Title:
NAVIGATION DEVICE
Document Type and Number:
Japanese Patent JP3857286
Kind Code:
B
Abstract:
PROBLEM TO BE SOLVED: To calculate a speed and a distance with high accuracy, even when integration errors and accumulation errors are made in calculation of velocity data and a movement distance, and when a drift is generated in the output value of an acceleration sensor.
SOLUTION: This navigation device is provided with a sensor 1 for detecting acceleration in the longitudinal direction of a vehicle and sensors 2 and 3 for outputting predetermined data, corresponding to the positional/directional change of the vehicle. Actual acceleration is found by performing predetermined computing on the acceleration data; first speed data matching a vehicle speed is outputted, based on output data from the sensors 2 and 3; positional/directional change quantity per unit time of the vehicle is found, based on the actual acceleration or the output data from the sensors 2 and 3; a movement distance of the vehicle is calculated, based on change quantity data, second speed data matching the vehicle speed are found based on the actual acceleration; and multiplication of the the second speed data by a gain is carried out, while the gain value is updated based on the first speed data and the second speed data, when a vehicle shifts in a uniform velocity movement condition.
Inventors:
Baba, Toshiji
Sato, Hiroshi
Sato, Hiroshi
Application Number:
JP2004000341059
Publication Date:
September 22, 2006
Filing Date:
November 25, 2004
Export Citation:
Assignee:
PIONEER ELECTRONIC CORP
International Classes:
G01C21/00; G01C21/00; (IPC1-7): G01C21/00