US 6,115,114 A · Laser scanning system and applications

Abstract

A laser scanner sensor for measuring the spatial properties of objects in a scene within a range less than a predetermined maximum object distance. Applications of the laser scanner system includes measurement of the dimensional weight of parcel(s) being transported by a moving forklift. In the laser scanner sensor, a laser diode supplies a laser beam that is intensity-modulated by a reference waveform from a waveform generator. A variation of the optical scanning sensor system scans a field of measurement which the moving forklift traverses. The forklift has at least three retroreflectors attached to act as calibration targets within the viewing field. The scanner system intensity-modulates the laser beam, and receives reflected intensity-modulated light and supplies it to an optical processing system that includes an aperture that transmits a first percentage of light reflected from the maximum object distance and a second, lesser percentage of light reflected from objects closer than the maximum object distance. A photodetector receives the processed light and converts the energy into an amplitude-modulated range signal. Range values are then determined about every 0.1-inches along a scan line. A number of scan lines are assembled in the computer and displayed on a screen as a 3-D image. The 3-D image is then analyzed by the computer to extract the volume of the objects carried on the forklift tines. The volume is then converted to Dimensional Weight (DIM WT) which is used by the shipper to determine tare.

Claims12

Dependent claims

A method for measuring volume of a moving parcel, the method comprising

placing a parcel on a forklift to which at least three retroreflectors are attached, the retroreflectors having a fixed geometrical relationship;
transporting the parcel into a field of measurement;
transmitting a laser beam from a scanner sensor system transverse to a velocity vector of the forklift carrying the parcel;
reflecting the laser beam from the field of measurement containing the forklift and the parcel forming a scan image;
determining an aspect and a length, width and height of the parcel by processing the scan image in relation to measured distances between the retroreflectors and rate of motion of the retroreflectors;
and
determining a volume of the parcel.

4 more elements

A method for measuring volume of a transported parcel in motion, the method comprising the steps of:

placing and moving a parcel by a transporting machine comprising a forklift having at least three retroreflectors, a scale weighing device, and a bar code reader device;
transporting the parcel through a scanning field of measurement;
transmitting a scanning laser beam from a laser scanner sensor system transverse to an axis of directional motion of the transporting machine;
receiving a reflected beam from the field of measurement by the laser scanner sensor system forming a scan image of the parcel and the transporting machine including the at least three retroreflectors;
measuring weight of the parcel and determining a dimensional weight of the parcel and affixing a bar code identification to the parcel, wherein the measured parcel weight and identification information is transmitted to a parcel processing system by use of the scale weighing device and the bar code reader device;
determining an aspect and a height of the parcel by processing the scan image in relation to rate of motion of the transporting machine;
and
determining the volume of the parcel including the preliminary steps of calibrating the scanner sensor system measurements by determining scan line distance between each of the at least three retroreflectors resulting from the rate of motion of the transporting machine.

5 more elements

A system for measuring volume of a parcel moving in a field of measurement, the system comprising:

a supporting means for supporting and transporting a parcel placed thereupon for measurement in a scanning field of measurement, the supporting means comprising a forklift having at least three retroreflectors and means for measuring weight of the parcel, wherein the means for measuring weight is structurally interconnected to the tines of the forklift;
a laser scanner sensor means for scanning a predetermined field for measurement data wherein the measurement data is representative of said parcel's aspect and height above a reference plane in relation to the scanner sensor means wherein:
(a) the scanner sensor means is positioned at a predetermined location in relation to the supporting means,
(b) the scanner sensor means emits a beam at the supporting means which transversely scans the supporting means while moving through the field of measurement, and
(c) the scanner sensor means receives a reflection of the emitted beam and the received beam is used to determine the measurement data from reflected light from the scanning field of measurement;
and
processor means for determining the parcel's aspect and height from the measurement data and outputting a volumetric measurement of the parcel.

4 more elements

Dependencies are inferred from the claim text.

Laser scanning system and applications

Life of this patent

Laser scanning system and applications

Life of this patent

Abstract

Claims12