CN103863946B

CN103863946B - A kind of crane load pivot angle detection method

Info

Publication number: CN103863946B
Application number: CN201410118160.6A
Authority: CN
Inventors: 高丙团; 张罗马; 魏巍; 郎伊紫禾; 黄博然
Original assignee: Southeast University
Current assignee: Southeast University
Priority date: 2014-03-26
Filing date: 2014-03-26
Publication date: 2016-06-29
Anticipated expiration: 2034-03-26
Also published as: CN103863946A

Abstract

The invention discloses a kind of crane load pivot angle detection method, suspension hook/load is connected on the travelling car of crane body by lifting rope, crane body is provided with two or more wireless network stationary nodes, suspension hook/load is provided with a wireless network and swings node；Swing node to 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.Wireless network node involved in the present invention has the advantage that low cost is easy for installation, can effectively detect the swing situation of crane load, thus being of value to the safe and efficient production of crane.

Description

A kind of crane load pivot angle detection method

Technical field

The present invention relates to a kind of crane load pivot angle detection method, relate to automatically controlling, wireless communication technology.

Background technology

Along with economic society development, crane as a kind of means of transport in each engineering project more and more essential, building site (such as subway, high building), harbour and warehouse dispatching can see its figure.Its major function is to utilize hawser to promote and moving heavy object, replaces rigid body operational advantages to be that the work of crane mechanism is light by the flexibility that hawser is this kind of, and efficiency is also improved；Shortcoming is when crane promotes or during lowering loads in moving process, and the situation such as the wind occurred in the process, friction, load can be made to swing back and forth, when amplitude of fluctuation exceedes certain limit, it is possible to the major accident such as can cause that load is fallen.Therefore load is carried out anti-swing control, this load pivot angle information in space of will seeking knowledge.

Also more rare at the device of crane pivot angle detection field at present, existing measuring method has:

Directly measure: Chinese patent 200910166488.4, " a kind of crane and lifting rope swing angle detection device thereof " propose at least with an angular transducer and is set with the sleeve outside with lifting rope coaxially.

Indirectly measure: Shandong University Building Li Wei proposes, undertaken processing in real time measuring pivot angle by the load digital picture of fixing video camera 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 present invention does not provide a kind of crane load pivot angle detection method, it is possible to indirectly measure crane load pivot angle, environmental requirement is high, be easily achieved；Can be used in the scheme of suppression suspension hook or hunting of load, making swing rapid decay even eliminate in crane works, such as realizing the automatic anti-swinging in 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 detection method, suspension hook/load is connected on the travelling car of crane body by lifting rope, is provided with two or more wireless network stationary nodes on crane body, is provided with a wireless network and swings node in suspension hook/load；Swing node to 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 includes following steps:

(1) stationary nodes/swing node persistently outwards stably sends network signal；

(2) swing node/stationary nodes real-time reception and process the network signal from stationary nodes/swing node, according to the power receiving signal, utilizing RSSI ranging technology to obtain swinging the distance between node and stationary nodes；

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

Most basic design, 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, then can set up two equations about unknown number α and β, be obtained the space pivot angle of suspension hook/load by solving equation group.

Can also design 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, then can set up three equations above with respect to unknown number α and β, be obtained the space pivot angle of suspension hook/load by optimized algorithm (such as method of least square etc.).

Described wireless network node (includes stationary nodes and swings node), it is possible to refer to comprise ZigBee wireless network node, any wireless network node ripe, low cost.

Beneficial effect: crane load pivot angle detection method provided by the invention, compared to prior art, has the advantage that 1, adopts wireless network node to detect, detect low in energy consumption and volume is little, it is simple to be arranged on suspension hook/load and crane body；2, the information transmission between wireless network node carries out based on wireless network communication mode, it is not necessary to peripheral wiring, has both decreased cost, very convenient again；3, the requirement of detection environment is low, adaptability is high.

Accompanying drawing explanation

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

A kind of wireless network node that Fig. 2 is the present invention is arranged and detection schematic diagram；

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.

As it is shown in figure 1, said method specifically includes following steps:

Most basic design, described stationary nodes number is two, and the number swinging 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, then can set up two equations about unknown number α and β, be obtained the space pivot angle of suspension hook/load by solving equation group.

Can also design described stationary nodes number is more than three, and the number swinging 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, then can set up three equations above with respect to unknown number α and β, be obtained the space pivot angle of suspension hook/load by optimized algorithm.Design sensor node, it is possible to improve final certainty of measurement by optimized algorithm more.

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

As shown in Figure 2, for a kind of system measuring crane load space pivot angle, including the first wireless network node 1, second wireless network node the 2, the 3rd wireless network node the 3, the 4th wireless network node the 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 along moving left and right under the traction of moveable carriage 11；Overhead crane control case 9 is fixed on crane body 6, containing similar wireless communication function in overhead crane control case 9；First wireless network node 1, as swinging network node, is arranged on suspension hook 10 or in load 8；Second wireless network node the 2, the 3rd wireless network node the 3, the 4th wireless network node 4 and the 5th network node 5, being fixed on crane body 6 as shown in Figure 2, as stationary nodes, wherein the minimum number of stationary nodes is two, also more than 4, figure can only mark out four.The final amount needing to obtain is the crane load pendulum angle in space, and namely α as shown in Figure 2 is the amplitude size that suspension hook/load space swings, and β is the direction size that suspension hook/load space swings.

In this case, the installation site of swing node and stationary nodes and the basic operating conditions of crane are as shown in Figure 2, particularly as follows: the distance that moveable carriage moves left and right on crane be x, crane itself height be h, distance between crane fulcrum B and fulcrum D be the distance between l, fulcrum D and fulcrum C be d, lifting rope length is r；These are known quantity.Distance s between node₁, s₂And s₃For to be measured.α and β is load space pivot angle to be asked.The distance parameter s measured₁, s₂And s₃Overhead crane control case can be transferred to by wireless communication mode, be carried out the calculating of load space pivot angle by overhead crane control case.

As in figure 2 it is shown, with O point for zero (0,0,0), then B point coordinates is (0 ,-d/2,0), and C point coordinates is (l, d/2,0), and D point coordinates is (l ,-d/2,0).In two kinds of situation the numerical procedure of load space pivot angle is provided explanation below.

Situation one: only existing two stationary nodes and a swing node, namely distance parameter only has s₁And s₂Situation

Because x is known quantity, geometrical relationship in 1 with reference to the accompanying drawings, then A point coordinates is represented by (x+rsin α sin β, rsin α cos β, h-rcos α), because s₁,s₂Can 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(x₁,y₁,z₁) and some N(x₂,y₂,z₂) between distance.

The distance calculated between some AB is:

s_{1} = \sqrt{{(x + r \sin α \sin β)}^{2} + {(r \sin α \cos β + \frac{d}{2})}^{2} + {(h - r \cos α)}^{2}}

The distance calculated between some AC is:

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

In above two formulas, only α and β is unknown number, and now two unknown numbers of two equations, can be solved α and β by solving equation group.Namely solve:

\{\begin{matrix} α = g_{1} (s_{1}, s_{2}, x, r, l, h, d) \\ β = g_{2} (s_{1}, s_{2}, x, r, l, h, d) \end{matrix}

Situation two: there is n-1 stationary nodes and a swing node, namely distance parameter has s₁,s₂,s₃,...s_n-1Situation, wherein n >=4

If stationary nodes is M₁, M₂..., M_n-1, there is distance in so each stationary nodes and swing node, respectively s₁,s₂,s₃,...s_n-1, it is possible to it is expressed as:

\{\begin{matrix} s_{1} = | {AM}_{1} | = f (α_{1}, β_{1}) \\ s_{2} = | {AM}_{2} | = f (α_{2}, β_{2}) \\ \cdot \cdot \cdot \\ s_{n - 1} = | {AM}_{n - 1} | = f (α_{n - 1}, β_{n - 1}) \end{matrix}

Multiple equation now occur, but unknown number remains as two, now the number of equation group is more than unknown number number, it is possible to obtains optimal solution by optimization methods such as such as method of least square, is represented by α^*, β^*。

Fig. 3 show wireless network node and the operating diagram of overhead crane control case 9, the signal of communication that the wireless network node real-time reception being arranged on load 8 or suspension hook 10 sends from the wireless network node being arranged on crane body 6, measures the distance s of (RSSI telemetry) node according to the attenuation of signal₁,s₂,s₃,...s_n-1, then by distance parameter s₁,s₂,s₃,...s_n-1Through wireless way for transmitting to overhead crane control case 9, directly obtained space pivot angle parameter alpha and the β of load 8 or suspension hook 10 by resolving module therein, or obtain optimal solution α by pivot angle is optimized^*And β^*；In overhead crane control case 9, anti-swing control module carries out hunting of load monitoring and anti-swing control according to the pivot angle information calculating gained.

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

Claims

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

(1) stationary nodes or swing node persistently outwards stably send network signal；

(2) if stationary nodes persistently outwards stably sends network signal, then by swinging node real-time reception and processing the network signal from stationary nodes；If swinging node persistently outwards stably send network signal, then by stationary nodes real-time reception the network signal processing self-swinging node；According to the power receiving signal, RSSI ranging technology is utilized to obtain swinging the distance between node and stationary nodes；

(3) according to the basic operating conditions of the distance swung between node and stationary nodes calculated, the installation site swinging node and stationary nodes and crane, through calculating the space pivot angle obtaining suspension hook or load.

2. crane load pivot angle detection method according to claim 1, it is characterised in that: described stationary nodes number is two, and swinging node number is one；If α is suspension hook or the amplitude size of load space swing, β is suspension hook or the direction size of load space swing, then can set up two equations about unknown number α and β, be obtained the space pivot angle of suspension hook or load by solving equation group.

3. crane load pivot angle detection method according to claim 1, it is characterised in that: described stationary nodes number is more than three, and swinging node number is one；If α is suspension hook or the amplitude size of load space swing, β is suspension hook or the direction size of load space swing, then can set up three equations above with respect to unknown number α and β, be obtained the space pivot angle of suspension hook or load by optimized algorithm.