly sampled to control a position count. An overrun detector responds to a predetermined change of the sampled output voltage from the second range to the first voltage range after deactivation of the motor at a selected contact pad to restart the motor so as to resume rotation of the rotatable member toward the selected contact pad.

Abstract: A motor vehicle suspension system in which a motor drives a rotatable member through a plurality of rotational positions producing distinct damping characteristics provides a position feedback voltage on a single feedback line for low cost, easier packaging and greater reliability. Contact pads for the rotational positions are separated by electrically insulating regions; an electric contact member moves circularly with the rotatable member over the contact pads; and an electric circuit generates the position feedback voltage in a first voltage range when the electric contact member contacts any of the insulating regions, in a second voltage range when the electric contact member contacts a home position contact pad and in a third voltage range when the electric contact member contacts any other contact pad. A control updates a position count whenever the output voltage changes from the first to another voltage range; and the count is corrected, if necessary, when the third voltage range is detected.

Abstract: An output of a power-on-reset (POR) circuit is coupled to another circuit which needs to have the logic states thereof reset during each time a power supply used to power same is switched on. The POR circuit includes a first input circuit for generating an output signal that tracks the power supply output voltage Vdd approximately a first predetermined threshold below Vdd, as Vdd ramps up and further includes a second input circuit which generates an output signal which tracks approximately a second predetermined threshold above a second fixed voltage level, e.g., ground. The POR circuit further includes a comparator which compares the output signals from the first and second input circuits and switches an output signal thereof from a first to a second logic state once the input circuit output signals cross each other. A buffer is typically coupled to the output of the comparator to limit loading on same so as not to affect the comparator switching point.

Abstract: A lamp monitor provides a sense resistor for each lamp circuit as a special sense terminal member with a series resistance and sense terminals connected to a circuit board in a lamp monitor module. A multiplexing arrangement allows selection of the circuit to be monitored. The monitor samples the voltage across the series resistance by first connecting a capacitor across the sense terminals to be charged to the voltage and then disconnecting the capacitor from the sense terminals and connecting it across the input of an amplifier. The voltage across the lamps is sensed to provide a ratiometric reference for the digitizing of the amplifier output in an analog to digital converter; and a digital computer corrects the input digital signal with a stored non-linear normalization factor relating current to voltage in the lamps.

Abstract: A motor driver interface (MDI) circuit includes fault detection apparatus effective to detect short circuits to the power supply in the switching transistors of an H-bridge reversible DC motor arrangement. A pair of timers distinguishes a true fault condition. The first timer is responsive to a continuous fault detection to define a first time period from its initiation; and a second timer is responsive to a continuous presence of a transistor conduction signal to define a second time period from its initiation. The apparatus stores a fault signal in response to the detection of the fault condition at the end of the first or second time periods with the first timer providing fault detection upon turn-on after the brief initial high transistor turn-on current and the second timer providing noise immunity.

Abstract: A fuel composition sensor for a fuel line carrying a mixture of two fuels provides a fuel composition signal VOUT to an engine control computer having a computer analog reference voltage ECM referenced to a computer ground EGD. The sensor has a sensor analog reference voltage VREF referenced to a sensor ground GND, which may differ from the computer ground EGD. An input isolation amplifier derives the sensor analog reference voltage VREF relative to GND ratiometrically from the computer analog reference voltage ECM referenced to EGD; and an output isolation amplifier derives the fuel composition signal VOUT referenced to EGD ratiometrically from the difference between a fuel composition responsive sensor signal VSIG and its minimum possible value, corresponding to a sensed fuel composition of only one of the fuels, relative to GND. The sensor may comprise a capacitive voltage divider and provide sensor voltage VSIG also having a maximum value corresponding to a sensed fuel composition of only the other fuel.

Abstract: A radiant wall oven with a heating chamber and hot air chamber separated by a radiant wall, an air heating chamber, supply and return ducts between the air heating chamber and hot air chamber and blower means for circulating hot air through the ducts is provided with a radiant wall temperature control comprising two cascaded closed loop controls. The first compares the radiant wall temperature with a first setpoint value to generate the difference as a second setpoint value for the second, which compares the temperature of the supply duct with the second setpoint value to control a heat source such as a burner. Under certain conditions, the air heating chamber is vented to atmosphere.

Abstract: A full vehicle suspension control for a wheeled vehicle includes a suspension actuator and an absolute accelerometer at each corner of the vehicle body. The actuators are controlled in response to vehicle body pitch and roll velocity signals which are derived from nominally vertical acceleration signals from the accelerometers by first deriving vehicle body pitch and roll acceleration signals and then integrating these signals into vehicle body roll and pitch velocity signals. The process of converting the body corner acceleration signals to pitch and roll acceleration signals reduces any non-vertical error of the signals before integration to reduce saturation of the integrator.

Abstract: A cylindrical heated airflow sensor for a constant temperature anenometer has a solid or tubular fused silica substrate with leads or terminals connected to each end. The sensor has a central heated section densely wound with resistive wire or covered with a resistive film, and an unheated section between the heated section and each terminal. Due to low heat conductivity of the substrate, the unheated section insulates the heated section from the terminals to improve the accuracy of the sensor at low airflow rates.

Abstract: An ignition timing system generates ignition timing pulses from a basic ignition timing, a current knock retard and an adaptive knock retard. It includes a plurality of memory cells in a one-dimensional lookup table referenced to predetermined engine speeds and determines the adpative knock retard by multiplying a number derived from the cells at the current engine speed by a load gain factor based on current engine load. It updates the cells on a fixed time period basis. When sufficient knock has occurred in a time period, an increase is applied to the one or more cells closest to the engine speed at which knock first occurred during the period, with the amount of increase based on the maximum current knock retard during the period. Thus, updating is frequent and may occur even in transient conditions; and the correction is focused on the engine speed at which knock was initiated so as to prevent such knock initiation in the future.

Abstract: A vehicle suspension uses actuators between sprung and unsprung masses, each actuator comprising a brushless dynamoelectric machine having a low inertia rotor engaged with a rotary/linear motion converter or conversion between dynamoelectric machine torque and linear actuator force. A control circuit for each machine applies current from an electric power source to the dynamoelectric machine in response to rotor position sensors and an input control signal to produce a desired actuator force providing motoring or generating action by the dynamoelectric machine. A common supply bus connecting the electric power source and dynamoelectric machines allows the dynamoelectric machines in generating mode to provide electric power to the dynamoelectric machines in motoring mode. Transient storage capacitors across the supply bus, current limiting from the supply bus to the storage battery, a dump resistance and dump switch responsive to battery voltage, and a supplementary alternator are also provided.

Abstract: In a fuel composition sensor in which a fast step voltage is applied to a capacitive voltage divider comprising a sensor capacitance and a reference capacitance in series, a padding capacitor is connected in parallel with the sensor capacitor to produce a more linear output across the full range of fuel composition. The value of the padding capacitor is sufficient to produce a capacitance ratio of the voltage divider substantially less than one and, in particular, less than two thirds.

Abstract: A motor driver interface (MDI) circuit for an H-bridge electric motor drive apparatus is responsive to an enable signal to turn off all switching transistors in a not enabled mode and turn on the upper bridge transistors in an enabled mode and includes large resistors, sufficiently large to prevent motor activation therethrough, from the motor terminals to the power supply terminals to establish a bias voltage in the not enabled mode. Fault detection apparatus compares the voltages at the motor terminals with a first reference voltage apparatus in the not enabled mode and a second reference voltage apparatus in the enabled mode in response to the enable signal.

Abstract: A full vehicle suspension control derives the vertical wheel and vertical body corner velocities at each corner of the vehicle body and derives therefrom a set of at least three body state velocity variables descriptive of vertical body motions and attitude. These body state velocity variables may be the body heave, roll and pitch velocities or a plurality of the vertical body corner velocities. The suspension control computes desired forces between each body corner and its corresponding wheel from a linear combination of the vertical wheel velocity of that wheel and the body state velocity variables and derives control signals from the desired forces and, in a semi-active system, the sign of demand power. The control signals are applied to vertical force actuators connected to exert vertical forces between the vehicle body and wheel at the vehicle body corners and capable of response at frequencies sufficient to control wheel as well as body vibrations in real time.