CN103863946A - Method for detecting load swinging angle of crane - Google Patents

Abstract

The invention discloses a method for detecting a load swinging angle of a crane. A hoisting hook or a load is connected to a mobile trolley of a crane body through a hoisting rope; more than two wireless network fixing nodes are arranged on the crane body; a wireless network swinging node is arranged on the hoisting hook or the load and respectively communicates with all fixed nodes; the hoisting hook or the load can be spatially positioned on the basis of an RSSI (received signal strength indicator) distance measuring technology; finally, a spatial swinging angle of the load is calculated. The wireless network nodes adopted in the method disclosed by the invention have the advantages of low cost and convenience in installation, and the swinging situation of the load of the crane can be effectively detected, so that the crane can be safely and efficiently produced.

Description

A kind of crane load pivot angle method of inspection

Technical field

The present invention relates to a kind of crane load pivot angle method of inspection, relate to automatic control, wireless communication technology.

Background technology

Along with economic society development, crane is more and more essential in each engineering item as a kind of transportation means, and building site (as subway, high building), harbour and warehouse dispatching can be seen its figure.Its radical function is to utilize hawser to promote and moving heavy object, and replacing rigid body operational advantages by the flexibility of this class of hawser is that the work of crane mechanism is light, and efficiency is also improved; Shortcoming is in the time that crane promotes or transfers load in moving process, and the situation such as wind, friction occurring in this process, can make load swing back and forth, when amplitude of fluctuation exceedes certain limit, and the major accident such as may cause that load is fallen.Therefore will carry out anti-sway control to load, this will seek knowledge and load on the pivot angle information in space.

At present also more rare at the device of crane pivot angle detection field, existing method of measurement has:

Directly measure: in Chinese patent 200910166488.4, " a kind of hoisting crane and lifting rope swing angle detection device thereof ", proposition at least utilizes an angular transducer and the sleeve outside suit and lifting rope coaxially.

Indirectly measure: the Li Wei of Shandong University Building proposes, undertaken processing and measuring pivot angle in real time by the load digital image of fixed cameras and image pick-up card collection.

Summary of the invention

Goal of the invention: in order to overcome the deficiencies in the prior art, the invention provides a kind of crane load pivot angle method of inspection, can indirectly measure crane load pivot angle, not high to environmental requirement, be easy to realize; Be used in the scheme that suppresses suspension hook or hunting of load in crane work, make to swing quick decay and even eliminate, such as the automatic anti-swinging for realizing crane work, to improve the safety of crane work.

Technical scheme: for achieving the above object, the technical solution used in the present invention is:

A kind of crane load pivot angle method of inspection, suspension hook/load is connected on the travelling car of crane body by lifting rope, and more than two wireless network stationary nodes is installed on crane body, a wireless network is installed in suspension hook/load and swings node; Swing node and intercom mutually with all stationary nodes respectively, realize the location, locus of suspension hook/load based on received signal strength index RSSI ranging technology, finally calculate the space pivot angle of load.

Said method specifically comprises the steps:

(1) stationary nodes/swing node continues outwards stably to send network signal;

(2) swing node/stationary nodes and receive in real time and process the network signal from stationary nodes/swing node, according to the power that receives signal, utilize RSSI ranging technology to obtain swinging the distance between node and stationary nodes;

(3) distance according to the swing node calculating and between fixing, swing node and the installation site of stationary nodes and the basic operating conditions of crane, through calculating the space pivot angle of suspension hook/load.

The most basic design, described stationary nodes number is two, swinging node number is one; If α is the amplitude size that suspension hook/load space swings, β is the direction size that suspension hook/load space swings, and can set up two equations about unknown number α and β, obtains the space pivot angle of suspension hook/load by solving equation group.

It is more than three can also designing described stationary nodes number, and swinging node number is one; If α is the amplitude size that suspension hook/load space swings, β is the direction size that suspension hook/load space swings, can set up three above equations about unknown number α and β, obtain the space pivot angle of suspension hook/load by optimized algorithm (such as method of least square etc.).

Described wireless network node (comprise stationary nodes and swing node), can refer to comprise ZigBee wireless network node at interior, ripe, any wireless network node cheaply.

Beneficial effect: crane load pivot angle method of inspection provided by the invention, compared to prior art, tool has the following advantages: 1, adopt wireless network node to detect, detect low in energy consumption and volume is little, be convenient to be arranged on suspension hook/load and crane body; 2, the communication between wireless network node carries out based on wireless network communication mode, does not need peripheral wiring, has both reduced cost, very convenient again; 3, to testing environment require lowly, comformability is high.

Brief description of the drawings

Fig. 1 is the overhaul flow chart of the inventive method;

Fig. 2 is that schematic diagram is arranged and detected to a kind of wireless network node of the present invention;

Fig. 3 is wireless network node and overhead crane control case process chart.

Detailed description of the invention

Below in conjunction with accompanying drawing, the present invention is further described.

A kind of crane load pivot angle method of inspection, suspension hook/load is connected on the travelling car of crane body by lifting rope, and more than two wireless network stationary nodes is installed on crane body, a wireless network is installed in suspension hook/load and swings node; Swing node and intercom mutually with all stationary nodes respectively, realize the location, locus of suspension hook/load based on received signal strength index RSSI ranging technology, finally calculate the space pivot angle of load.

As shown in Figure 1, said method specifically comprises the steps:

(1) stationary nodes/swing node continues outwards stably to send network signal;

(2) swing node/stationary nodes and receive in real time and process the network signal from stationary nodes/swing node, according to the power that receives signal, utilize RSSI ranging technology to obtain swinging the distance between node and stationary nodes;

(3) distance according to the swing node calculating and between fixing, swing node and the installation site of stationary nodes and the basic operating conditions of crane, through calculating the space pivot angle of suspension hook/load.

The most basic design, described stationary nodes number is two, the number that swings node is one; If α is the amplitude size that suspension hook/load space swings, β is the direction size that suspension hook/load space swings, and can set up two equations about unknown number α and β, obtains the space pivot angle of suspension hook/load by solving equation group.

It is more than three can also designing described stationary nodes number, and the number that swings node is one; If α is the amplitude size that suspension hook/load space swings, β is the direction size that suspension hook/load space swings, and can set up three above equations about unknown number α and β, obtains the space pivot angle of suspension hook/load by optimized algorithm.Many design sensor nodes, can improve final survey precision by optimized algorithm.

Described wireless network node (comprise stationary nodes and swing node), can refer to comprise ZigBee wireless network node at interior, ripe, any wireless network node cheaply.

Below in conjunction with example, the present invention is made further instructions.

As shown in Figure 2, for a kind of system of measuring crane load space pivot angle, comprise the first wireless network node 1, second wireless network node 2, the 3rd wireless network node 3, the 4th wireless network node 4, the 5th wireless network node 5, crane body 6, lifting rope 7, load 8, overhead crane control case 9, suspension hook 10 and moveable carriage 11; Lifting rope 7 can stretch up and down, and can be along sway under the traction of moveable carriage 11; Overhead crane control case 9 is fixed on crane body 6, contains similar wireless communication function in overhead crane control case 9; The first wireless network node 1, as swinging node of network, is arranged on suspension hook 10 or in load 8; Second wireless network node 2, the 3rd wireless network node 3, the 4th wireless network node 4 and the 5th node of network 5, be fixed on as shown in Figure 2 on crane body 6, as stationary nodes, wherein the minimum number of stationary nodes is two, also can, more than 4, in figure, only mark out four.Finally needing the amount obtaining is the pendulum angle that crane loads on space, and α is as shown in Figure 2 the amplitude size that suspension hook/load space swings, and β is the direction size that suspension hook/load space swings.

In this case, swing node and the installation site of stationary nodes and the basic operating conditions of crane as shown in Figure 2, be specially: the distance of moveable carriage sway on crane is that the height of x, crane itself is that distance between h, crane fulcrum B and fulcrum D is that distance between l, fulcrum D and fulcrum C is d, and lifting rope length is r; These are known quantity.Distance s between node ₁, s ₂and s ₃for to be measured.α and β are load space pivot angle to be asked.The distance parameter s measuring ₁, s ₂and s ₃can be transferred to overhead crane control case by wireless communication mode, carry out the calculating of load space pivot angle by overhead crane control case.

As shown in Figure 2, taking O point as the origin of coordinates (0,0,0), B point coordinate is (0 ,-d/2,0), and C point coordinate is (l, d/2,0), and D point coordinate is (l ,-d/2,0).In two kinds of situation the numerical procedure of load space pivot angle is provided to explanation below.

Situation one: only have two stationary nodes and a swing node, distance parameter only has s ₁and s ₂situation

Because x is known quantity, geometric relationship in 1 with reference to the accompanying drawings, A point coordinate can be expressed as (x+rsin α sin β, rsin α cos β, h-rcos α), because s ₁, s ₂can be measured by RSSI ranging technology, therefore can be regarded as known conditions.

According to the range formula between 2 o'clock $d=\sqrt{{(x_1-x_2)}^2+{(y_1-y_2)}^2+{(z_1-z_2)}^2},$ In formula, d is a M(x ₁, y ₁, z ₁) and some N(x ₂, y ₂, z ₂) between distance.

Distance between calculation level AB is:

$s_1=\sqrt{{(x+r\sin \mathrm{\α}\sin \mathrm{\β})}^2+{(r\sin \mathrm{\α}\cos \mathrm{\β}+\frac{d}{2})}^2+{(h-r\cos \mathrm{\α})}^2}$

Distance between calculation level AC is:

$s_2=\sqrt{{(x+r\sin \mathrm{\α}\sin \mathrm{\β}-l)}^2+{(r\sin \mathrm{\α}\cos \mathrm{\β}-\frac{d}{2})}^2+{(h-r\cos \mathrm{\α})}^2}$

In above two formulas, only having α and β is unknown number, and now two unknown numberes of two equations, can solve α and β by solving equation group.Solve:

$\left\{\begin{array}{c}\mathrm{\α}=g_1(s_1,s_2,x,r,l,h,d)\\ \mathrm{\β}=g_2(s_1,s_2,x,r,l,h,d)\end{array}\right.$

Situation two: have n-1 stationary nodes and a swing node, distance parameter has s ₁, s ₂, s ₃... s _n-1situation, wherein n>=4

If stationary nodes is M ₁, M ₂..., M _n-1, there is distance in each like this stationary nodes and swing node, is respectively s ₁, s ₂, s ₃... s _n-1, can be expressed as:

$\left\{\begin{array}{c}{s}_1=\left|{\mathrm{AM}}_1\right|=f({\mathrm{\α}}_1,{\mathrm{\β}}_1)\\ s_2=\left|{\mathrm{AM}}_2\right|=f({\mathrm{\α}}_2,{\mathrm{\β}}_2)\\ \·\·\·\\ s_{n-1}=\left|{\mathrm{AM}}_{n-1}\right|=f({\mathrm{\α}}_{n-1},{\mathrm{\β}}_{n-1})\end{array}\right.$

Now occur multiple equations, but unknown number is still two, now the number of set of equations, more than unknown number number, can, by obtaining optimal solution as optimization methods such as method of least square, can be expressed as α ^*, β ^*.

Figure 3 shows that the work schematic diagram of wireless network node and overhead crane control case 9, the wireless network node being arranged on load 8 or suspension hook 10 receives the signal of communication sending from the wireless network node being arranged on crane body 6 in real time, measures the distance s of (RSSI telemetry) node according to the attenuation of signal ₁, s ₂, s ₃... s _n-1, then by distance parameter s ₁, s ₂, s ₃... s _n-1to overhead crane control case 9, by resolving module and directly obtain space pivot angle parameter alpha and the β of load 8 or suspension hook 10 wherein, or by being optimized, pivot angle obtains optimal solution α through wireless way for transmitting ^*and β ^*; In overhead crane control case 9, anti-sway control module is carried out hunting of load monitoring and anti-sway control according to the pivot angle information of calculating gained.

The above is only the preferred embodiment of the present invention; be noted that for those skilled in the art; under the premise without departing from the principles of the invention, can also make some improvements and modifications, these improvements and modifications also should be considered as protection scope of the present invention.

Claims (4)

1. a crane load pivot angle method of inspection, it is characterized in that: suspension hook/load is connected on the travelling car of crane body by lifting rope, more than two wireless network stationary nodes is installed on crane body, a wireless network is installed in suspension hook/load and swings node; Swing node and intercom mutually with all stationary nodes respectively, realize the location, locus of suspension hook/load based on received signal strength index RSSI ranging technology, finally calculate the space pivot angle of load.

2. crane load pivot angle method of inspection according to claim 1, is characterized in that: comprise the steps:

(1) stationary nodes/swing node continues outwards stably to send network signal;

(2) swing node/stationary nodes and receive in real time and process the network signal from stationary nodes/swing node, according to the power that receives signal, utilize RSSI ranging technology to obtain swinging the distance between node and stationary nodes;

(3) distance according to the swing node calculating and between fixing, swing node and the installation site of stationary nodes and the basic operating conditions of crane, through calculating the space pivot angle of suspension hook/load.

3. crane load pivot angle method of inspection according to claim 1, is characterized in that: described stationary nodes number is two, and swinging node number is one; If α is the amplitude size that suspension hook/load space swings, β is the direction size that suspension hook/load space swings, and can set up two equations about unknown number α and β, obtains the space pivot angle of suspension hook/load by solving equation group.

4. crane load pivot angle method of inspection according to claim 1, is characterized in that: described stationary nodes number is more than three, and swinging node number is one; If α is the amplitude size that suspension hook/load space swings, β is the direction size that suspension hook/load space swings, and can set up three above equations about unknown number α and β, obtains the space pivot angle of suspension hook/load by optimized algorithm.

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