Object-sensing systems and robotic systems including the same
Object-sensing systems including a light transmitter subsystem and a light receiver subsystem. The light transmitter subsystem main be configured to generate a collimated linear beam of light at a predetermined wavelength and having a length of at least 3 inches. The light receiver subsystem may include a linear sensor array having a length of at least 3 inches. The linear sensor array may be positioned to receive the collimated linear beam of light and to detect shadows caused by objects blocking at least a portion of the collimated linear beam of light. Various other systems and methods are also disclosed.
1 . An object-sensing system, comprising:
a light transmitter subsystem configured to generate a collimated linear beam of light at a predetermined wavelength and having a length of at least 3 inches, the light transmitter subsystem comprising:
a laser light source;
a collimator positioned and configured to collimate laser light from the laser light source into a collimated laser light beam;
a Powell lens positioned and configured to form a linear fan of light from the collimated laser light beam; and
a linear lens positioned and configured to convert the linear fan of light from the Powell lens into the collimated linear beam of light; and
a light receiver subsystem comprising a linear sensor array having a length of at least 3 inches, the light receiver subsystem positioned to receive the collimated linear beam of light from the linear lens, to detect shadows caused by objects blocking at least a portion of the collimated linear beam of light, and to determine a presence of obstacles based at least in part on the shadows caused by the objects exceeding a predetermined threshold size.
2 . The object-sensing system of claim 1 , wherein the linear lens is selected from the group consisting of:
a Fresnel lens; or
a cylindrical lens.
3 . The object-sensing system of claim 1 , wherein the Powell lens is positioned at a focal point of the linear lens.
4 . The object-sensing system of claim 1 , further comprising one or more plane mirrors between the Powell lens and the linear lens positioned to shorten a distance between the Powell lens and the linear lens.
5 . The object-sensing system of claim 1 , wherein the linear lens has a lateral width of 3 mm or less.
6 . The object-sensing system of claim 1 , wherein the light receiver subsystem further comprises a band pass filter over the linear sensor array, the band pass filter configured to allow passage of light at the predetermined wavelength.
7 . The object-sensing system of claim 1 , wherein the light receiver subsystem further comprises a louver film over the linear sensor array, the louver film configured to allow passage of light at an angle of the collimated linear beam of light.
8 . The object-sensing system of claim 1 , wherein the object-sensing system has a mass of less than 400 grams.
9 . The object-sensing system of claim 1 , wherein the light transmitter subsystem is configured to generate the collimated linear beam of light having a length of at least 5 inches and the linear sensor array has a length of at least 5 inches.
10 . The object-sensing system of claim 1 , wherein the linear sensor array has a width of one to five sensor pixels.
11 . The object-sensing system of claim 10 , wherein the linear sensor array has a width of only one sensor pixel.
12 . The object-sensing system of claim 1 , wherein the linear sensor array has a resolution of at least 200 pixels per inch in length.
13 . The object-sensing system of claim 12 , wherein the linear sensor array has a resolution of at least 300 pixels per inch in length.
14 . The object-sensing system of claim 1 , wherein the predetermined wavelength is an infrared wavelength.
15 . A robotic system for suspending cable from an overhead powerline, the system comprising:
a drive subsystem for driving the robotic system along the powerline;
an obstacle detection subsystem for detecting obstacles along the powerline, the obstacle detection subsystem comprising:
a light transmitter subsystem positioned on a first side of the powerline and configured to generate a collimated linear beam of light having a length of at least 3 inches, the light transmitter subsystem comprising:
a laser light source;
a collimator positioned and configured to collimate laser light from the laser light source into a collimated laser light beam;
a Powell lens positioned and configured to form a linear fan of light from the collimated laser light beam; and
a linear lens positioned and configured to convert the linear fan of light from the Powell lens into the collimated linear beam of light;
a light receiver subsystem positioned on a second, opposite side of the powerline and comprising a linear sensor array having a length of at least 3 inches, the light receiver subsystem positioned to receive the collimated linear beam from the linear lens, to detect shadows caused by the obstacles blocking at least a portion of the collimated linear beam of light, and to determine a presence of obstacles based at least in part on the shadows caused by the objects exceeding a predetermined threshold size, wherein the predetermined threshold size is defined by a width of the powerline; and
an extension subsystem for moving at least a portion of the robotic system to avoid the obstacles detected by the obstacle detection subsystem.
16 . The system of claim 15 , wherein the light receiver subsystem comprises:
a band pass filter over the linear sensor array, the band pass filter configured to allow passage of light at a wavelength of the collimated linear beam of light; and
a louver film over the linear sensor array, the louver film configured to allow passage of light at an angle of the collimated linear beam of light.
17 . The system of claim 15 , wherein the collimated linear beam of light has a length of at least 5 inches and the linear sensor array has a length of at least 5 inches, a width of three or fewer pixels, and a resolution of at least 200 pixels per inch in length.
18 . A method of fabricating an object-sensing system, the method comprising:
operatively coupling a collimator to a laser light source such that the collimator forms a collimated beam of light from laser light from the laser light source;
positioning a Powell lens to receive the collimated beam of light and to form a linear fan of light from the collimated beam of light;
positioning a linear lens to receive the linear fan of light and to form a collimated linear beam of light from the linear fan of light, the collimated linear beam of light having a length of at least 3 inches;
positioning a linear sensor array having a length of at least 3 inches to receive the collimated linear beam of light from the linear lens, and to detect shadows caused by objects blocking at least a portion of the collimated linear beam of light;
operatively coupling a signal processor to the linear sensor array, the signal processor configured to determine a presence of obstacles based at least in part on the shadows caused by the objects exceeding a predetermined threshold size.