KR20030060924A - Chassis alignment system - Google Patents

Abstract

A system for alignment of a truck chassis and a method and computer software means for carrying out same. The system comprises a laser scanner measuring means. The system measures distances to a load accurately despite changes in lighting condition due to weather. No reflective markings are needed on the trucks or containers.

Description

Chassis Alignment System {CHASSIS ALIGNMENT SYSTEM}

Technical field

The present invention relates to a system and method for positioning a container fixed by a crane. In particular, but not by way of limitation, the invention is a method and system for aligning chassis of a truck or other vehicle carrying a container so that the container can be lowered or lifted by the crane.

Technical background

Around the world, large quantities of cargo are shipped in standard shipping containers. At each point of movement from one vehicle to another, for example at a port or port, a huge number of containers must be unloaded, transferred to a temporary stack, and later loaded on another ship or other form of vehicle. There is. In order to achieve the shortest unloading and loading times, the container handling facility must be fully or partially fully automated during normal operation.

The technical demand to manipulate containers is large. In general, the container's own weight is consistent but the overall weight is significantly different. The width of the shipping container is standardized to 8ft, but the height varies between 8ft and 9.5ft. The most common standard lengths are 20ft and 40ft. Currently 40ft containers are very common, and longer containers with lengths up to 53ft are also used.

Containers can be operated by cranes, cranes moving on rails, self-propelled container handling devices, and lifts or winches of all types referred to herein as cranes. Each crane has a lifting device that generally incorporates some kind of spreader in direct contact with the container to grasp, lift, lower, and release the container. As used herein, the term "spreader" may be used to refer to a portion of a lifting device that is in direct contact with a container. Typically, spreaders are designed to manipulate containers of one or more sizes, generally 20-40ft or 20-40-45ft. Cranes and other automatic container handling devices and systems are used to accelerate the process of loading and unloading containers delivered from one point to another.

The point of delivery of the container between the crane and the truck may be the cause of the delay. In general, a crane is located above one or more parallel loading / unloading lanes where a truck or other vehicle, hereinafter referred to as a truck chassis, is installed to load containers into or unload containers from the crane. In general, cranes are installed with limited freedom to move the spreader in a direction parallel to the constriction of the loading / unloading lanes, and it is important for the truck driver to position the truck chassis correctly under the crane. Incorrect positioning of the truck chassis causes delays in the delivery of containers.

US 5,142,658 describes a container chassis positioning system. The system uses a video camera to capture images of the truck chassis, and the images are compared by computer with stored templates corresponding to known parts of the truck of known type. These images are processed as gray scale images and matched using statistical probabilistic methods to determine close matches. The relative position of the truck and the container is determined, and the actual stop point is signaled to the driver of the truck. The signal is carried out by a number of lamps in the system that are progressively lit to indicate that the truck is traveling to the correct position.

However, processing video images and gray scale images requires significant computer processing power to process such images quickly. In addition, it may be practically difficult to recognize a truck chassis using video imaging based on graphical images such as gray scale. The color intensity of chassis parts photographed with asphalt as background changes with the contrast and color of the truck chassis and the color contrast between them. In particular, under dim light or harsh weather conditions, truck chassis recognition can be achieved using video-based images of that type without further relying on fixing lamps or highly reflective signs or markers on the chassis for fast and reliable recognition. It can be difficult to do.

Summary of the Invention

One object of the present invention is to enable the driver of a truck chassis to position the truck to correctly receive the container.

Another object of the present invention is to allow the positioning of the truck chassis to accommodate the container in one of a plurality of loading positions on the truck chassis.

According to other aspects of the invention, there is provided a method as claimed in claim 1, a system according to claim 11, a computer program product according to claim 18, and a signal according to claim 20. do.

The main advantage provided by the present invention is to provide a precise system for quickly and easily recognizing truck chassis even in dim light or harsh weather conditions. This facility accelerates the automatic operation of the container. The present invention can be used in a standard vehicle without first installing a special sign or light reflection marker at certain points on the truck, so that automatic recognition functions properly. This also means that the system according to the invention can continue to function even under conditions in which rain and dust like signs or markers may become unclear.

The present invention relies on a three-dimensional (3-D) laser camera that scans an object and measures a fixed point or the distance between the camera and the measured object. The scanned image depends on the distance to the physical object, and each other does not depend on the color or contrast between the objects. By this means, the present invention provides a fast and accurate system and method for measuring the distance to a truck chassis or container.

In addition, the present invention signals the truck driver the correct position, allowing the driver to position the truck chassis precisely with respect to the loading position, regardless of whether the truck chassis is in front of, behind, or in the middle of the truck chassis. In this regard, the present invention enables the high speed transportation of containers from or to a truck chassis, regardless of whether the containers are the same length or different lengths.

A particular advantage and great benefit of the system is that CAS opens up all lanes and can guide truck drivers in the right order by: The time to determine the chassis position is approximately 1 s or so in the crane direction and 2 s in the trolley direction, which makes the positioning faster when compared to manual adjustment. It consists of just one sensor and a truck driver's guide light bar. In an advantageous embodiment, the CAS has an interface to both automatic positioning systems and full manual crane control, which is flexible enough to be used with new or old existing cranes. 3-D laser technology is strong and reliable in all weather conditions.

The CAS 3-D laser system is Class 1, which makes it safe for people to work under and around cranes.

The present invention can be applied to existing facilities as well as new facilities. When combined with an automatic crane control system capable of receiving positioning data from the CAS system, it further aids in the automatic landing of containers.

Brief description of the drawings

Hereinafter, embodiments of the present invention will be described by way of example only with reference to the accompanying drawings in detail.

1 is a schematic diagram of one mounting position for a system in accordance with one embodiment of the present invention.

7 is a schematic diagram schematically showing an indicator bar as an array of signal lamps according to an embodiment of the system according to the invention.

6 is a top schematic view of a crane gantry and trolley positioned above multiple truck chassis in a loading / unloading lane.

8A is a schematic diagram of selector equipment for selecting a chassis type.

8B is a schematic diagram of rod position selector equipment in accordance with an embodiment of the present invention.

9A is a schematic diagram of a plurality of measurement positions associated with different rod positions on a truck chassis.

9B is a schematic diagram of a plurality of measurement positions associated with concentrating a rod on different rod positions of a truck chassis.

10 is a schematic diagram illustrating different loading / unloading cycles.

Detailed Description of Embodiments

FIG. 1 shows the case where the ship unloading the crane is seen from behind. A chassis alignment system (CAS) according to one embodiment of the present invention schematically shows that it is installed on a ship that lands a crane. The figure shows a trolley 2, an instruction bar 3, two crane legs 4, 5. CAS 6 appears to be installed on a crane adjacent to a service platform 7 and an access ladder 8. The indicator bar 3 includes five lights, green 3a, green 3b, yellow 3c, red 3d, and yellow 3e in this embodiment. The container 9 appears to be hanging under the crane trolley 2.

The chassis alignment system, CAS 6, has the following two main functions.

Indication to the truck driver when the chassis landing area is aligned with the crane's centerline in the cantree driving direction.

Optionally aligning the spreader to the chassis position in the trolley direction (this feature requires the crane to have an automatic positioning that can be used to follow the criteria from the CAS as described in other embodiments below)

CAS (6) may be contained in a box located in a fixed location outside the girder between the landside and waterside bridges. It uses a 3D laser scanner to measure the position of the truck chassis from a height of about 35m. It is looking for the characteristic edges of the general goal. The installation height is necessary to allow CAS to clearly see the chassis lanes beneath the crane legs. Also, the height allows the CAS to manage all parallel lanes at the same time. Of course, the actual position varies with different crane types depending on the optimum position. Because CAS is based on laser technology, no additional sensors or other equipment need to be installed on the chassis. This also makes the weather independent.

6 shows a schematic diagram for a multi lane region. This figure shows a view from above of the six lanes L1-L6, the chassis with containers from the left 10, the empty chassis 11, the empty chassis from the right 12, the rear beam 15 . Four trapezoidal shapes, including shapes 13 and 14 (shpae) represent scans possible by CAS (6). A scan 13 in the gantry driving direction scans to indicate the stop position of the chassis, which scan is directed towards the middle of the rear beam. The scan 14 is a trolley scan for aligning the trolley position to the chassis 12. The crane appears to be located on the waterside bridge 16 and the landside bridge 17.

The CAS communicates with the truck driver via the color ramp signal 3a-3e of the indicator bar 3 similarly to the traffic light. The light bar indicates whether the driver stops, moves forward or moves backward to reach the actual position for the next container loading / unloading. The crane operator then instructs the CAS what type of work to do and where on the chassis the actual target will be located. To this end, the driver uses different switch settings on the cabin console (in the embodiment described below, it is not possible for CAS to be supplied by ABB and to interface with a control system called ELC (Electronic Load Control)). ELC is an automatic positioning system with sway control and can be used to provide the CAS with the next target position of the crane).

The 3-D laser scanner of the CAS 6 can observe the target at an angle of +/- 30 degrees in both the gantry and trolley directions. The position of the chassis with loaded container 10 is measured at the top of the container. For the empty chassis 11, 12, the gantry position is measured at the center of the rear beam 15 of the chassis and the trolley position is measured in the middle of the chassis on the two I-beams of the chassis structure. . The chassis type serving the crane must be defined and loaded into the CAS target database (otherwise the vehicle will not be properly recognized).

Typically, trucks reach the chassis lanes before the trolleys reach with a hanging load, which means that a CAS 3-D laser scanner clearly sees the chassis and trolleys, and that the load does not interfere with the observation. It means not to. If the chassis is not in place when the trolley arrives, CAS cannot measure or guide late arriving trucks. The CAS then indicates that red and two yellow lights flash on the light bar 3 so that observation is disturbed. The driver of the chassis must then manually align the chassis without assistance from the CAS, or the crane operator must back the trolley to sharpen the observation and allow the CAS to complete its measurements.

Also, if the chassis lanes (L1-L6) to be measured are on the land side of the CAS, the trolley platform and spreader with its rods may obstruct the chassis' observation when the trolley passes the CAS or moves towards the target chassis lane. . Of course, all the idea is that positioning is done before the trolley reaches. Otherwise, there are bottlenecks in other parts of terminal logistics.

To better understand how CAS works, the general sequence of operations is described here.

1. The CAS is ordered from the crane control system to measure the position of the chassis, which includes information on the active lane, lane direction, and chassis type (if different types of chassis are used).

2. CAS indicates a green light that causes the driver to move the chassis into the lane.

3. The CAS continues to check the active chassis lanes of the selected activity, and when it finds the rear part of the chassis, for example the rear beam 15 on the chassis 12, the yellow top like begins to flash. When the chassis is within a fixed distance to the ideal position, the top yellow light is steady. The fixed distance can be set as a parameter.

4. CAS continuously measures the chassis position in the crane direction and indicates a red light when the chassis is within the ideal position window. If the chassis is overtravel, the CAS switches to the bottom yellow light 3e. The bottom yellow light begins to flash when the excess travel is large.

5. The CAS waits until the chassis stops at the ideal position for a fixed time. The fixed time is set by the parameter.

6. The CAS measures the trolley driving direction position of the chassis and provides feedback of the chassis position and height in the trolley and gantry directions to the crane control system (eg relative to the ELC).

A chassis type selector switch is provided in the crane cabin to allow the operator to switch between different types of chassis. The other switch selector chooses where to put the container on the chassis. Three predefined positions, namely front, center, and rear, can be selected from the examples shown.

8A shows a chassis selector switch 20 having three positions to select from for selecting from three different types. 8B shows the load position selector switch 21. Three possible load positions are indicated in the example shown.

The chassis type selector 20 and the position selector 21 are only needed for the put down of containers on the chassis. Upon pickup, CAS is always measured at the top of the container, after which the container's observation does not depend on the type of chassis. The 45ft container can be operated with a spreader in 40ft mode. In this kind of pickup, the CAS measures the length of the container and aligns the spreader towards the center of the container.

9A shows different loading positions for one or two containers loaded on a truck chassis. The following examples show the different positions of the chassis for different work tasks of the crane. Spreader position 30 indicates the position of the crane's spreader upon foot down (or pickup). The measuring point 31 indicates that the measuring point for the pickup is the top of the container. The measurement points in the footdown 15 are indicated by the same number as the rear beam 15 of the chassis shown in FIG. 6 since it is a different view of the same object. A single 40ft rod 32 appears at the center position and twin load 33 appears to have two 20ft container rods at the center position. 20ft rod rear position 34 and 20ft rod front position 35 are shown.

The CAS may position the chassis for footdown in the front, center or rear. However, the CAS must know where to put the containers on the chassis. The position selector (21 in FIG. 8A) makes a selection among front, center and rear.

Similarly, FIG. 9B shows examples of load positions on a 45ft chassis. The figure shows measurement points at spreader position 30, pickup measurement point 31, footdown 15. 45ft center rod 36 and 40ft center rod 37 are shown. The 40ft rear rod rear position 38 and the 40ft rod front position 39 are shown. Typically, CAS positions 40ft containers to the same center position as 45ft containers because 40ft spreaders can hold 45ft or 40ft containers. The 40ft container can be positioned forward, middle or rear with the "position selector" 21.

The absolute position of container position in the chassis at the front, middle, and rear varies between container sizes (20, 40, and 45 ft) and varies between the three types of chassis. Of course, the position of the measuring point behind the chassis 15 also varies between the three types of chassis.

The chassis alignment system CAS 6 receives work instructions from the crane control system. Work instructions are given in different ways depending on the manual or automatic operating ELC. The measuring sequence and start is made from the normal operation of the crane, ie the operator of the crane does not normally need to press a button to start measuring the CAS.

The CAS begins to measure and position the chassis for the next command when the trolley is moving outward relative to the strand side beam to lift and lower the container onto the vessel. The measurement continues until the chassis is in position, which is usually completed before the trolley returns from the ship.

10 schematically illustrates the movement of one or more containers of shashi on the ground or on a vessel. 10 shows the chassis 40, 41, and 42, the ship 43, and the containers 44, 46. In a single cycle, the container 44 moves at once from the chassis 40 to the ship 43. In a dual cycle, the container 45 can be moved from one chassis 41 to another chassis 42 and then to the vessel 43, as shown in the figure.

In manual operation, CAS 6 obtains the destination of the next cycle and whether it is a footdown or pickup from the chassis lane. This information comes from the twistlock position of the spreader and from one switch defining the pickup chassis lanes and the other switch defining the footdown chassis lanes. Two toggle switches define whether the chassis arrives from the left or from the right. Typically, the selection of chassis lanes is done only once for every new ship. If necessary, the CAS may manage the mode lanes and lock and guide the first vehicle to arrive.

In another embodiment, an automatic electronic load control (ELC) operation is used. In the automatic operation mode, the automatic system knows the destination before the next cycle and provides this information to the CAS. Depending on the destination of the next command, the CAS may determine whether to start measuring pickup or putdown on the chassis.

The driver switches by pressing a button: The driver selects the active chassis lanes for container footdown and pickup, respectively, with two switches in the driver's cabin. An additional toggle switch selects whether the chassis will reach the chassis lanes from left or right. Typically, the selection of chassis lanes is done only once for every new ship.

In another embodiment, the signal function performed in the indicator bar 3 driven by five digital external signals from the CAS 6 may be replaced by other signal means or display means. The same function can be performed using, for example, a display device, an LCD display device, a pixel display device, a computer monitor, or the like. Similarly, the installation of the display device can be altered for effective communication to the truck driver, which includes positioning the display means or the slave display means in the truck chassis cap.

Furthermore, while the exemplary embodiments of the invention have been described above, various modifications and changes can be made to the disclosed solutions without departing from the scope of the invention as defined in the appended claims.

Claims (21)

A method of scanning a truck chassis with sensor means and measuring the distance to a point on the truck chassis by the sensor means to align the truck chassis 12 with the required position for the crane, Determining whether to load the container 9 on the truck chassis 12; Processing the scan results to identify one or more straight edges 15 on the target truck chassis; Processing the recognized one or more straight edges to measure the distance between a truck chassis and a fixed point on a crane; And Generating a signal depending on the measured distance. The method of claim 1, Selecting a truck chassis type; Selecting a load location for the truck chassis type; And when the truck chassis is able to proceed in position towards the required position to receive the rod, signaling by a green light (3a) or the like. The method of claim 2, And when the first target is installed on the truck chassis, signaling by a flashing yellow lamp (3c) or the like at the top of the array. The method of claim 3, wherein And when the truck chassis is within a first predetermined distance of the required position, signaling by a steady yellow light (3c) or the like at the top of the array. The method of claim 4, wherein And when the truck chassis is within an ideal window position relative to the desired position, signaling by a red light (3d) or the like. The method of claim 5, And when the truck chassis has moved beyond the ideal position relative to the required position, signaling by a stable yellow light (3e) or the like at the bottom of the array. The method of claim 6, And signaling by a flash yellow light (3e) at the bottom of the array when the truck chassis has moved excessively beyond the ideal window position with respect to the required position. The method of claim 7, wherein And when it is determined that the truck chassis is in the required position, waiting for a predetermined time. The method of claim 8, And after the predetermined time has elapsed, signaling the position of the truck chassis measured in the trolley direction, the gantry direction, and the height to the crane control system. The method of claim 1, Determining whether to unload the container from the truck chassis; Processing the scan results to identify one or more straight edges on top of the container 31; Processing the recognized one or more straight dpt sheets to determine the distance between a container and a fixed point on the crane; And Generating a signal depending on the determined distance. A system for aligning a truck chassis, comprising sensor means for measuring a distance to a truck chassis, a computer recognition system for processing measurements by the sensor means, and a signal lamp array 3 for signaling to a truck driver, And a selector means (20, 21) to enable selection of a predetermined type of truck chassis and a predetermined load position on the chassis. The method of claim 11, The truck chassis selector means (20) is provided with selection means for selecting one of several predetermined types of truck chassis from a plurality of known truck chassis types stored in a computer recognition system. The method of claim 12, The load chassis selecting means 21 comprises a selection means for selecting one of several predetermined load positions available in different types of truck chassis from a plurality of known load positions stored in a computer recognition system. Sorting system. The method of claim 11, And the sensor means is a 3-D laser camera. The method of claim 11, And the sensor means comprise a Class A laser. The method of claim 11, The alignment system of the truck chassis, characterized in that the signal lamp array (3) for signaling to the driver comprises signal display means. Use of a system according to any of claims 11 to 16, providing a measurement signal to provide a measurement signal for loading a container at a pre-selectable load position, such as the front, middle, or rear load position of the truck chassis. . Use of a system according to any of claims 11 to 16, providing a measurement signal to provide a measurement signal for unloading a container from a preselectable load position, such as the front, middle or rear load position of the truck chassis. . Computer program code element comprising computer code means or software code portion for enabling a computer or processor to perform one or more of a series of instructions according to any one of claims 1 to 10. . A computer program comprising computer program code means for enabling a computer or processor to perform the steps according to any one of claims 1 to 10 and at least partly included in a computer readable medium. Signal for aligning the truck chassis to the required position for the crane implemented in the control signal containing information about the distance between the truck chassis and the fixed point.