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[미국특허] Beacon proximity detection system for a vehicle 원문보기

IPC분류정보
국가/구분 United States(US) Patent 등록
국제특허분류(IPC7판)
  • G01C-003/00
  • B25J-005/00
출원번호 US-0864292 (1986-05-16)
발명자 / 주소
  • Maddox James F. (Arlington MA) Kadonoff Mark B. (Somerville MA) Berger Alan D. (Pittsburgh PA) Taivalkoski Amy L. (Salem NH) George
  • II Robert W. (Windham NH) Benayad-Cherif Faycal E. (Somerville MA
출원인 / 주소
  • Denning Mobil Robotics, Inc. (Woburn MA 02)
인용정보 피인용 횟수 : 137  인용 특허 : 0

초록

A proximity detection system for determining the distance between a vehicle and a navigation beacon by resolving the altitude angle between the beacon and the vehicle and determining the distance between them. The system then defines an optimum distance between the beacon and the vehicle and compare

대표청구항

A proximity detection system for determining the distance between a vehicle and a navigation beacon comprising: detector means, responsive to the beacon, for resolving the altitude angle between the beacon and the vehicle; means, responsive to said resolved altitude angle and to the height of the be

이 특허를 인용한 특허 (137) 인용/피인용 타임라인 분석

  1. Lissel Ernst,DEX ; Bahr Ulrich,DEX, Arrangement for determining the distance of objects.
  2. Gilbert, Jr., Duane L.; Williams, Marcus R.; Okerholm, Andrea M.; Kristant, Elaine H.; Longo, Sheila A.; Kee, Daniel E.; Strauss, Marc D., Autonomous coverage robot.
  3. Ozick, Daniel N.; Okerholm, Andrea M.; Mammen, Jeffrey W.; Halloran, Michael J.; Sandin, Paul E.; Won, Chikyung, Autonomous coverage robot navigation system.
  4. Ozick, Daniel N.; Okerholm, Andrea M.; Mammen, Jeffrey W.; Halloran, Michael J.; Sandin, Paul E.; Won, Chikyung, Autonomous coverage robot navigation system.
  5. Ozick, Daniel N.; Okerholm, Andrea M.; Mammen, Jeffrey W.; Halloran, Michael J.; Sandin, Paul E.; Won, Chikyung, Autonomous coverage robot navigation system.
  6. Gilbert, Jr., Duane L.; Williams, Marcus R.; Okerholm, Andrea M.; Kristant, Elaine H.; Longo, Sheila A.; Kee, Daniel E.; Strauss, Marc D., Autonomous coverage robot sensing.
  7. Hussey, Patrick Alan; Roy, Robert Paul; Neumann, Rogelio Manfred; Svendsen, Selma; Ozick, Daniel N.; Casey, Christopher M.; Kapoor, Deepak Ramesh; Campbell, Tony L.; Won, Chikyung; Morse, Christopher John; Burnett, Scott Thomas, Autonomous coverage robots.
  8. Jones, Joseph L.; Mack, Newton E.; Nugent, David M.; Sandin, Paul E., Autonomous floor cleaning robot.
  9. Jones, Joseph L.; Mack, Newton E.; Nugent, David M.; Sandin, Paul E., Autonomous floor-cleaning robot.
  10. Jones, Joseph L.; Mack, Newton E.; Nugent, David M.; Sandin, Paul E., Autonomous floor-cleaning robot.
  11. Jones, Joseph L.; Mack, Newton E.; Nugent, David M.; Sandin, Paul E., Autonomous floor-cleaning robot.
  12. Jones, Joseph L; Mack, Newton E; Nugent, David M; Sandin, Paul E, Autonomous floor-cleaning robot.
  13. Smith, Jennifer, Autonomous mobile robot.
  14. Chiappetta, Mark J.; Frankel, James Paul, Autonomous mobile robot system.
  15. Cohen, David A.; Ozick, Daniel N.; Vu, Clara; Lynch, James; Mass, Philip R., Autonomous robot auto-docking and energy management systems and methods.
  16. Cohen, David A.; Ozick, Daniel N.; Vu, Clara; Lynch, James; Mass, Philip R., Autonomous robot auto-docking and energy management systems and methods.
  17. Cohen, David A.; Ozick, Daniel; Vu, Clara; Lynch, James; Mass, Philip R., Autonomous robot auto-docking and energy management systems and methods.
  18. Cohen, David A.; Ozick, Daniel; Vu, Clara; Lynch, James; Mass, Philip R., Autonomous robot auto-docking and energy management systems and methods.
  19. Cohen, David A.; Ozick, Daniel; Vu, Clara; Lynch, James; Mass, Philip R., Autonomous robot auto-docking and energy management systems and methods.
  20. Morse, Christopher J.; Ziegler, Andrew; Gilbert, Duane; Jones, Andrew, Autonomous surface cleaning robot for dry cleaning.
  21. Morse, Christopher J.; Ziegler, Andrew; Gilbert, Duane; Jones, Andrew, Autonomous surface cleaning robot for dry cleaning.
  22. Morse, Christopher John; Ziegler, Andrew; Gilbert, Jr., Duane; Jones, Andrew, Autonomous surface cleaning robot for dry cleaning.
  23. Ziegler, Andrew; Morse, Christopher John; Gilbert, Jr., Duane L.; Jones, Andrew, Autonomous surface cleaning robot for dry cleaning.
  24. Ziegler, Andrew; Gilbert, Duane; Morse, Christopher J.; Pratt, Scott; Sandin, Paul; Dussault, Nancy; Jones, Andrew, Autonomous surface cleaning robot for wet and dry cleaning.
  25. Ziegler, Andrew; Gilbert, Duane; Morse, Christopher J.; Pratt, Scott; Sandin, Paul; Dussault, Nancy; Jones, Andrew, Autonomous surface cleaning robot for wet and dry cleaning.
  26. Ziegler, Andrew; Gilbert, Duane; Morse, Christopher John; Pratt, Scott; Sandin, Paul; Dussault, Nancy; Jones, Andrew, Autonomous surface cleaning robot for wet and dry cleaning.
  27. Ziegler, Andrew; Gilbert, Duane; Morse, Christopher John; Pratt, Scott; Sandin, Paul; Dussault, Nancy; Jones, Andrew, Autonomous surface cleaning robot for wet and dry cleaning.
  28. Ziegler, Andrew; Gilbert, Duane; Morse, Christopher John; Pratt, Scott; Sandin, Paul; Dussault, Nancy; Jones, Andrew, Autonomous surface cleaning robot for wet and dry cleaning.
  29. Ziegler, Andrew; Morse, Christopher John; Gilbert, Jr., Duane L.; Jones, Andrew; Pratt, Scott; Sandin, Paul E.; Dussault, Nancy, Autonomous surface cleaning robot for wet and dry cleaning.
  30. Konandreas, Stefanos; Ziegler, Andrew; Morse, Christopher John, Autonomous surface cleaning robot for wet cleaning.
  31. Konandreas, Stefanos; Ziegler, Andrew; Morse, Christopher John, Autonomous surface cleaning robot for wet cleaning.
  32. Konandreas, Stefanos; Ziegler, Andrew; Morse, Christopher John, Autonomous surface cleaning robot for wet cleaning.
  33. Pong Jr. William (Brookfield Center CT) Engelberger Joseph F. (Newtown CT) Evans ; Jr. John M. (Brookfield CT) Kazman William S. (Danbury CT), Autonomous vehicle for working on a surface and method of controlling same.
  34. Chiappetta, Mark J.; Frankel, James P., Celestial navigation system for an autonomous robot.
  35. Chiappetta, Mark J.; Frankel, James Paul, Celestial navigation system for an autonomous robot.
  36. Chiappetta, Mark J.; Frankel, James Paul, Celestial navigation system for an autonomous robot.
  37. Chiappetta, Mark J.; Frankel, James Paul, Celestial navigation system for an autonomous robot.
  38. Chiappetta, Mark J., Celestial navigation system for an autonomous vehicle.
  39. Chiappetta, Mark Joseph, Celestial navigation system for an autonomous vehicle.
  40. Kapoor, Deepak Ramesh; Dubrovsky, Zivthan A., Cleaning robot roller processing.
  41. Schnittman, Mark Steven; Dubrovsky, Zivthan A.; Mammen, Jeffrey W.; Solochek, Aaron, Compact autonomous coverage robot.
  42. Schnittman, Mark Steven; Dubrovsky, Zivthan A.; Mammen, Jeffrey W.; Solochek, Aaron, Compact autonomous coverage robot.
  43. Schnittman, Mark Steven; Dubrovsky, Zivthan A.; Mammen, Jeffrey W.; Solochek, Aaron, Compact autonomous coverage robot.
  44. Schnittman, Mark; Dubrovsky, Zivthan A.; Mammen, Jeffrey W.; Solochek, Aaron, Compact autonomous coverage robot.
  45. Onishi Masanori (Ise JPX), Control method for an unmanned vehicle (robot car).
  46. Svendsen, Selma; Ozick, Daniel N.; Casey, Christopher M.; Kapoor, Deepak Ramesh; Campbell, Tony L.; Won, Chikyung; Morse, Christopher John; Burnett, Scott Thomas, Coverage robot mobility.
  47. Svendsen, Selma; Ozick, Daniel N.; Casey, Christopher M.; Kapoor, Deepak Ramesh; Campbell, Tony L.; Won, Chikyung; Morse, Christopher John; Burnett, Scott Thomas, Coverage robot mobility.
  48. Svendsen, Selma; Ozick, Daniel N.; Casey, Christopher M.; Kapoor, Deepak Ramesh; Campbell, Tony L.; Won, Chikyung; Morse, Christopher John; Burnett, Scott Thomas, Coverage robot mobility.
  49. Svendsen, Selma; Ozick, Daniel N.; Casey, Christopher M.; Kapoor, Deepak Ramesh; Campbell, Tony L.; Won, Chikyung; Morse, Christopher John; Burnett, Scott Thomas, Coverage robot mobility.
  50. Schnittman, Mark Steven; Ozick, Daniel N.; Landry, Gregg W., Coverage robots and associated cleaning bins.
  51. Schnittman, Mark; Ozick, Daniel N.; Landry, Gregg W., Coverage robots and associated cleaning bins.
  52. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel, Debris sensor for cleaning apparatus.
  53. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N., Debris sensor for cleaning apparatus.
  54. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N., Debris sensor for cleaning apparatus.
  55. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N., Debris sensor for cleaning apparatus.
  56. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N., Debris sensor for cleaning apparatus.
  57. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N., Debris sensor for cleaning apparatus.
  58. Stephens,Scott Adam, Decoherence plate for use in a communications system.
  59. Ozick, Daniel N.; Gilbert, Jr., Duane L., Detecting robot stasis.
  60. Ozick, Daniel N.; Gilbert, Jr., Duane L., Detecting robot stasis.
  61. Merte, Rolf; Matthias, Björn; Kock, Sönke, Device and method for safeguarding a machine-controlled handling device.
  62. Carr,Gary A.; Diaz,Christian; Clouse,Arthur Lee, Integrated measurement device.
  63. Maddox James F. (Arlington MA) Kadonoff Mark B. (Somerville MA) George ; II Robert W. (Windham NH) Wendt Roger A. (Londonderry NH), Intrusion detection system.
  64. Gutmann, Steffen; Eade, Ethan; Fong, Philip; Munich, Mario, Localization by learning of wave-signal distributions.
  65. Tucker, Steven W.; Venard, Daniel C., Method and apparatus for extended use of cleaning fluid in a floor cleaning machine.
  66. Rench Quentin H. (Racine WI) Jacobs Stephen (Bayside CA), Method and apparatus for guiding a machine.
  67. Rekow,Andrew Karl Wilhelm; Stephens,Scott Adam, Method and system for determining relative position of mobile vehicles.
  68. Hunt,Kenneth Edward; Schmidt,Mark Alvin; Holm,David Roy; Zeitzew,Michael Alan; Stephens,Scott Adam, Method and system for determining the location of a vehicle.
  69. Schmidt, Mark Alvin; Hunt, Kenneth Edward; Holm, David Roy; Stephens, Scott Adam, Method and system for following a lead vehicle.
  70. Jones, Joseph L.; Mass, Philip R., Method and system for multi-mode coverage for an autonomous robot.
  71. Jones, Joseph L.; Mass, Philip R., Method and system for multi-mode coverage for an autonomous robot.
  72. Jones, Joseph L.; Mass, Philip R., Method and system for multi-mode coverage for an autonomous robot.
  73. Hunt,Kenneth Edward; Schmidt,Mark Alvin; Holm,David Roy; Stephens,Scott Adam, Method for configuring a local positioning system.
  74. DiBernado, Enrico; Pirjanian, Paolo, Methods and apparatus for position estimation using reflected light sources.
  75. DiBernardo, Enrico; Pirjanian, Paolo, Methods and apparatus for position estimation using reflected light sources.
  76. DiBernardo, Enrico; Pirjanian, Paolo, Methods and apparatus for position estimation using reflected light sources.
  77. DiBernardo, Enrico; Pirjanian, Paolo, Methods and apparatus for position estimation using reflected light sources.
  78. Stout, Michael S.; Brisson, Gabriel Francis; Di Bernardo, Enrico; Pirjanian, Paolo; Goel, Dhiraj; Case, James Philip; Dooley, Michael, Methods and systems for complete coverage of a surface by an autonomous robot.
  79. Stout, Michael S.; Brisson, Gabriel Francis; Di Bernardo, Enrico; Pirjanian, Paolo; Goel, Dhiraj; Case, James Philip; Dooley, Michael, Methods and systems for complete coverage of a surface by an autonomous robot.
  80. Stout, Michael S.; Brisson, Gabriel Francis; Di Bernardo, Enrico; Pirjanian, Paolo; Goel, Dhiraj; Case, James Philip; Dooley, Michael, Methods and systems for complete coverage of a surface by an autonomous robot.
  81. Hickerson, Kevin; Goncalves, Luis; Pirjanian, Paolo; Romanov, Nikolai, Methods and systems for obstacle detection using structured light.
  82. Hickerson, Kevin; Goncalves, Luis; Pirjanian, Paolo; Romanov, Nikolai, Methods and systems for obstacle detection using structured light.
  83. Wong, Cheuk Wah; Rauhut, Eben; Benson, Brian C.; Lydon, Peter J.; Rosenstein, Michael T.; Halloran, Michael; Shamlian, Steven V.; Won, Chikyung; Chiappetta, Mark; Kearns, Justin H.; Taka, Orjeta; Pack, Robert Todd; Farlow, Timothy S.; Vicenti, Jasper Fourways, Mobile robot.
  84. Won, Chikyung; Svendsen, Selma; Sandin, Paul E.; Burnett, Scott Thomas; Kapoor, Deepak Ramesh; Hickey, Stephen A.; Rizzari, Robert; Dubrovsky, Zivthan A. C., Modular robot.
  85. Ozick, Daniel N.; Okerholm, Andrea M.; Mammen, Jeffrey W.; Halloran, Michael J., Navigating autonomous coverage robots.
  86. Ozick, Daniel N.; Okerholm, Andrea M.; Mammen, Jeffrey W.; Halloran, Michael J.; Sandin, Paul E.; Won, Chikyung, Navigating autonomous coverage robots.
  87. Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  88. Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  89. Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  90. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N.; Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  91. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N.; Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  92. Landry, Gregg W.; Cohen, David A.; Ozick, Daniel N.; Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  93. Landry, Gregg W; Cohen, David A.; Ozick, Daniel N.; Chiappetta, Mark J.; Jones, Joseph L., Navigational control system for a robotic device.
  94. Mallinson, Dominic S, Object tracking with projected reference patterns.
  95. Casey, Christopher M.; Cross, Matthew; Ozick, Daniel N.; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  96. Casey, Christopher M.; Cross, Matthew; Ozick, Daniel N.; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  97. Casey, Christopher M.; Cross, Matthew; Ozick, Daniel N.; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  98. Casey, Christopher M.; Cross, Matthew; Ozick, Daniel N.; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  99. Casey, Christopher; Cross, Matthew; Ozick, Daniel; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  100. Casey, Christopher; Cross, Matthew; Ozick, Daniel; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  101. Casey, Christopher; Cross, Matthew; Ozick, Daniel; Jones, Joseph L., Obstacle following sensor scheme for a mobile robot.
  102. Weiman Carl F. R. (Westport CT) Evans ; Jr. John M. (Brookfield CT), One dimensional image visual system for a moving vehicle.
  103. Stephens,Scott Adam, Polarization sensitive synthetic aperture radar system and method for local positioning.
  104. Kamimura Kenji (Saitama JPX) Tsuzuki Sadachika (Saitama JPX), Position detector for moving vehicle.
  105. Kamimura Kenji (Saitama JPX) Tsuzuki Sadachika (Saitama JPX), Position-detecting and steering control system for moving vehicle.
  106. Stephens,Scott Adam, Positioning system with a sparse antenna array.
  107. Stephens,Scott Adam, Positioning system with co-polarized and cross-polarized mapping.
  108. Stephens,Scott Adam, Positioning system with intentional multi-path signal.
  109. Dubrovsky, Zivthan A.; Landry, Gregg W.; Halloran, Michael J.; Lynch, James, Remote control scheduler and method for autonomous robotic device.
  110. Dubrovsky, Zivthan; Landry, Gregg; Halloran, Michael John; Lynch, James Kenneth, Remote control scheduler and method for autonomous robotic device.
  111. Pudney Jack L. (Dandenong AUX) Baird Richard M. (East Malvern AUX), Remote controlled travel apparatus.
  112. Kramer Dale C. (R.R. #1 ; Weaver Road Port Colborne ; Ontario CAX L3K 5V3), Remotely-controlled vehicle.
  113. Won, Chikyung; Hickey, Stephen A.; Schnittman, Mark Steven; Dubrovsky, Zivthan A.; Svendsen, Selma; Lowry, Jed; Swett, David; Devlin, John, Removing debris from cleaning robots.
  114. Won, Chikyung; Hickey, Stephen A.; Schnittman, Mark Steven; Dubrovsky, Zivthan A.; Svendsen, Selma; Lowry, Jed; Swett, David; Devlin, John, Removing debris from cleaning robots.
  115. Won, Chikyung; Hickey, Stephen A.; Schnittman, Mark; Dubrovsky, Zivthan A.; Svendsen, Selma; Lowry, Jed; Swett, David; Devlin, John, Removing debris from cleaning robots.
  116. Jones, Joseph L.; Mass, Philip R., Robot confinement.
  117. Jones, Joseph L.; Mass, Philip R., Robot confinement.
  118. Jones, Joseph L.; Mass, Philip R., Robot confinement.
  119. Halloran, Michael J.; Mammen, Jeffrey W.; Campbell, Tony L.; Walker, Jason S.; Sandin, Paul E.; Billington, Jr., John N.; Ozick, Daniel N., Robot system.
  120. Halloran, Michael J.; Mammen, Jeffrey W.; Campbell, Tony L.; Walker, Jason S.; Sandin, Paul E.; Billington, Jr., John N.; Ozick, Daniel N., Robot system.
  121. Halloran, Michael J.; Mammen, Jeffrey W.; Campbell, Tony L.; Walker, Jason S.; Sandin, Paul E.; Billington, Jr., John N.; Ozick, Daniel N., Robot system.
  122. Halloran, Michael J.; Mammen, Jeffrey W.; Campbell, Tony L.; Walker, Jason S.; Sandin, Paul E.; Billington, Jr., John N.; Ozick, Daniel N., Robot system.
  123. Halloran, Michael J.; Mammen, Jeffrey W.; Campbell, Tony L.; Walker, Jason S.; Sandin, Paul E.; Billington, Jr., John N.; Ozick, Daniel N., Robot system.
  124. Dooley, Michael; Romanov, Nikolai; Pirjanian, Paolo; Chiu, Lihu; Di Bernardo, Enrico, Robotic game systems and methods.
  125. Stephens,Scott Adam, Synthetic aperture radar system and method for local positioning.
  126. Traster, Elden D., System and method for autonomous vehicle localization.
  127. Schmidt, Mark Alvin; Hunt, Kenneth Edward; Holm, David Roy; Stephens, Scott Adam, System and method for determining a position of a vehicle.
  128. Schmidt, Mark Alvin; Hunt, Kenneth Edward; Holm, David Roy; Stephens, Scott Adam, System and method for determining a position of a vehicle.
  129. Schmidt, Mark Alvin; Hunt, Kenneth Edward; Holm, David Roy; Stephens, Scott Adam, System and method for determining a position of a vehicle with compensation for noise or measurement error.
  130. Burnett, Scott Thomas; Maroon, Jared Randall, System and method for implementing force field deterrent for robot.
  131. Norman, David A.; Mimlitch, III, Robert H.; Adams, Paul S., System and method for managing and controlling robot competition.
  132. Romanov, Nikolai; Case, James Philip; Dooley, Michael, System for localization and obstacle detection using a common receiver.
  133. Norman, David A.; Mimlitch, III, Robert H.; Adams, Paul S., System, apparatus, and method for managing and controlling robot competitions.
  134. Hargrove Jeffrey B. ; Briggs John E. ; Wickham William G., Triangulation rangefinder and sight positioning system.
  135. Rentz,Mark Lindsay; Stephens,Scott Adam; Kaplan,Mark Phillip; Woo, deceased,Richard Kai Tuen, Two-way RF ranging system and method for local positioning.
  136. Blouin, Matthew, Vacuum brush.
  137. Yu, Chung-huang; Chien, Chih-wei, Walking assistance device with detection members.

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