$\require{mediawiki-texvc}$

연합인증

연합인증 가입 기관의 연구자들은 소속기관의 인증정보(ID와 암호)를 이용해 다른 대학, 연구기관, 서비스 공급자의 다양한 온라인 자원과 연구 데이터를 이용할 수 있습니다.

이는 여행자가 자국에서 발행 받은 여권으로 세계 각국을 자유롭게 여행할 수 있는 것과 같습니다.

연합인증으로 이용이 가능한 서비스는 NTIS, DataON, Edison, Kafe, Webinar 등이 있습니다.

한번의 인증절차만으로 연합인증 가입 서비스에 추가 로그인 없이 이용이 가능합니다.

다만, 연합인증을 위해서는 최초 1회만 인증 절차가 필요합니다. (회원이 아닐 경우 회원 가입이 필요합니다.)

연합인증 절차는 다음과 같습니다.

최초이용시에는
ScienceON에 로그인 → 연합인증 서비스 접속 → 로그인 (본인 확인 또는 회원가입) → 서비스 이용

그 이후에는
ScienceON 로그인 → 연합인증 서비스 접속 → 서비스 이용

연합인증을 활용하시면 KISTI가 제공하는 다양한 서비스를 편리하게 이용하실 수 있습니다.

Articulating arm for positioning a tool at a location 원문보기

IPC분류정보
국가/구분 United States(US) Patent 등록
국제특허분류(IPC7판)
  • G05F-019/04
출원번호 US-0370190 (2003-02-19)
우선권정보 GB-0020461.0(2000-08-18)
발명자 / 주소
  • Buckingham,Robert Oliver
  • Graham,Andrew Crispin
출원인 / 주소
  • Oliver Crispin Robotics Limited
대리인 / 주소
    St. Onge Steward Johnston & Reens LLC
인용정보 피인용 횟수 : 129  인용 특허 : 17

초록

A robotic arm device capable of accessing machinery and equipment, which is otherwise difficult access for maintenance and repair is provided. An apparatus comprising a support arm with a plurality of longitudinal segments each capable of movement one with respect to the other to define a serpentine

대표청구항

The invention claimed is: 1. A robot arm apparatus comprising: a plurality of longitudinal segments arranged sequentially along the arm, each segment movable with respect to the others to define a serpentine path or shape, in which; each segment comprises a plurality of links arranged sequentially

이 특허에 인용된 특허 (17)

  1. Borenstein, Johann, Apparatus for obstacle traversion.
  2. Borenstein, Johann; Long, Geoffrey A., Apparatus for obstacle traversion.
  3. Uratani, Takafumi, Arm operation mechanism and industrial robot incorporating the same.
  4. Brog.ang.rdh, Torgny, Device for relative displacement of two elements.
  5. Shen, Wei-Min; Salemi, Behnam; Will, Peter, Distributed control and coordination of autonomous agents in a dynamic, reconfigurable system.
  6. Wilcox, Brian, Gas pipe explorer robot.
  7. Brunman Barbro (Vasters SEX) Persson Stig (Vasters SEX), Industrial robot.
  8. Forslund Karl-Erik,SEX, Industrial robot.
  9. Jannborg Bjrn (Vsters SEX), Industrial robot having a detachable electrical connection between housing on robot arm and tool holder.
  10. Ove Kullborg SE; Einar Myklebust SE, Industrial robot having convection cooled frequency converters.
  11. Borenstein, Johann; Granosik, Grzegorz, Integrated, proportionally controlled, and naturally compliant universal joint actuator with controllable stiffness.
  12. Hvittfeldt, Hakan; Larsson, Jan; Mikaelsson, Pierre; Persson, Fredik, Manipulator.
  13. Salisbury, Jr., J. Kenneth; Madhani, Akhil J.; Guthart, Gary S.; Niemeyer, Gunter D.; Duval, Eugene F., Master having redundant degrees of freedom.
  14. Inoue Kiyoshi (Tokyo JPX), Robot.
  15. Tesar Delbert (Austin TX), Robot and robot actuator module therefor.
  16. Dahlquist Hkan (Vsters SEX), Robot wrist.
  17. Hosono Saburo (Hachioji JPX), Structure for preventing the breakage of end portions of a protective covering for the adjustable bend section of an end.

이 특허를 인용한 특허 (129)

  1. Gutschow, Matthew Stephen; Batzinger, Thomas James; Thompson, Christopher Edward, Actuatable visual inspection device.
  2. Shelton, IV, Frederick E.; Beckman, Andrew T.; Hess, Christopher J.; Morgan, Jerome R., Adaptable surgical instrument handle.
  3. Jacobsen, Stephen C.; Smith, Fraser M.; Olivier, Marc X., Amphibious robotic crawler.
  4. Spivey, James T.; Ortiz, Mark S.; Shelton, IV, Frederick E., Articulatable surgical device.
  5. Kerr, Wendy A.; Lytle, IV, Thomas W.; Overmyer, Mark D.; Swensgard, Brett E.; Leimbach, Richard L.; Sackett, Kevin D., Articulatable surgical instrument comprising a firing drive.
  6. Jaworek, Gary S.; Koch, Jr., Robert L.; Auld, Michael D.; Kimsey, John S.; Baber, Daniel L.; Leimbach, Richard L.; Ulrich, Daniel J., Articulatable surgical instruments with conductive pathways for signal communication.
  7. Zubiate, Brett; Choset, Howard; Degani, Amir; Skaff, Sarjoun, Articulated device with visualization system.
  8. Zubiate, Brett; Choset, Howard; Degani, Amir; Skaff, Sarjoun, Articulated device with visualization system.
  9. Shelton, IV, Frederick E.; Morgan, Jerome R., Automated end effector component reloading system for use with a robotic system.
  10. Shelton, IV, Frederick E.; Morgan, Jerome R., Automated end effector component reloading system for use with a robotic system.
  11. Shelton, IV, Frederick E.; Morgan, Jerome R., Automated reloading devices for replacing used end effectors on robotic surgical systems.
  12. Shelton, IV, Frederick E.; Morgan, Jerome R.; Yates, David C.; Baxter, III, Chester O.; Beckman, Andrew T., Charging system that enables emergency resolutions for charging a battery.
  13. Baber, Daniel L.; Swayze, Jeffrey S.; Beckman, Andrew T.; Miller, Christopher C.; Scheib, Charles J.; Float, Jamison J.; O'Kelly, Matthew E., Circuitry and sensors for powered medical device.
  14. Cropper, Michael S.; Setser, Michael E.; Jamison, Barry T.; Kistler, Paul H.; Dugan, John R.; Patel, Sudhir B., Closure lockout systems for surgical instruments.
  15. Harris, Jason L.; Shelton, IV, Frederick E.; Vendely, Michael J., Compressible adjuncts with bonding nodes.
  16. Jacobsen, Stephen C.; Maclean, Brian J.; Pensel, Ralph W.; Hirschi, Christopher R., Conformable track assembly for a robotic crawler.
  17. Jacobsen, Stephen C.; Maclean, Brian J.; Pensel, Ralph W.; Hirschi, Christopher R., Conformable track assembly for a robotic crawler.
  18. Shelton, IV, Frederick E.; Harris, Jason L.; Beckman, Andrew T., Control techniques and sub-processor contained within modular shaft with select control processing from handle.
  19. Smith, Fraser M., Coordinated robotic control.
  20. Leimbach, Richard L.; Lytle, IV, Thomas W.; Sackett, Kevin D.; Overmyer, Mark D., Drive train control arrangements for modular surgical instruments.
  21. Schmid, Katherine J.; Morgan, Jerome R.; Korvick, Donna L.; Shelton, IV, Frederick E., End effector comprising a tissue thickness compensator and progressively released attachment members.
  22. Leimbach, Richard L.; Shelton, IV, Frederick E.; Morgan, Jerome R.; Schellin, Emily A., End effector detection and firing rate modulation systems for surgical instruments.
  23. Shelton, IV, Frederick E.; Schmid, Katherine J.; Scheib, Charles J.; Aronhalt, Taylor W.; Swayze, Jeffrey S.; Contiliano, Joseph H.; Yang, Chunlin; Henderson, Cortney E.; Aldridge, Jeffrey L., End effector including an implantable arrangement.
  24. Shelton, IV, Frederick E.; Young, Joseph E.; Aronhalt, Taylor W.; Baxter, III, Chester O., End effector with implantable layer.
  25. Zubiate, Brett; Choset, Howard, Extendable articulated probe device.
  26. Zubiate, Brett; Choset, Howard, Extendable articulated probe device.
  27. Swayze, Jeffrey S.; Hueil, Joseph C.; Morgan, Jerome R.; Shelton, IV, Frederick E., Fastener cartridge assembly comprising a fixed anvil.
  28. Shelton, IV, Frederick E., Implantable layer assemblies.
  29. Roberts, Herbert Chidsey; Diwinsky, David Scott; Grady, Wayne R., In situ gas turbine prevention of crack growth progression.
  30. Roberts, Herbert Chidsey; Diwinsky, David Scott; Grady, Wayne R., In situ gas turbine prevention of crack growth progression.
  31. Park, Heum Yong; Kim, Yong Jae; Kim, Jeong Hun; Lee, Youn Baek, Link unit, arm module, and surgical apparatus including the same.
  32. Morgan, Jerome R.; Baxter, III, Chester O.; Shelton, IV, Frederick E.; Knight, Gary W., Locking arrangements for detachable shaft assemblies with articulatable surgical end effectors.
  33. Shelton, IV, Frederick E.; Morgan, Jerome R., Manipulatable surgical systems with selectively articulatable fastening device.
  34. Shelton, IV, Frederick E.; Overmyer, Mark D.; Yates, David C.; Harris, Jason L., Mechanisms for compensating for drivetrain failure in powered surgical instruments.
  35. Jacobsen, Stephen C.; Olivier, Marc X.; Pensel, Ralph W.; Smith, Fraser M., Method and system for deploying a surveillance network.
  36. Jacobsen, Stephen C.; Marceau, David P., Method for manufacturing a complex structure.
  37. Motzer, William P.; Georgeson, Gary E.; Lea, Scott W.; Hellenbrand, Peter J.; Troy, James J., Methods and systems for inspection sensor placement.
  38. Larkin, David Q.; Cooper, Thomas G.; Shafer, David C.; Rosa, David J.; Williams, Matthew R.; Duval, Eugene F., Minimally invasive surgery instrument assembly with reduced cross section.
  39. Pikulski, Joseph L., Mobilized cooler device with fork hanger assembly.
  40. Jacobsen, Stephen C.; Olivier, Marc X., Modular robotic crawler.
  41. Beckman, Andrew T.; Shelton, IV, Frederick E.; Morgan, Jerome R.; Yates, David C.; Baxter, III, Chester O.; Uth, Joshua R.; Savage, Jeffrey L.; Harris, Jason L., Modular stapling assembly.
  42. Shelton, IV, Frederick E., Motor-driven surgical instrument.
  43. Zubiate, Brett; Choset, Howard, Multi-linked device having a reinforcing member.
  44. Zubiate, Brett; Choset, Howie, Multi-linked device having a reinforcing member.
  45. Zubiate, Brett; Choset, Howie, Multi-linked device having a reinforcing member.
  46. Zubiate, Brett; Choset, Howard; Degani, Amir; Kolb, Anthony; GilMartin, Kevin P.; Flaherty, J. Christopher, Multi-linked endoscopic device with spherical distal assembly.
  47. Jacobsen, Stephen C.; Olivier, Marc X., Point and go navigation system and method.
  48. Baber, Daniel L.; Swayze, Jeffrey S.; Beckman, Andrew T.; Posada, Sol A., Polarity of hall magnet to identify cartridge type.
  49. Shelton, IV, Frederick E.; Morgan, Jerome R.; Harris, Jason L.; Beckman, Andrew T.; Baxter, III, Chester O., Power adapter for a surgical instrument.
  50. Smith, Bret W.; Abbott, Daniel J.; Schwemberger, Richard F.; Shelton, IV, Frederick E.; Boudreaux, Chad P.; Swensgard, Brett E.; Laurent, Ryan J., Powered surgical cutting and stapling apparatus with manually retractable firing system.
  51. Buckingham, Robert Oliver; Graham, Andrew Crispin, Robotic arms.
  52. Yates, David C.; Shelton, IV, Frederick E.; Morgan, Jerome R., Robotically-controlled motorized surgical instrument with an end effector.
  53. Jacobsen, Stephen C., Serpentine robotic crawler.
  54. Pensel, Ralph W., Serpentine robotic crawler.
  55. Smith, Fraser M., Serpentine robotic crawler.
  56. Smith, Fraser M.; Olivier, Marc; McCullough, John, Serpentine robotic crawler for performing dexterous operations.
  57. Cooper, Thomas G.; Rosa, David J.; Larkin, David Q.; Williams, Matthew R.; Duval, Eugene F., Side looking minimally invasive surgery instrument assembly.
  58. Cooper, Thomas G.; Rosa, David J.; Larkin, David Q.; Williams, Matthew R.; Duval, Eugene F., Side looking minimally invasive surgery instrument assembly.
  59. Cooper, Thomas G.; Rosa, David J.; Larkin, David Q.; Williams, Matthew R.; Duval, Eugene F., Side looking minimally invasive surgery instrument assembly.
  60. Cooper, Thomas G.; Rosa, David J.; Williams, Matthew R.; Duval, Eugene F., Side looking minimally invasive surgery instrument assembly.
  61. Cooper, Thomas G.; Rosa, David J.; Williams, Matthew R.; Duval, Eugene F., Side looking minimally invasive surgery instrument assembly.
  62. Baber, Daniel L.; Swayze, Jeffrey S.; Beckman, Andrew T.; Shelton, IV, Frederick E., Smart cartridge wake up operation and data retention.
  63. Georgeson, Gary E., Stabilization of an end of an extended-reach apparatus in a limited-access space.
  64. Shelton, IV, Frederick E.; Baxter, III, Chester O., Staple cartridge assembly comprising an implantable layer.
  65. Shelton, IV, Frederick E.; Weaner, Lauren S.; Morgan, Jerome R.; Vendely, Michael J.; Aronhalt, Taylor W.; Baxter, III, Chester O.; Zeiner, Mark S., Staple cartridge comprising a tissue thickness compensator.
  66. Shelton, IV, Frederick E.; Swayze, Jeffrey S.; Morgan, Jerome R., Staple cartridge comprising staples with different unformed heights.
  67. Shelton, IV, Frederick E., Staple cartridges for forming staples having differing formed staple heights.
  68. Shelton, IV, Frederick E.; Baxter, III, Chester O.; Aronhalt, Taylor W., Stapling assemblies comprising a layer.
  69. Swayze, Jeffrey S.; Hueil, Joseph C.; Morgan, Jerome R.; Shelton, IV, Frederick E., Stapling assembly configured to produce different formed staple heights.
  70. Shelton, IV, Frederick E.; Harris, Jason L., Stapling end effector configured to compensate for an uneven gap between a first jaw and a second jaw.
  71. Schmid, Katherine J.; Morgan, Jerome R.; Korvick, Donna L.; Shelton, IV, Frederick E., Stapling system comprising an adjunct and a flowable adhesive.
  72. Shelton, IV, Frederick E.; Baxter, III, Chester O.; Aronhalt, Taylor W.; Young, Joseph E., Stapling system including an actuation system.
  73. Zubiate, Brett; Degani, Amir; Choset, Howie, Steerable multi linked device having multiple working ports.
  74. Zubiate, Brett; Choset, Howard M.; Degani, Amir; Schwerin, Michael, Steerable multi-linked device having a modular link assembly.
  75. Zubiate, Brett; Choset, Howard M.; Degani, Amir; Schwerin, Michael, Steerable multi-linked device having a modular link assembly.
  76. Zubiate, Brett; Choset, Howard; Degani, Amir; Schwerin, Michael, Steerable multi-linked device having a modular link assembly.
  77. Zubiate, Brett; Choset, Howard; Degani, Amir; Schwerin, Michael, Steerable multi-linked device having a modular link assembly.
  78. Zubiate, Brett; Degani, Amir; Choset, Howie, Steerable multi-linked device having multiple working ports.
  79. Zubiate, Brett; Degani, Amir; Choset, Howie, Steerable multi-linked device having multiple working ports.
  80. Choset, Howard M.; Wolf, Alon; Zenati, Marco A., Steerable, follow the leader device.
  81. Choset, Howard M.; Wolf, Alon; Zenati, Marco A., Steerable, follow the leader device.
  82. Choset, Howard M.; Wolf, Alon; Zenati, Marco A., Steerable, follow the leader device.
  83. Choset, Howard M.; Wolf, Alon; Zenati, Marco A., Steerable, follow the leader device.
  84. Beckman, Andrew T.; Nalagatla, Anil K.; Hibner, John A.; Shelton, IV, Frederick E., Surgical apparatus configured to assess whether a performance parameter of the surgical apparatus is within an acceptable performance band.
  85. Beckman, Andrew T.; Nalagatla, Anil K.; Koch, Jr., Robert L.; Hibner, John A.; Shelton, IV, Frederick E., Surgical apparatus configured to track an end-of-life parameter.
  86. Shelton, IV, Frederick E., Surgical cutting and fastening instrument.
  87. Baxter, III, Chester O.; Swayze, Jeffrey S.; Dunki-Jacobs, Adam R., Surgical end effectors with dual cam actuated jaw closing features.
  88. Shelton, IV, Frederick E.; Swayze, Jeffrey S.; Baxter, III, Chester O., Surgical fastening apparatus with a rotary end effector drive shaft for selective engagement with a motorized drive system.
  89. Shelton, IV, Frederick E.; Morgan, Jerome R.; Harris, Jason L.; Swayze, Jeffrey S.; Baxter, III, Chester O., Surgical instrument assembly comprising a flexible articulation system.
  90. Baxter, III, Chester O.; Dunki-Jacobs, Adam R.; Swayze, Jeffrey S.; Baber, Daniel L.; Shelton, IV, Frederick E., Surgical instrument assembly comprising a lockable articulation system.
  91. Yates, David C.; Huitema, Thomas W.; Shelton, IV, Frederick E., Surgical instrument comprising a control system.
  92. Parihar, Shailendra K.; Kimsey, John S.; Koch, Jr., Robert L.; Nalagatla, Anil K.; Nguyen, Anthony T., Surgical instrument comprising a gap setting system.
  93. Overmyer, Mark D.; Auld, Michael D.; Adams, Shane R.; Shelton, IV, Frederick E.; Harris, Jason L., Surgical instrument comprising a lockable battery housing.
  94. Morgan, Jerome R.; Shelton, IV, Frederick E., Surgical instrument comprising a plurality of articulation joints.
  95. Leimbach, Richard L.; Beckman, Andrew T.; Schultz, Darwin L.; Adams, Shane R., Surgical instrument comprising a rotatable shaft.
  96. Shelton, IV, Frederick E.; Swayze, Jeffrey S., Surgical instrument comprising drive systems.
  97. Morgan, Jerome R.; Shelton, IV, Frederick E., Surgical instrument system comprising a firing system including a rotatable shaft and first and second actuation ramps.
  98. Savage, Jeffrey L.; Uth, Joshua R.; Beckman, Andrew T.; Baxter, III, Chester O., Surgical instrument system comprising an inspection station.
  99. Kerr, Wendy A.; Lytle, IV, Thomas W.; Overmyer, Mark D.; Swensgard, Brett E.; Sackett, Kevin D.; Leimbach, Richard L.; Houser, Kevin L.; Morgan, Jerome R.; Shelton, IV, Frederick E., Surgical instrument system comprising lockable systems.
  100. Morgan, Jerome R.; Shelton, IV, Frederick E., Surgical instrument system configured to detect resistive forces experienced by a tissue cutting implement.
  101. Yates, David C.; Shelton, IV, Frederick E.; Giordano, James R., Surgical instrument system for evaluating tissue impedance.
  102. Shelton, IV, Frederick E.; Baxter, III, Chester O., Surgical instrument with an anvil that is selectively movable about a discrete non-movable axis relative to a staple cartridge.
  103. Hunter, Morgan R.; Schultz, Darwin L.; Worthington, Sarah A.; Shelton, IV, Frederick E.; Weaner, Lauren S.; Vendely, Michael J., Surgical instrument with articulating and axially translatable end effector.
  104. Shelton, IV, Frederick E.; Baxter, III, Chester O.; Harris, Jason L.; Swayze, Jeffrey S., Surgical instruments with articulatable end effectors and improved firing beam support arrangements.
  105. Hunter, Morgan R.; Schultz, Darwin L.; Dunki-Jacobs, Adam R.; Baxter, III, Chester O.; Swayze, Jeffrey S., Surgical instruments with tensioning arrangements for cable driven articulation systems.
  106. Adams, Shane R.; Yates, David C.; Shelton, IV, Frederick E.; Harris, Jason L., Surgical shaft assemblies with watertight housings.
  107. Harris, Jason L.; Morgan, Jerome R.; Zeiner, Mark S.; Shelton, IV, Frederick E., Surgical staple and driver arrangements for staple cartridges.
  108. Murray, Michael A.; Morgan, Jerome R.; Hess, Christopher J.; Weisenburgh, II, William B.; Zwolinski, Andrew M., Surgical staple cartridge.
  109. Yates, David C.; Shelton, IV, Frederick E., Surgical stapler having current mirror-based motor control.
  110. Yates, David C.; Shelton, IV, Frederick E., Surgical stapler having downstream current-based motor control.
  111. Overmyer, Mark D.; Yates, David C.; Shelton, IV, Frederick E.; Adams, Shane R.; Leimbach, Richard L., Surgical stapler having motor control based on an electrical parameter related to a motor current.
  112. Overmyer, Mark D.; Yates, David C.; Shelton, IV, Frederick E.; Adams, Shane R.; Harris, Jason L., Surgical stapler having temperature-based motor control.
  113. Baxter, III, Chester O.; Shelton, IV, Frederick E.; Ballard, Kenneth D., Surgical staples comprising features for improved fastening of tissue.
  114. Huang, Zhifan F.; Morgan, Jerome R.; Shelton, IV, Frederick E., Surgical stapling apparatus comprising a tissue stop.
  115. Shelton, IV, Frederick E.; Setser, Michael E.; Weisenburgh, II, William B., Surgical stapling instrument with lockout features to prevent advancement of a firing assembly unless an unfired surgical staple cartridge is operably mounted in an end effector portion of the instrument.
  116. Shelton, IV, Frederick E.; Morgan, Jerome R., Surgical stapling instruments with rotatable staple deployment arrangements.
  117. Shelton, IV, Frederick E.; Morgan, Jerome R., Surgical system with selectively articulatable end effector.
  118. Diwinsky, David Scott; Lim, Ser Nam, System and method for locating a probe within a gas turbine engine.
  119. Diwinsky, David Scott; Lim, Ser Nam, System and method for locating a probe within a gas turbine engine.
  120. Shelton, IV, Frederick E.; Harris, Jason L.; Yates, David C., System for controlling articulation forces.
  121. Zubiate, Brett; Degani, Amir; Choset, Howie, System for releasably attaching a disposable device to a durable device.
  122. Zubiate, Brett; Degani, Amir; Choset, Howie, System for releasably attaching a disposable device to a durable device.
  123. Leimbach, Richard L.; Adams, Shane R.; Overmyer, Mark D.; Swensgard, Brett E.; Lytle, IV, Thomas W.; Shelton, IV, Frederick E.; Houser, Kevin L., Systems and methods for controlling a segmented circuit.
  124. Shelton, IV, Frederick E.; Swensgard, Brett E.; Leimbach, Richard L.; Adams, Shane R.; Overmyer, Mark D.; Houser, Kevin L., Systems and methods for controlling a segmented circuit.
  125. Larkin, David Q., Teleoperated surgical retractor system.
  126. Shelton, IV, Frederick E.; Harris, Jason L.; Swensgard, Brett E.; Leimbach, Richard L.; Adams, Shane R.; Overmyer, Mark D., Time dependent evaluation of sensor data to determine stability, creep, and viscoelastic elements of measures.
  127. Shelton, IV, Frederick E.; Harris, Jason L.; Swensgard, Brett E.; Leimbach, Richard L.; Adams, Shane R.; Overmyer, Mark D., Time dependent evaluation of sensor data to determine stability, creep, and viscoelastic elements of measures.
  128. Jacobsen, Stephen C., Tracked robotic crawler having a moveable arm.
  129. Jacobsen, Stephen C.; Marceau, David P., Two-dimensional layout for use in a complex structure.

관련 콘텐츠

섹션별 컨텐츠 바로가기

AI-Helper ※ AI-Helper는 오픈소스 모델을 사용합니다.

AI-Helper 아이콘
AI-Helper
안녕하세요, AI-Helper입니다. 좌측 "선택된 텍스트"에서 텍스트를 선택하여 요약, 번역, 용어설명을 실행하세요.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.

선택된 텍스트

맨위로