One aspect of the technology involves a system for measuring the rotational position of a rotating shaft, including a field source configured to generate a measurable field, a sensor configured to measure the generated field, and a target that is configured to modify the generated field as measured by the sensor to have a shape with (a) at least one measurable feature for a zero reference point, and (b) a shape that varies throughout one or more angles such that a rotational position of the shaft is determined with a selected angular accuracy. There is also a device that receives a query for the rotational position of the shaft a device that responds to the query. Another aspect involves generating multi-frequency vibrations with a single linear resonant actuator (LRA). This LRA can exhibit a beat pattern in response to being driven by the sum of two different sinusoidal functions.

One aspect of the technology involves a system for measuring the rotational position of a rotating shaft, including a field source configured to generate a measurable field, a sensor configured to measure the generated field, and a target that is configured to modify the generated field as measured by the sensor to have a shape with (a) at least one measurable feature for a zero reference point, and (b) a shape that varies throughout one or more angles such that a rotational position of the shaft is determined with a selected angular accuracy. There is also a device that receives a query for the rotational position of the shaft a device that responds to the query. Another aspect involves generating multi-frequency vibrations with a single linear resonant actuator (LRA). This LRA can exhibit a beat pattern in response to being driven by the sum of two different sinusoidal functions.

A food spoilage determination device is disclosed. The device includes a processor, an input device, an output device, and a memory. The device also includes a proximity sensor configured to determine a distance to a target and to communicate a distance signal to the processor, one or more environment sensors configured to determine one or more aspects of an environment of the target and to communicate one or more environment aspect signals to the processor, and one or more chemical sensors configured to determine one or more concentrations of one or more chemicals in the environment of the target and to communicate one or more chemical concentration signals to the processor. The processor is configured to determine food spoilage of the target based on the distance signal, the environment aspect signals, and the chemical concentration signals.

A food spoilage determination device is disclosed. The device includes a processor, an input device, an output device, and a memory. The device also includes a proximity sensor configured to determine a distance to a target and to communicate a distance signal to the processor, one or more environment sensors configured to determine one or more aspects of an environment of the target and to communicate one or more environment aspect signals to the processor, and one or more chemical sensors configured to determine one or more concentrations of one or more chemicals in the environment of the target and to communicate one or more chemical concentration signals to the processor. The processor is configured to determine food spoilage of the target based on the distance signal, the environment aspect signals, and the chemical concentration signals.

Tools used to detect underlying structures, such as behind the surface of a wall, can include a first sensor, such as an electromagnetic sensor, configured to generate data indicative of the location of the underlying structure. Tools can include an indicator that provides an indication to a user based on the data. Tools can additionally or alternatively include an infrared imaging device for generating infrared image data indicative of the heat pattern of a scene. A display can display the generated infrared image data. Underlying structures may be visible in the heat pattern of the scene. The tool can indicate the presence of an underlying structure feature to an operator via one or both of the display and the indicator.

Tools used to detect underlying structures, such as behind the surface of a wall, can include a first sensor, such as an electromagnetic sensor, configured to generate data indicative of the location of the underlying structure. Tools can include an indicator that provides an indication to a user based on the data. Tools can additionally or alternatively include an infrared imaging device for generating infrared image data indicative of the heat pattern of a scene. A display can display the generated infrared image data. Underlying structures may be visible in the heat pattern of the scene. The tool can indicate the presence of an underlying structure feature to an operator via one or both of the display and the indicator.

A person support apparatus includes one or more thermal image sensors whose outputs are analyzed to perform one or more functions. Such functions include automatically turning on a brake, automatically turning on one or more lights, detecting when a patient associated with the person support apparatus has fallen, enabling a propulsion system of the patient support apparatus to be used, automatically controlling one or more environmental controls, and/or automatically arming an exit detection system after entry of a patient onto the person support apparatus. Multiple thermal images may be generated from multiple sensors to generate stereoscopic thermal images of portions of the person support apparatus and its surroundings.

A person support apparatus includes one or more thermal image sensors whose outputs are analyzed to perform one or more functions. Such functions include automatically turning on a brake, automatically turning on one or more lights, detecting when a patient associated with the person support apparatus has fallen, enabling a propulsion system of the patient support apparatus to be used, automatically controlling one or more environmental controls, and/or automatically arming an exit detection system after entry of a patient onto the person support apparatus. Multiple thermal images may be generated from multiple sensors to generate stereoscopic thermal images of portions of the person support apparatus and its surroundings.

A color wheel rotation speed detecting module is disclosed and includes a color wheel, a motor, a rotation speed detector and a processor. The color wheel includes a first segment and at least one second segment. The motor drives the color wheel to rotate. The rotation speed detector includes an emitter and a receiver. The emitter outputs a light signal to the first segment or the second segment of the color wheel when the color wheel is rotated. When the receiver receives the light signal reflected from the second segment, the receiver outputs a detecting signal correspondingly. When the light signal passes through the first segment and the receiver fails to receive the light signal, the receiver interrupts the output of the detecting signal. The processor receives the detecting signal from the receiver, and obtains the rotating speed of the color wheel according to the detecting signal varied with time.

A sensor system is configured to control one or more operational functions of one or more components. The sensor system includes one or more protuberances, a first channel defined by the one or more protuberances, a second channel defined by the one or more protuberances, and one or more sensing devices configured to detect one or more actions of an object in relation to one or more of the one or more protuberances, the first channel, or the second channel. The one or more actions of the object are associated with the one or more operational functions of the one or more components.