An electronic speed detection system is provided. The electronic speed detection system includes an accelerometer coupled to a moving object and a hybrid altimeter, which includes a first pressure sensor coupled to the moving object and a second pressure sensor. The electronic speed detection system also includes a controller comprising a memory and a processor. The memory storing computer program instructions executable by the processor to cause the electronic speed detection system to determine a normalized position based on first inputs received from the hybrid altimeter, or determine a corrected velocity position based on a second input received from the accelerometer and the normalized position.

In a measurement unit, a primary acceleration sensor is fixed at the center of gravity of a flying object or at a position within a certain error range from the center of gravity. A secondary acceleration sensor is fixed inside the flying object so as to be spaced from the center of gravity of the flying object. In a measurement apparatus, an acquirer acquires a primary acceleration measured by the primary acceleration sensor during flight of the flying object and a secondary acceleration measured by the secondary acceleration sensor during the flight of the flying object. An estimator estimates a spin rate per unit time of the flying object from the acquired primary acceleration and the acquired secondary acceleration using maximum likelihood estimation.

Embodiments relate to determining a speed of a multidimensional motion of an athlete in a global coordinate system based on multidimensional acceleration data from a multidimensional accelerometer placed at a movable limb of the athlete, the movable limb being at least one of translatory and rotatable, and the movable limb defining a local coordinate system. Based on the multidimensional acceleration data, at least one correction quantity may be determined taking into account a rotation of the local coordinate system relative to the global coordinate system during the multidimensional motion. The speed of the multidimensional motion may be determined based on an integration of the multidimensional acceleration data and in consideration of the at least one correction quantity.

Embodiments relate to determining a speed of a multidimensional motion of an athlete in a global coordinate system based on multidimensional acceleration data from a multidimensional accelerometer placed at a movable limb of the athlete, the movable limb being at least one of translatory and rotatable, and the movable limb defining a local coordinate system. Based on the multidimensional acceleration data, at least one correction quantity may be determined taking into account a rotation of the local coordinate system relative to the global coordinate system during the multidimensional motion. The speed of the multidimensional motion may be determined based on an integration of the multidimensional acceleration data and in consideration of the at least one correction quantity.

Swimming goggles are developed to allow a swimmer to see the end of the pool without moving their head while swimming in backstroke. Using a light reflector, a swimmer can see through a backstroke viewing window, allowing them to see along the direction that they are moving when swimming backstroke. Using a motion sensor and electric control circuits, a swimming goggle can provide optimum views for the swimmer wearing the swimming goggle. Using a sound speaker, a swimming goggle can play music and provide voice reports to the swimmer. Flow meters and inclinometers can be used provide measurements with better accuracy. The electronic controller for a swimming goggle can either be embedded as part of a swimming goggle, or can be detachable to support more than one swimming goggle. Besides swimming goggles, the electronic devices also can be attached onto athletic headgears such as eye goggles, sweat bands, hats, or helmets.

Swimming goggles are developed to allow a swimmer to see the end of the pool without moving their head while swimming in backstroke. Using a light reflector, a swimmer can see through a backstroke viewing window, allowing them to see along the direction that they are moving when swimming backstroke. Using a motion sensor and electric control circuits, a swimming goggle can provide optimum views for the swimmer wearing the swimming goggle. Using a sound speaker, a swimming goggle can play music and provide voice reports to the swimmer. Flow meters and inclinometers can be used provide measurements with better accuracy. The electronic controller for a swimming goggle can either be embedded as part of a swimming goggle, or can be detachable to support more than one swimming goggle. Besides swimming goggles, the electronic devices also can be attached onto athletic headgears such as eye goggles, sweat bands, hats, or helmets.

An estimation device includes a detecting unit that detects acceleration; an acquiring unit that acquires a feature value that is based on the acceleration; and an estimation unit that estimates a speed based on a limit value of the feature value.

An estimation device includes a detecting unit that detects acceleration; an acquiring unit that acquires a feature value that is based on the acceleration; and an estimation unit that estimates a speed based on a limit value of the feature value.

Method and apparatus are disclosed for GNSS statistical speed calibration An example vehicle includes a wheel, a speed sensor for determining a first vehicle speed, an inertial sensor, and a processor. The processor may be configured for determining a second vehicle speed based on information from the inertial sensor and information from a satellite based system, determining that a difference between the first and second vehicle speeds is statistically significant, and responsively adjusting a value of the radius of the wheel.

Wearable electronic devices that are designed to be worn on the head of a user while the user is swimming can determine swimming strokes and swimming performances of the user using motion sensors. Using a sound speaker, the wearable electronic device can play music and provide audio feedback to the swimmer. By comparing the swimming performance of the swimmer wearing the device with previously recorded swimming data, the wearable electronic device can provide audio comparison results to the swimmer while the swimmer is swimming in water. The wearable electronic device can also support similar functions for other sports and physical activities.