CN101349606A - Method for dynamically detecting carriage trucks mass center height - Google Patents

Abstract

The invention relates to a dynamic detection method of the mass center height of a freight car, which comprises the following steps, firstly, being provided with a dynamic detection device of the mass center height of a freight car, and the dynamic detection device comprises a steering wheel rotating angle measuring device, a transverse-swing angular speed measuring device, a slope angle measuring device and an electronic control unit which comprises a singlechip, a solidification program in the singlechip is provided with a dynamic detection algorithm module of the mass center height, secondly, colleting rotating angle signals of the steering wheel, transverse-swing angular speed signals of a freight car along the vertical direction, heeling angle signals of a boxcar, heeling angle signals of the rear shaft of a freight car and longitudinal vehicle speed signals of a freight car, thirdly, calculating the mass center height of a freight car through the dynamic detection algorithm module of the mass center height. The dynamic detection method can automatically and safely control a freight car through software to calculate out the maximum limiting speed of side tumbling of a freight car and through the mode of reminding a driver to decelerate or automatically enforcing to brake according to the mass center height which is calculated out in time, and can avoid traffic accidents from happening. The dynamic detection method of the mass center height of a freight car can be widely applied in the driving safety control process of various freight cars.

Description

Dynamic detection method of barycenter height of truck

Technical field

The present invention relates to a kind of lorry method for safety monitoring, particularly about a kind of dynamic detection method of barycenter height of truck.

Background technology

Lorry is when shipping goods, and because of the kind of its lade with vary in weight, its height of center of mass changes often.If height of center of mass is higher, the speed of a motor vehicle is very fast, lorry is easy to take place the rollover accident when negotiation of bends, cause great casualties and property loss.Thus, actively developing the security of operation and the monitoring technique of research lorry both at home and abroad, for example the intelligent vehicle speed system promptly realizes the control automatically of car speed ground according to road conditions and vehicle performance parameter, thereby makes vehicle can pass through bend safely; Again such as the safety control technology of coordinating based on bus or train route, by bus or train route communication information, trailer-mounted radar information, state of motion of vehicle information etc., the security of operation state of real-time judge vehicle utilizes on-vehicle safety actuating unit such as electronics complemental brake system that vehicle can be moved with the speed of safety.For these safety techniques, vehicle self performance parameter is to set up the basis of correct security control algorithm, and the height of center of mass of vehicle is one of of paramount importance parameter in these parameters, can the identification to the vehicle height of center of mass then be the key that finally realize vehicle safety control, so significant to the dynamic monitoring of vehicle height of center of mass.

Detection technique to barycenter height of truck mainly is to utilize instruments such as weighing instrument, tape measure, inclinometer that barycenter height of truck is carried out static measurement at present, promptly must when lorry is still on the instrument of weighing, could measure, and when truckload and type of merchandize variation, also must repeat said process and just can obtain its new height of center of mass its height of center of mass.Therefore, for the detection technique of present barycenter height of truck, mainly there is following problem: the first, because the type of merchandize and the weight of charge of trucks change often, so existing detection technique does not have specific aim, when changing, the goods that loads just is difficult to know its actual height of center of mass; The second, the detected barycenter height of truck of prior art be difficult to guarantee its real-time accuracy, thereby causes the vehicle safety control algolithm set up based on this height of center of mass inaccurate, therefore can't effectively ensure lorry on bend safe operation.

Summary of the invention

At the problems referred to above, the purpose of this invention is to provide a kind of dynamic detection method of barycenter height of truck that can in the lorry driving process, in real time, accurately detect its height of center of mass.

For achieving the above object, the present invention takes following technical scheme: a kind of dynamic detection method of barycenter height of truck, it may further comprise the steps: 1) a barycenter height of truck device for dynamically detecting is set, and it comprises steering wheel angle measurement mechanism, yaw velocity measurement mechanism, dip measuring device and includes the electronic control unit of single-chip microcomputer; Program curing in the described single-chip microcomputer is provided with the height of center of mass dynamic detection algorithm module; 2) gather the steering wheel angle signal, lorry is along vertical yaw velocity signal, the side tilt angle signal of boxcar, the side tilt angle signal of lorry rear axle, vertical vehicle speed signal of lorry; 3) by described height of center of mass dynamic detection algorithm module, calculate barycenter height of truck.

The calculating formula of described barycenter height of truck is as follows:

${\mathrm{\&omega;}}_{\mathrm{rs}}\left(k\right)=\frac{u\left(k\right)/\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="A20081011968300111.png"\; state="\{\{state\}\}">L</figure-callout>}}{1+\mathrm{Cu}{\left(k\right)}^2}\mathrm{\&delta;}\left(k\right)$

${\widehat{\mathrm{\&omega;}}}_r\left(k\right)=(1-\mathrm{\&lambda;}){\mathrm{\&omega;}}_{\mathrm{rm}}\left(k\right)+\mathrm{\&lambda;}{\mathrm{\&omega;}}_{\mathrm{rs}}\left(k\right)$

${\hat{a}}_y\left(k\right)=u\left(k\right)\&CenterDot;{\widehat{\mathrm{\&omega;}}}_r\left(k\right)$

H(k)＝H(k-1)+Q(k)e(k)

In the formula, k represents k step sampling instant, ω _Rs(k) be the theoretical stable state yaw velocity of lorry signal, u (k) is the lorry vehicle speed signal, and L is the lorry wheelbase, and δ (k) is the steering wheel angle signal, and C is the stable factor of lorry, For proofreading and correct the stable state yaw velocity, λ is a weight coefficient, ω _Rm(k) be yaw velocity,

Be the lorry side acceleration, g is an acceleration of gravity, and H (k) is a k barycenter height of truck constantly, and e (k) is a k-1 evaluated error constantly,

Be the roll angular rigidity of lorry suspension,

Be the side tilt angle signal of boxcar,

Be the side tilt angle signal of lorry rear axle, H (k-1) is a k-1 barycenter height of truck constantly, h _aBe the height on bottom, boxcar to road surface, m is the lorry quality, and Q (k) is a gain matrix, and P (k-1) is a k-1 matrix poised for battle constantly, and ε is a forgetting factor, and P (k) is a k matrix poised for battle constantly.

The present invention is owing to take above technical scheme, it has the following advantages: 1, the present invention is according to the difference of truckload goods, the curvature difference of bend, the principle that the height of center of mass of lorry is also different, the Real-time and Dynamic Detection barycenter height of truck has been proposed, to realize mode to max. speed control.2, the present invention gathers the various kinetic parameters of lorry in real time by the pick-up unit that is arranged on the lorry, and by the dynamic detection algorithm module that is arranged in the single-chip microcomputer height of center of mass is calculated, therefore can obtain accurate barycenter height of truck in real time.3, the present invention can be according to the height of center of mass that calculates in real time, go out the Maximum speed limit of lorry rollover by computed in software, therefore not only can control the generation of rollover accident by the mode of reminding the driver to slow down, and can be by complemental brake system (such as vacuum booster and electro-hydraulic complemental brake system etc.) is set, the automatic mode of braking by force, realization is to the automatic safe control of lorry, the generation that avoids traffic accident.4, the measurement mechanism that uses of the inventive method and control module adopt basically all is existing equipment in the vehicle safety control, need add extra measurement mechanism hardly to the detection of vehicle height of center of mass.The present invention can be widely used in the traffic safety control procedure of various lorries.

Description of drawings

Fig. 1 is a structured flowchart of the present invention

Fig. 2 is a dip measuring device of the present invention installation site synoptic diagram

Fig. 3 is the circuit theory diagrams of electronic control unit of the present invention

Embodiment

Below in conjunction with drawings and Examples the present invention is described in detail.

The inventive method may further comprise the steps:

1) as shown in Figure 1, one barycenter height of truck device for dynamically detecting is set, and it comprises steering wheel angle measurement mechanism 1, yaw velocity measurement mechanism 2, dip measuring device 3 and includes the electronic control unit of single-chip microcomputer U1 (Electronic Control Unit) ECU4; Program curing in the single-chip microcomputer U1 is provided with the height of center of mass dynamic detection algorithm module.

2) gather the steering wheel angle signal, lorry is along vertical yaw velocity signal, the side tilt angle signal of boxcar, the side tilt angle signal of lorry rear axle, vertical vehicle speed signal of lorry.

3) by the height of center of mass dynamic detection algorithm module, calculate barycenter height of truck.

Step 1) and 2) in, steering wheel angle measurement mechanism 1 adopts a steering wheel angle sensor, it is fixedly installed on the steering column of lorry bearing circle below, it is used to detect the bearing circle angular signal and flows to ECU4, and the signal that flows to ECU4 is the two-way analog voltage signal, one the tunnel is used to judge the direction and the number of turns that bearing circle rotates, and another road is used to the angle of judging that bearing circle is turned in this circle.In the present embodiment, steering wheel angle sensor is the LH3-SX-4300A type rotary angle transmitter of BI company, maximum input voltage is 16V, range is-900 °～+ 900 °, impulsive force that can anti-10g, be applicable to vehicle environment, steering wheel angle measurement mechanism 1 also can be taked various types of sensors, and its installation site also can change.

Step 1) and 2) in, yaw velocity measurement mechanism 2 adopts a yaw-rate sensor, it is installed on the infall of two axis, bottom, boxcar, it is used to detect lorry along vertical yaw velocity signal and flow to ECU4, and the signal that flows to ECU4 is the analog voltage signal that changes between 0～5V.In the present embodiment, yaw-rate sensor adopts the LCG50-00100-100 type sensor of BEI company, and specified input voltage is 5Vdc, and range is ± 100 °/s, satisfies the lorry request for utilization, but the type of yaw velocity measurement mechanism 2 is not limited thereto.

As shown in Figure 2, step 1) and 2) in, dip measuring device 3 adopts two inclinators 31,32, wherein inclinator 31 is installed in the place, point of crossing of boxcar bottom longitudinal central axis line and the projection of rear axle on the compartment, inclinator 32 is installed in the midpoint of rear axle, is respectively applied for the side tilt angle that detects the boxcar

Side tilt angle with the lorry rear axle

Signal, output signal

With

Be digital signal, can flow to ECU4 by the serial ports on the inclinator 31,32.In the present embodiment, two inclinators 31,32 adopt the LAM-TD-45D type single shaft obliquity sensor of Lamshine company, it is built-in with temperature compensation and impacts and suppress module, be applicable to vehicle environment, but wherein arbitrary inclinator can adopt also two displacement transducers to replace.

As shown in Figure 3, step 1) and 2) in, ECU4 comprises a single-chip microcomputer U1 and related peripheral circuit, single-chip microcomputer U1 has three road A/D change-over circuits, and inside is provided with a height of center of mass dynamic detection algorithm module, its analog voltage signal with steering wheel angle measurement mechanism 1 and 2 outputs of yaw velocity measurement mechanism converts digital signal to, receive the digital signal that dip measuring device 3 is carried simultaneously, and according to detected lorry dynamics basic parameter information, and algorithm computation lorry side acceleration and height of center of mass in the theoretical operation of the automobile dynamics barycenter height of truck dynamic detection algorithm module.In the present embodiment, it is the 8-bit microcontroller of MC9S08DZ60 that the single-chip microcomputer U1 among the EUC4 adopts Motorola Inc.'s production, model, also can adopt other similar single-chip microcomputer, does not limit at this.

As shown in Figure 3, step 1) and 2) in, ECU4 also comprises three tunnel filtering noise reducing circuits of end difference closure 1 liang of output terminal of dish corner measuring apparatus and yaw velocity measurement mechanism 2 output terminals, and its other end connects input end ADIN0, ADIN1 and the ADIN2 of three road A/D change-over circuits of single-chip microcomputer U1 among the ECU4 respectively.What first via filtering noise reducing circuit was imported is the bearing circle rotation direction of steering wheel angle sensor 1 output and the signal of the number of turns, this circuit is made up of capacitor C 11, C12 and resistance R 1, capacitor C 12 is with after resistance R 1 is connected, and the series arm that obtains is in parallel with capacitor C 11; One termination ground wire of this parallel circuit, the other end connect the input end ADIN0 of first via A/D change-over circuit and the anode of a diode D1 simultaneously, and the negative electrode of diode D1 connects supply voltage VCC; What the second tunnel filtering noise reducing circuit was imported is the signal of steering wheel angle measurement mechanism 1 outbound course dish angle that turns in this circle, this circuit is made up of capacitor C 13, C14 and resistance R 2, capacitor C 14 is with after resistance R 2 is connected, and the series arm that obtains is in parallel with capacitor C 13; One termination ground wire of this parallel circuit, the other end connect the input end ADIN1 of the second road A/D change-over circuit and the anode of a diode D2 simultaneously, and the negative electrode of diode D2 connects supply voltage VCC; Third Road filtering noise reducing circuit input be the signal of yaw velocity measurement mechanism 2 outputs, this circuit is made up of capacitor C 15, C16 and resistance R 3, capacitor C 16 is with after resistance R 3 is connected, the series arm that obtains is in parallel with capacitor C 15; One termination ground wire of this parallel circuit, the other end connect the input end ADIN2 of Third Road A/D change-over circuit and the anode of a diode D3 simultaneously, and the negative electrode of diode D3 connects supply voltage VCC.The filtering noise reducing circuit is used for filtering the high frequency noise of simulating signal, to prevent in follow-up A/D sampling process signal aliasing taking place.The filtering noise reducing circuit can also adopt other condenser type filtering circuit except that above-mentioned capacitive filtering circuit, do not limit at this.If when adopting the filtering noise reducing circuit in the present embodiment, capacitor C 11, C12, C13, C14, C15 and C16 are the electrolyte capacitance of 1uF, also can be the electric capacity of other type, when being electrolyte capacitance, the minus earth of above-mentioned electric capacity.Resistance R 1, R2 and R3 are 50k Ω.Diode D1, D2 and D3 are used for guaranteeing that input end ADIN0, the ADIN1 of three road A/D change-over circuits of single-chip microcomputer U1 and the input voltage of ADIN2 are no more than supply voltage VCC.

As shown in Figure 3, step 1) and 2) in, comprise also among the ECU4 that a CAN bus transmission circuit connects the original vehicle-mounted CAN of a lorry (Controller Area Network) network 5, be used for receiving the vertical vehicle speed signal of lorry from vehicle-mounted CAN network 5.This CAN bus transmission circuit adopts PCA82C250 chip U2 as driver, PCA82C250 is special-purpose CAN chip for driving, be respectively CAN bus and ECU4 differential transmission and differential receiving ability are provided, and finish CANH and CANL and the conversion of CAN bus between sending, receiving.1 pin of U2 links to each other with 30 pin with 29 pin of single-chip microcomputer U1 respectively with 4 pin, and 7 pin of U2 and 6 pin meet the high-end CANH and the low side CANL of vehicle-mounted CAN network 5 respectively, is used to receive the vertical vehicle speed signal of lorry of vehicle-mounted CAN network 5 inputs.Capacitor C 21 and C22 are connected in parallel and constitute the filter regulator circuit of U2, and an end of this filter regulator circuit links to each other with 3 pin of U2, and the other end links to each other with 2 pin of U2, and 3 pin of U2 also link to each other with supply voltage VCC simultaneously, and 2 pin of U2 link to each other with ground wire.

As shown in Figure 3, step 1) and 2) in, also comprise a serial ports transceiver circuit among the ECU4, this circuit adopts Max232 chip U3 to receive and dispatch chip for driving as serial ports, it comprises that No. 2 transmitters, No. 2 receivers and a voltage generator circuit provide TIA/EIA-232-F level, meet the TIA/EIA-232-F standard.Wherein each receiver becomes 5V TTL/CMOS level with the TIA/EIA-232-F level conversion, and each transmitter becomes the TIA/EIA-232-F level with the TTL/CMOS level conversion.In the present embodiment, U3 only adopts that wherein riches all the way send device and No. one receiver.10 pin of U3 link to each other with 15 pin of single-chip microcomputer U1, and 9 pin link to each other with 16 pin of single-chip microcomputer U1, and the transmission line in the Serial Port Line of 7 pin and inclinator 31,32 links to each other, and the reception line in the Serial Port Line of 8 pin and inclinator 31,32 links to each other.Connect the positive pole that a capacitor C 31,1 pin meet C4 between 1 pin of U3 and 3 pin; Connect the positive pole that a capacitor C 32,4 pin meet C32 between 4 pin and 5 pin; Connect the positive pole that a capacitor C 33,2 pin meet C33 between 2 pin and 16 pin, and 16 pin link to each other with supply voltage VCC; 6 pin link to each other with the positive pole of a capacitor C 34, the minus earth line of C34; 15 pin ground wires link to each other with the negative pole of a capacitor C 35 simultaneously, and the positive pole of C35 links to each other with supply voltage VCC; Other pin of U3 is unsettled.In the present embodiment, U2 is the chip of a compatible RS232 standard of Texas Instruments (TI) release, and capacitor C 31, C32, C33, C34 and C35 are the polar capacitor of 1uF, but are not limited thereto.

In the step 3), note is that δ (k) and yaw velocity signal are ω through filtering noise reducing circuit and the steering wheel angle signal that undertaken after the AD sampling processing by single-chip microcomputer U1 _Rm(k), note by the side tilt angle by the boxcar of inclinator 31,32 output that serial ports receives is

With the side tilt angle of rear axle be , note is u (k) by the vertical vehicle speed signal of lorry that receives in the vehicle-mounted CAN network 5, wherein k represents k step sampling instant.

Then, single-chip microcomputer U1 calculates barycenter height of truck according to the information operation barycenter height of truck dynamic detection algorithm of gathering, and its concrete steps are as follows:

(1) theory of computation stable state lorry yaw velocity ω _Rs(k): utilize vehicle stable state steering model, according to the steering wheel angle signal δ (k) of real-time measurement, the vertical vehicle speed signal u of lorry (k) that receives in the vehicle-mounted CAN network 5, its calculating formula is as follows:

${\mathrm{\&omega;}}_{\mathrm{rs}}\left(k\right)=\frac{u\left(k\right)/\mathrm{<figure-callout\; id="1"\; label="L"\; filenames="A20081011968300111.png"\; state="\{\{state\}\}">L</figure-callout>}}{1+\mathrm{Cu}{\left(k\right)}^2}\mathrm{\&delta;}\left(k\right)$

Wherein, L is the lorry wheelbase, and C is the stable factor of vehicle.In the present embodiment, L=4.5m, C=0.0019s ²/ m ²

(2) calculation correction stable state yaw velocity

: read yaw velocity actual measured value ω _Rm(k), consider that there is certain error in the actual measurement of yaw velocity, therefore will survey yaw velocity value ω _Rm(k) and theoretical stable state yaw velocity value ω _Rs(k) be weighted on average, proofread and correct the yaw velocity value thereby obtain one, its calculating formula is as follows:

${\widehat{\mathrm{\&omega;}}}_r\left(k\right)=(1-\mathrm{\&lambda;}){\mathrm{\&omega;}}_{\mathrm{rm}}\left(k\right)+\mathrm{\&lambda;}{\mathrm{\&omega;}}_{\mathrm{rs}}\left(k\right)$

Wherein, λ is a weight coefficient, and concrete numerical value is decided according to the precision and the concrete mounting means of yaw velocity measurement mechanism 2, also can be demarcated by experiment.In the present embodiment, get λ=0.5.

(3) calculate the current side acceleration of lorry

: according to proofreading and correct yaw velocity

With current vertical speed of a motor vehicle u (k), its calculating formula is as follows:

${\hat{a}}_y\left(k\right)=u\left(k\right)\&CenterDot;{\widehat{\mathrm{\&omega;}}}_r\left(k\right)$

(4) estimate barycenter height of truck H (k): according to the lorry kinetic parameter , ε, h _a, m, and current side acceleration

And inclination angle , utilize vehicle stable state inclination model, set up the recurrence least-squares estimation algorithm of vehicle height of center of mass H (k), its calculating formula is as follows:

H(k)＝H(k-1)+Q(k)e(k)

Wherein, e (k) is a k-1 evaluated error constantly, and Q (k) is a k gain matrix constantly, and P (k) is a k matrix poised for battle constantly, and H (k) is the height of center of mass estimated value, and ε is a forgetting factor, h _aBe the height on bottom, boxcar to road surface,

Be the roll angular rigidity of lorry suspension, m is the lorry quality, and g is an acceleration of gravity.In the present embodiment, g gets 9.8m/s ², ε gets 0.99, h _aGet 0.536m, Get 6739Nm/deg.

Although disclose preferred embodiment of the present invention and accompanying drawing for the purpose of illustration, its purpose is to help to understand content of the present invention and implement according to this, but person skilled in the art, without departing from the spirit and scope of the invention and the appended claims, can do various replacements, variation and retouching.Therefore, the present invention should not be limited to most preferred embodiment and the disclosed content of accompanying drawing, and protection scope of the present invention is as the criterion with the scope that appending claims was defined.The present invention can in real time, accurately detect its height of center of mass in the lorry driving process, guarantee driver drives vehicle safety.

Claims (2)

1, a kind of dynamic detection method of barycenter height of truck, it may further comprise the steps:

1) a barycenter height of truck device for dynamically detecting is set, it comprises steering wheel angle measurement mechanism, yaw velocity measurement mechanism, dip measuring device and includes the electronic control unit of single-chip microcomputer; Program curing in the described single-chip microcomputer is provided with the height of center of mass dynamic detection algorithm module;

2) gather the steering wheel angle signal, lorry is along vertical yaw velocity signal, the side tilt angle signal of boxcar, the side tilt angle signal of lorry rear axle, vertical vehicle speed signal of lorry;

3) by described height of center of mass dynamic detection algorithm module, calculate barycenter height of truck.

2, dynamic detection method of barycenter height of truck as claimed in claim 1 is characterized in that: the calculating formula of described barycenter height of truck is as follows:

${\mathrm{\&omega;}}_{\mathrm{rs}}\left(k\right)=\frac{u\left(k\right)/L}{1+\mathrm{Cu}{\left(k\right)}^2}\mathrm{\&delta;}\left(k\right)$

${\widehat{\mathrm{\&omega;}}}_r\left(k\right)=(1-\mathrm{\&lambda;}){\mathrm{\&omega;}}_{\mathrm{rm}}\left(k\right)+\mathrm{\&lambda;}{\mathrm{\&omega;}}_{\mathrm{rs}}\left(k\right)$

${\hat{a}}_y\left(k\right)=u\left(k\right)\&CenterDot;{\widehat{\mathrm{\&omega;}}}_r\left(k\right)$

H(k)＝H(k-1)+Q(k)e(k)

In the formula, k represents k step sampling instant, ω _Rs(k) be the theoretical stable state yaw velocity of lorry signal, u (k) is the lorry vehicle speed signal, and L is the lorry wheelbase, and δ (k) is the steering wheel angle signal, and C is the stable factor of lorry,

For proofreading and correct the stable state yaw velocity, λ is a weight coefficient, ω _Rm(k) be yaw velocity,

Be the lorry side acceleration, g is an acceleration of gravity, and H (k) is a k barycenter height of truck constantly, and e (k) is a k-1 evaluated error constantly,

Be the roll angular rigidity of lorry suspension, Be the side tilt angle signal of boxcar,

Be the side tilt angle signal of lorry rear axle, H (k-1) is a k-1 barycenter height of truck constantly, h _aBe the height on bottom, boxcar to road surface, m is the lorry quality, and Q (k) is a gain matrix, and P (k-1) is a k-1 matrix poised for battle constantly, and ε is a forgetting factor, and P (k) is a k matrix poised for battle constantly.

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