History and
Original Ideas
of Omnidirectional Vision Sensors
The history
[1970]
The original
idea of the omnidirectional vision sensor has been
initially proposed by Rees [1]. In the US
patent [1], Rees proposed to use a hyperboloidal
mirror to capture the omnidirectional image which
can be transformed to normal perspective images.
[1990]
Yagi and Kawato
[2] made an omnidirectional vision sensor using a
conic mirror.
[1991]
Hong and
others [3] made an omnidirectional vision sensor
using a spherical mirror.
[1993]
Yamazawa and others [4] made again
an omnidirectional vision sensor using a hyperboloidal mirror.
[1997]
Nayar and Baker [5] developed an
ideal omnidirectional vision sensor using a
parabola mirror and a telecentric lens.
The omnidirectional vision sensor using a hyperboloidal
mirror can generate an image taken from a single view point in combination
with a standard perspective camera.
However, it
has a demerit that one of the focal points of the hyperboloidal
mirror has to be set on the camera center.
This demerit
makes it difficult to design the omnidirectional
sensors. On the other hand, the imaging system proposed by Nayar and Baker does not have such a demerit.
Further, the
imaging system is superior in acquisition of non-blurred images and it can
eliminate internal reflection with cylindrical or spherical glass which
supports the mirror since it uses a telecentric
lens.
[1997]
The imaging
system developed by Nayar and Baker is ideal but it
is difficult to make it small since the system uses a telecentric
lens. Ishiguro and others [6, 7] developed low cost and compact omnidirectional sensors using spherical and hyperboloidal mirrors with two ideas as follows.
Our ideas
In order to make low cost and compact omnidirectional
sensors, we have eveloped the following two
techniques:
- Eliminating
internal reflection of the cylindrical glass with a black center needle.
With this imaging method, we could use precise cylindrical glass to
support the mirror and as the result, we could acquire precise omnidirectional images. We are applying for a
Japanese Patent on this idea.
- Making
the mirror from metal. By using metal, we can easily make any kinds of
shapes of the mirror. We have developed original methods to shave metal
and coating it for making precise mirrors.
References
- D.
W. Rees, Panoramic television viewing system, United States Patent No.
3, 505, 465, Apr. 1970.
- Y. Yagi and S. Kawato,
Panoramic scene analysis with conic projection, Proc. Int. Conf. Robots
and Systems, 1990.
- J.
Hong, and others, Image-based homing, Proc. Int. Conf. Robotics and
Automation, 1991.
- K. Yamazawa, Y. Yagi and M. Yachida, Omnidirectional
imaging with hyperboloidal projection, Proc.
Int. Conf. Robots and Systems, 1993.
- S.
K. Nayar and S. Baker, Catadioptiric
image formation, Proc. 1997 DARPA Image Understanding Workshop, pp.
1431-1437, 1997.
- H.
Ishiguro, T. Sogo and T. Ishida, Human behavior recognition by a
distributed vision system, Proc. DiCoMo
Workshop, pp.615-620, 1997. (in Japanese)
- H.
Ishiguro, Compact omnidirectional sensors and
their applications, M & E, Kougyou-Chosakai,
March 1998. (in Japanese)
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