Locus correcting method, locus correcting apparatus, and mobile object equipment

• US 9,182,235 B2
• Filed: 05/20/2011
• Issued: 11/10/2015
• Est. Priority Date: 05/20/2011
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Hara, Yoshitaka, Oshima, Akira, Yamamoto, Kenjiro, Hosoda, Yuji
• Primary Examiner(s): Shaawat, Mussa A
• Application Number:
  US14/118,899
• Publication Number:
  US 20140088863A1
• Time in Patent Office: 1,635 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G01C 21/005 with correlation of navigation data from several sources, e.g. map or contour matching G01C21/30 takes precedence
• CPC Class Codes: G01C 21/30 Map- or contour-matching

Abstract

Calculating a highly accurate locus is a goal. An administrative part (20) for correcting a traveling locus of a mobile object (V) is characterized by including an evaluation function generating unit (21) that sets a plurality of nodes on locus data of the mobile object (V) acquired by a wheel rotation quantity measuring unit (16), correlates position data of the mobile object (V) acquired by the wheel rotation quantity measuring unit (16) to the nodes and correlates position data of the mobile object (V) acquired by other units of measurement means than the wheel rotation quantity measuring unit to the nodes, represents positions at which the nodes may occur by probability, represents positions at which position data correlated to the nodes may occur by probability, and calculates an evaluation function including the nodes and the position data as variables, based on each probability; and a locus optimization calculation unit (22) that calculates a locus on which each node occurs with largest probability, based on the evaluation function.

Claims

1. A computer-implemented locus correcting method for correcting a traveling locus of a mobile object by a locus correcting apparatus, the locus correcting apparatus comprising a plurality of measurement means, wherein

the locus correcting apparatus performs:

setting, using a processor, a plurality of nodes on locus data of the mobile object acquired by one unit of measurement means;

correlating, using the processor, position data of the mobile object acquired by the one unit of measurement means to the nodes and correlating, using at least one node of the plurality of nodes as a reference value, position data of the mobile object acquired by other units of measurement means than the one unit of measurement means to the nodes;

representing, using the processor, positions at which the nodes may occur by probability;

representing, using the processor, positions at which position data correlated to the nodes may occur by probability;

calculating, using the processor, an evaluation function including the nodes and the position data as variables, based on each probability; and

calculating, using the processor, a locus on which each node occurs with largest probability, based on the evaluation function.

2. The computer-implemented locus correcting method according to claim 1 characterized in that:

the probability is represented by a probability density function;

the evaluation function is a likelihood function; and

the locus correcting apparatus calculates a locus on which the each node occurs with largest probability according to a maximum likelihood estimation method.

3. The computer-implemented locus correcting method according to claim 1 characterized in that:

the locus correcting apparatus makes a map by pasting shape data of structures around the calculated locus.

4. A computer-implemented locus correcting apparatus for correcting a traveling locus of a mobile object, the locus correcting apparatus comprising:

a plurality of measurement means;

an evaluation function generating unit; and

a locus optimization calculation unit, wherein the evaluation function generation unit that performs;

setting a plurality of nodes on locus data of the mobile object acquired by one unit of the measurement means,

correlating position data of the mobile object acquired by the one unit of the measurement means to the nodes and correlating, using at least one node of the plurality of nodes as a reference value, position data of the mobile object acquired by other units of the measurement means than the one unit of the measurement means to the nodes,

representing positions at which the nodes may occur by probability,

representing positions at which position data correlated to the nodes may occur by probability, and

calculating an evaluation function including the nodes and the position data as variables, based on each probability; and

the locus optimization calculation unit that calculates a locus on which each node occurs with largest probability, based on the evaluation function.

5. A mobile object equipment characterized by being equipped with the computer-implemented locus correcting apparatus according to claim 4.