A protective cover system for a motor vehicle includes a first roller, a first cover wound onto the first roller, a second roller and a second cover wound onto the second roller. The protective cover system also includes a control module for displacing the covers between stowed and deployed positions covering one or both of the motor vehicle bumper and an interior cargo floor of the motor vehicle.

A method for detecting a living being on a seat of a vehicle, further relating to a detection arrangement and to a vehicle. The method may include emitting electromagnetic waves at predetermined frequency or at a predetermined frequency band towards the seat by an electromagnetic radiator, receiving electromagnetic waves reflected on a surface by a sensor, detecting an object on the seat from a transit time of the emitted and the reflected electromagnetic waves between the radiator, the surface and the sensor by a detection device, detecting movements of the object from the reflected electromagnetic waves by the detection device if an object has been detected, determining from the detected movements of the object whether the detected object is a living being, and outputting a detection signal by way of the detection device if it has been determined that the detected object is a living being.

A method for detecting a living being on a seat of a vehicle, further relating to a detection arrangement and to a vehicle. The method may include emitting electromagnetic waves at predetermined frequency or at a predetermined frequency band towards the seat by an electromagnetic radiator, receiving electromagnetic waves reflected on a surface by a sensor, detecting an object on the seat from a transit time of the emitted and the reflected electromagnetic waves between the radiator, the surface and the sensor by a detection device, detecting movements of the object from the reflected electromagnetic waves by the detection device if an object has been detected, determining from the detected movements of the object whether the detected object is a living being, and outputting a detection signal by way of the detection device if it has been determined that the detected object is a living being.

An object detector includes: a triangulation calculation unit that performs triangulation calculation for detecting a location of an object based on first distance information calculated based on direct waves in which transmitted waves transmitted from a first transmission and reception unit are reflected by an object and received by the first transmission and reception unit, and second distance information calculated based on indirect waves in which transmitted waves transmitted from a second transmission and reception unit arranged in a location different from the first transmission and reception unit are reflected by an object and received by the first transmission and reception unit; and a prohibition processing unit that prohibits triangulation calculation when a difference between first velocity information indicating a velocity of an object calculated based on the direct waves and second velocity information indicating a velocity of an object calculated based on the indirect waves exceeds a predetermined range.

An object detector includes: a triangulation calculation unit that performs triangulation calculation for detecting a location of an object based on first distance information calculated based on direct waves in which transmitted waves transmitted from a first transmission and reception unit are reflected by an object and received by the first transmission and reception unit, and second distance information calculated based on indirect waves in which transmitted waves transmitted from a second transmission and reception unit arranged in a location different from the first transmission and reception unit are reflected by an object and received by the first transmission and reception unit; and a prohibition processing unit that prohibits triangulation calculation when a difference between first velocity information indicating a velocity of an object calculated based on the direct waves and second velocity information indicating a velocity of an object calculated based on the indirect waves exceeds a predetermined range.

The adjustable voltage regulator under control of a microcontroller applies controlled amplitude voltage in the range of 5 to 9VDC to the sensor transmitter to adjust the output amplitude of the transmitter. The adjustable amplitude transmitter allows an occupancy sensor to have its total output energy adjusted to reduce environmental noise-induced false triggering and to conform to the area to be covered. Lowering the total ultrasonic energy in the monitored space lowers the sensitivity of the receiver to inappropriate activations. Lowering the input power to the transmitter also lowers the total internal system noise and provides an improved signal to noise ratio in the receiver.

The adjustable voltage regulator under control of a microcontroller applies controlled amplitude voltage in the range of 5 to 9VDC to the sensor transmitter to adjust the output amplitude of the transmitter. The adjustable amplitude transmitter allows an occupancy sensor to have its total output energy adjusted to reduce environmental noise-induced false triggering and to conform to the area to be covered. Lowering the total ultrasonic energy in the monitored space lowers the sensitivity of the receiver to inappropriate activations. Lowering the input power to the transmitter also lowers the total internal system noise and provides an improved signal to noise ratio in the receiver.

An acoustic, preferably ultrasonic, wave emission and/or reception device, including a wave emitter configured to transmit waves at an emission frequency, and a receiver of preferably ultrasonic waves, separate from the emitter, having a resonance frequency, and configured to receive waves generated by the emitter and including direct waves and reflected waves, wherein the device includes a resonance frequency modulator of the receiver and a control unit configured to control the resonance frequency modulator during a predetermined time period, so as to reduce the sensitivity of the receiver during the predetermined time period by moving the resonance frequency of the receiver away from the emission frequency of the emitter. The acoustic device relates to the field of ultrasonic sensors, particularly PMUTs or CMUTs, having a high quality factor.

A thermal excitation acoustic-wave-generating device includes a first heating element, a substrate that includes a main surface along which the first heating element is disposed, and a facing body that faces the substrate with the first heating element interposed therebetween. The substrate and the facing body define a path for an acoustic wave. A length of the path is close to a whole number multiple of ¼ of a wavelength of the acoustic wave.

Techniques for presence-detection devices to detect movement of a person in an environment by emitting ultrasonic signals using a loudspeaker that is concurrently outputting audible sound. To detect movement by the person, the devices characterize the change in the frequency, or the Doppler shift, of the reflections of the ultrasonic signals off the person caused by the movement of the person. However, when a loudspeaker plays audible sound while emitting the ultrasonic signal, audio signals generated by microphones of the devices include distortions caused by the loudspeaker. These distortions can be interpreted by the presence-detection devices as indicating movement of a person when there is no movement, or as indicating lack of movement when a user is moving. The techniques include processing audio signals to remove distortions to more accurately identify changes in the frequency of the reflections of the ultrasonic signals caused by the movement of the person.