Flextensional transducers and methods of using flextensional transducers. The transducer includes a piezoelectric element and may include at least one endcap coupled with the piezoelectric element. The endcap may have an outer portion formed of a first material and an inner portion formed of a second material having a greater flexibility than the first material. The endcap may be coupled with an annular piezoelectric element near either its outer circumference or its inner circumference. The piezoelectric element may be a planar disk or have a curved bowl-shape. The transducer may be coupled with, and at least partially restrained by, a support structure. The transducer may also be configured to permit light to pass therethrough.

A flexural ultrasonic transducer is disclosed. The ultrasonic transducer comprises a sealed case which includes a flexible membrane and which defines a sealed cavity. The sealed case has an inside and an outside. The ultrasonic transducer comprises an active element, for example, a piezoelectric element, inside the sealed case supported on the flexible membrane. The ultrasonic transducer includes a liquid in the cavity. The sealed case includes a resilient portion between the inside and outside of the case for allowing equalization of pressure between the inside and the outside of the case. The resilient portion may comprise resilient walls or a thin-wall section, the flexible membrane or the case.

An input device includes an operation panel member with an operation surface; a support member contacting a side face of the operation panel member to support the operation panel member, the side face being perpendicular to the operation surface of the operation panel member; and an actuator configured to vibrate the support member in a direction parallel to the operation surface. The support member contacts the operation panel member only at the side face, and the operation panel member vibrates in a direction parallel to the operation surface by transmission of a vibration of the support member from the side face to the operation panel member.

An air pulse generating element is disclosed. The air pulse generating element includes a membrane, actuated according to a driving signal; a plate, wherein a chamber is formed between the plate and the membrane; wherein during a first phase of the driving signal, the membrane is actuated to change a volume within the chamber to generate an air pulse; wherein during a second phase of the driving signal, the membrane is actuated such that a gap is temporarily formed; wherein the temporarily formed gap is configured to provide a temporary air shunt to accelerate an air balancing process between a first air pressure at a first side of the membrane and a second air pressure at a second side of the membrane.

An air pulse generating element is disclosed. The air pulse generating element includes a membrane, actuated according to a driving signal; a plate, wherein a chamber is formed between the plate and the membrane; wherein during a first phase of the driving signal, the membrane is actuated to change a volume within the chamber to generate an air pulse; wherein during a second phase of the driving signal, the membrane is actuated such that a gap is temporarily formed; wherein the temporarily formed gap is configured to provide a temporary air shunt to accelerate an air balancing process between a first air pressure at a first side of the membrane and a second air pressure at a second side of the membrane.

A sound producing device is disclosed. The sound producing device includes a first air pulse generating element, driven by a first driving signal comprising a first electrical pulse, the first electrical pulse comprises a first transition edge with a first transition polarity; and a second air pulse generating element, disposed adjacent to the first air pulse generating element, driven by a second driving signal comprising a second electrical pulse, the second electrical pulse comprises a second transition edge with a second transition polarity; wherein the first transition polarity is opposite to the second transition polarity; wherein the first transition edge generally coincides with the second transition edge; wherein air pulses generated by the first or the second air pulse generating element produce non-zero offset in terms of sound pressure level.

CMOS Ultrasonic Transducers and processes for making such devices are described. The processes may include forming cavities on a first wafer and bonding the first wafer to a second wafer. The second wafer may be processed to form a membrane for the cavities. Electrical access to the cavities may be provided.

CMOS Ultrasonic Transducers and processes for making such devices are described. The processes may include forming cavities on a first wafer and bonding the first wafer to a second wafer. The second wafer may be processed to form a membrane for the cavities. Electrical access to the cavities may be provided.

A vehicle computing system may implement techniques to dynamically adjust a volume and/or frequency of a sound emitted from a vehicle to warn an object (e.g., dynamic object) of a potential conflict with the vehicle. The techniques may include determining a baseline noise level and/or frequencies proximate to the object. The baseline noise level and/or frequencies may be determined based on an identification of one or more noise generating objects in the environment. The vehicle computing system may determine the volume and/or a frequency of the sound based in part on the baseline noise level and/or frequencies, an urgency of the warning, a probability of conflict between the vehicle and the object, a speed of the object, etc.

A vehicle computing system may implement techniques to dynamically adjust a volume and/or frequency of a sound emitted from a vehicle to warn an object (e.g., dynamic object) of a potential conflict with the vehicle. The techniques may include determining a baseline noise level and/or frequencies proximate to the object. The baseline noise level and/or frequencies may be determined based on an identification of one or more noise generating objects in the environment. The vehicle computing system may determine the volume and/or a frequency of the sound based in part on the baseline noise level and/or frequencies, an urgency of the warning, a probability of conflict between the vehicle and the object, a speed of the object, etc.