John Hancock - Academia.edu (original) (raw)

Papers by John Hancock

Research paper thumbnail of Laser intensity-based obstacle detection

Proceedings. 1998 IEEE/RSJ International Conference on Intelligent Robots and Systems. Innovations in Theory, Practice and Applications (Cat. No.98CH36190)

We present a novel method for obstacle detection for automated highway environments. Laser range ... more We present a novel method for obstacle detection for automated highway environments. Laser range scanners have frequently been used for obstacle detection for mobile robots. Although most laser scanners provide intensity information in addition to range, laser intensity has been ignored by most researchers. We show that laser intensity, on its own, is sufficient (and better) for detecting obstacles at long ranges in mild terrain such as an automated highway.

Research paper thumbnail of High-performance laser range scanner

SPIE Proceedings, 1998

Laser scanners, or ladars, have been used for a number of years for mobile robot navigation. Alth... more Laser scanners, or ladars, have been used for a number of years for mobile robot navigation. Although previous scanners were sufficient for low-speed navigation, they often did not have the range or angular resolution necessary for mapping at the long distances required by high-speed navigation. Many also did not provide an ample field of view. In this paper we will present the development of state-of-the-art, high speed, high accuracy, laser range scanner technology This work has been a joint effort between CMU (project lead) and K2T (scanning mechanism) in Pittsburgh and Zoller + Friihlich (laser) in Wangen, Germany. The scanner mechanism provides an unobstructed 360' horizontal field of view, and a 30' vertical field of view. Rcsolution of thc scanner is variablc with a maximum resolution of approximately 0.06 degrees per pixel in both azimuth and clcvation. The laser is amplitude-modulated, continuous-wave with an ambiguity interval of 52 meters, a range resolution of I .6 mni, and a maximum pixcl rate of 500 kHz. This paper will focus on the design and performance of the scanner mechanism and will discuss several potential applications for the technology. Onc application, obstacle detection for Automated Highway applications will be discussed in more detail. Example data will bc shown and current mechanism improvements from the CMU prototype will also be discussed.

Research paper thumbnail of For High-Performance Measurements

Laser scanners, or laser radars (ladar), have been used for a number of years for mobile robot na... more Laser scanners, or laser radars (ladar), have been used for a number of years for mobile robot navigation and inspection tasks. Although previous scan- ners were sufficient for low speed applications, they often did not have the range or angular resolution necessary for mapping at the long distances. Many also did not provide an ample field of view with high accuracy and high precision. In this paper we will present the development of state-of- the-art, high speed, high accuracy, 3D laser radar techno- logy. This work has been a joint effort between CMU and K2T and Z+F. The scanner mechanism provides an unob- structed 360° horizontal field of view, and a 70° vertical field of view, Resolution of the scanner is variable with a maximum resolution of approximately 0.06 degrees per pixel in both azimuth and elevation, The laser is ampli- tude-modulated, continuous-wave with an ambiguity interval of 52m, a range resolution of 1.6mm, and a maxi- mum pixel rate of 625kHz. This paper will f...

Research paper thumbnail of Laser intensity-based obstacle detection

Proceedings. 1998 IEEE/RSJ International Conference on Intelligent Robots and Systems. Innovations in Theory, Practice and Applications (Cat. No.98CH36190)

We present a novel method for obstacle detection for automated highway environments. Laser range ... more We present a novel method for obstacle detection for automated highway environments. Laser range scanners have frequently been used for obstacle detection for mobile robots. Although most laser scanners provide intensity information in addition to range, laser intensity has been ignored by most researchers. We show that laser intensity, on its own, is sufficient (and better) for detecting obstacles at long ranges in mild terrain such as an automated highway.

Research paper thumbnail of High-performance laser range scanner

SPIE Proceedings, 1998

Laser scanners, or ladars, have been used for a number of years for mobile robot navigation. Alth... more Laser scanners, or ladars, have been used for a number of years for mobile robot navigation. Although previous scanners were sufficient for low-speed navigation, they often did not have the range or angular resolution necessary for mapping at the long distances required by high-speed navigation. Many also did not provide an ample field of view. In this paper we will present the development of state-of-the-art, high speed, high accuracy, laser range scanner technology This work has been a joint effort between CMU (project lead) and K2T (scanning mechanism) in Pittsburgh and Zoller + Friihlich (laser) in Wangen, Germany. The scanner mechanism provides an unobstructed 360' horizontal field of view, and a 30' vertical field of view. Rcsolution of thc scanner is variablc with a maximum resolution of approximately 0.06 degrees per pixel in both azimuth and clcvation. The laser is amplitude-modulated, continuous-wave with an ambiguity interval of 52 meters, a range resolution of I .6 mni, and a maximum pixcl rate of 500 kHz. This paper will focus on the design and performance of the scanner mechanism and will discuss several potential applications for the technology. Onc application, obstacle detection for Automated Highway applications will be discussed in more detail. Example data will bc shown and current mechanism improvements from the CMU prototype will also be discussed.

Research paper thumbnail of For High-Performance Measurements

Laser scanners, or laser radars (ladar), have been used for a number of years for mobile robot na... more Laser scanners, or laser radars (ladar), have been used for a number of years for mobile robot navigation and inspection tasks. Although previous scan- ners were sufficient for low speed applications, they often did not have the range or angular resolution necessary for mapping at the long distances. Many also did not provide an ample field of view with high accuracy and high precision. In this paper we will present the development of state-of- the-art, high speed, high accuracy, 3D laser radar techno- logy. This work has been a joint effort between CMU and K2T and Z+F. The scanner mechanism provides an unob- structed 360° horizontal field of view, and a 70° vertical field of view, Resolution of the scanner is variable with a maximum resolution of approximately 0.06 degrees per pixel in both azimuth and elevation, The laser is ampli- tude-modulated, continuous-wave with an ambiguity interval of 52m, a range resolution of 1.6mm, and a maxi- mum pixel rate of 625kHz. This paper will f...