To accurately detect a zero gravity offset in an acceleration sensor. As an embodiment of the present invention, in the case where position information can be obtained from a GPS processing section, a velocity detecting unit performs an operation according to Expression (15), using real detected acceleration Gr that was actually obtained from the acceleration sensor, vehicle acceleration αP based on the position information, distance Dm, an amount of height change Dh based on pressure PR, and gravity acceleration g. Therefore, offset acceleration αo can be accurately calculated, and an acceleration detection signal can be converted into detected acceleration αG with high accuracy, based on a zero gravity offset value Vzgo by that the above offset acceleration αo was converted.

An apparatus and method for measuring the speed of a moving object is provided. A first acceleration along the moving direction of the moving object and a second acceleration along the lateral direction of the moving object are measured. A first angular speed along the lateral direction of the moving object and a second angular speed along the lower direction of the moving object are measured. The roll angle of the moving object using the first acceleration, the second angular speed, a previous speed of the moving object in the moving direction of the moving object, and a previous road inclination angle with respect to the moving direction of the moving object are calculated. A road inclination angle is calculated using the calculated roll angle, the first angular speed, and the second angular speed. A pure motion acceleration in the moving direction of the moving object is calculated using the calculated road inclination angle and the speed of the moving object is calculated using the pure motion acceleration of the moving object.

The application concerns a precise measurement of human body's movement, e.g. in the rehabilitation domain and/or physical training, physiotherapy and sport. The system is adapted to estimate any body part speed and displacement - and, therefore, motion - without any external reference, by means of inertial measurement. Acceleration data are stored and integrated to determine velocity and displacement. A modified acceleration function is derived to meet boundary conditions, e.g. initial and final speed must be zero.

By calculating the velocity from acceleration information that is obtained from an acceleration sensor that is located in a vehicle, this invention, determines whether or not the vehicle is stopped from only the acceleration information obtained from the acceleration sensor without using angle information for which there is a high possibility of error, so it is possible to improve the accuracy of the velocity value.

A vehicle stopped-judgment apparatus in a velocity-calculation apparatus comprising: an angle-calculation means 2 that calculates the road-surface angle from the acceleration component Ax that is parallel with the road surface and acceleration component Az that is perpendicular to the road surface and that are obtained from an acceleration sensor 1 installed in a vehicle; and a velocity-calculationmeans 3 that calculates the vehicle velocity using the road-surface angle and the acceleration component Ax obtained from the acceleration sensor 1; and that comprises: an unsteadiness-detection means 4 that detects the size of unsteadiness in the acceleration component Ax or Az obtained from the acceleration sensor 1; and a stopped-judgment means 5 that performs a comparison to determine whether or not the size of unsteadiness exceeds a certain set value, and when it does not exceed the set value, determines that said vehicle is stopped.

The present invention relates to measurement of a spatial velocity vector (v_x, v_y, v_z), i.a. in order to make determination of a geographical position possible. A proposed spatial velocity meter (200) includes an inertial measurement unit (210), a direction-sensing module (220) and a velocity processor (230). The inertial measurement unit (210) registers acceleration parameters (a) and angular velocity parameters (ω) in three dimensions. The direction-sensing module (220) registers a natural reference signal (R). The velocity processor (230) receives the acceleration parameters (a), the angular velocity parameters (ω) and the natural reference signal (R), and based thereon, generates the spatial velocity vector (v_x, v_y, v_z).

A velocity information acquisition section 21 acquires velocity information on the velocity of a vehicle and records this acquired information in a velocity information recording section 27. A state judgment section 23 judges start and stop states of the vehicle based on state information indicating the start and stop states of the vehicle that was acquired at a state information acquisition section 22. After this judgment, a minimum output velocity computing section 24 accurately computes, based on the velocity information recorded in velocity information recording section 27, a minimum output velocity in a period in which a vehicle velocity detection circuit 10 cannot detect velocity information. A movement condition computing section 25 can appropriately compute a relative movement distance or a relative movement velocity of the vehicle based on the state information acquired at state information acquisition section 22 and the minimum output velocity computed at minimum output velocity computing section 24.

Vorrichtung zur Erfassung eines Fortbewegungsvorganges, insbesondere für den Einsatz mit einem Fahrtschreiber oder Unfalldatenschreiber, mit einem im wesentlichen in der Fortbewegungsrichtung wirksamen Beschleunigungsgeber (5) und einer mit dessen Ausgang verbundenen ersten Auswertungs- und Berechnungseinheit (61 bis 64) zur Berechnung einer Vergleichsgröße zur Kontrolle der Signale eines Weg- oder Geschwindigkeitsgebers (3), dessen Signale zur Dokumentation desselben Fortbewegungsvorganges genutzt werden, anhand der Signale des Beschleunigungsgebers (5), wobei die erste Auswertungs- und Berechnungseinheit (61 bis 64) so ausgebildet ist, daß nicht die Beschleunigung in Fortbewegungsrichtung (a_W) repräsentierende Signalanteile (aO) im Signal des Beschleunigungsgebers (5) im wesentlichen eliminiert werden, indem dieses Signal in mindestens zwei kurzen, aufeinanderfolgenden Phasen des Fortbewegungsvorganges aufgenommen und einer vergleichenden Auswertung in diesen Phasen unterzogen wird.

Vorrichtung zur Erfassung eines Fortbewegungsvorganges, insbesondere für den Einsatz mit einem Fahrtschreiber oder Unfalldatenschreiber, mit einem im wesentlichen in der Fortbewegungsrichtung wirksamen Beschleunigungsgeber (5) und einer mit dessen Ausgang verbundenen ersten Auswertungs- und Berechnungseinheit (61 bis 64) zur Berechnung einer Vergleichsgröße zur Kontrolle der Signale eines Weg- oder Geschwindigkeitsgebers (3), dessen Signale zur Dokumentation desselben Fortbewegungsvorganges genutzt werden, anhand der Signale des Beschleunigungsgebers (5), wobei die erste Auswertungs- und Berechnungseinheit (61 bis 64) so ausgebildet ist, daß nicht die Beschleunigung in Fortbewegungsrichtung (a_W) repräsentierende Signalanteile (aO) im Signal des Beschleunigungsgebers (5) im wesentlichen eliminiert werden, indem dieses Signal in mindestens zwei kurzen, aufeinanderfolgenden Phasen des Fortbewegungsvorganges aufgenommen und einer vergleichenden Auswertung in diesen Phasen unterzogen wird.

Um die Auffahrgeschwindigkeit (v_a) eines schienengebundenen Wagens (1) auf ein Hindernis (2) zu ermitteln, wird zunächst der zeitliche Verlauf der Beschleunigung (b(t)) des Wagens erfaßt. Aus dem zeitlichen Verlauf der Beschleunigung (b(t)) wird durch zeitliche Integration die Auffahrgeschwindigkeit (v_a(t)) ermittelt, wobei als obere Integrationsgrenze der zuvor ermittelte Zeitpunkt (t_o) des negativen Beschleunigungsmaximums (b_max) herangezogen wird.

A method and apparatus (Fig. 3 and 4) for correcting a signal representing the integral of an input signal ACC. (Fig. 3) to eliminate the effects of errors in the input signal comprises deriving from one or more signals which bear functional relationship with the errors samples 15′ at 16, subjecting the samples to a correction algorithmic process at 18, integrating the process results at 19 and therewith correcting the input signal integral at 21. This differs from known arrangements, that demand a high sampling rate (at intervals 16) in accordance with the Nyquist sampling theorem and result in a large amount of sample data to be processed, by processing fewer samples 15′ taken at below the Nyquist rate at random or pseudorandom intervals or random ones of the intervals 16. Relatively few samples 15′ processed and integrated provide an acceptable quantitive estimate of the error in the integrated input signal. Preferably, and particularly to assist in low demands on computerised sample processing, the samples are spaced throughout the integration period by defining window intervals 25 and taking one or more samples 15′ randomly in each window interval.

The device (15) measures the number of revolutions completed by the shaft of a permanent magnet electric motor (M) in a period of time (t1) during which it is set in motion by the effect of its connection to a respective electrical supply source, essentially by means of calculation (2(5), 22, 23, 37) of the integral of the counter-electromotive force which the motor (M) develops in the aforementioned period of time.

Eine Einrichtung zur inertialen Geschwindigkeits- oder Beschleunigungs­messung weist eine Schaltungsanordnung zur Aufbereitung und -verarbei­tung von Meßsignalen auf, bei der diese Signale von Meßfühlern/Sensoren als Geber direkt in eine digitale Form gebracht und aufintegriert werden als Summen (S) von Produkten (P = X ^· V). Durch die A/D-Wandlung am Anfang der Schaltung fallen Fehlerquellen einer analogen Verarbeitungs­schaltung und deren Aufwand fort. Ein Rechner ist nicht notwendig.