CN115824482B - Six-component force testing device for realizing accurate measurement of tire force under vehicle running condition and working method - Google Patents
Six-component force testing device for realizing accurate measurement of tire force under vehicle running condition and working method Download PDFInfo
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Abstract
The invention discloses a six-component force testing device for realizing accurate measurement of tire force under vehicle running conditions and a working method thereof, wherein the six-component force testing device comprises: wheel side system and angular displacement measuring device. The wheel side system comprises a tire assembly, a signal acquisition device, a tire six-component force sensor, a connecting shaft, a brake disc and an upright post; the signal acquisition device is arranged between the wheel assembly and the tire six-component sensor; the angular displacement measuring device is installed between stand and connecting axle, and its inside mainly is provided with: the device comprises a laser source, a fixed grating, a rotating grating, a photosensitive element and a photosensitive sensor. The invention adopts the integrated connecting shaft as the connecting piece, provides the integrated information acquisition device and the angular displacement measuring device, reduces the mass of the wheel assembly, and avoids the problems of oversized unsprung mass and increased wheel track; meanwhile, the tire rotation angle is accurately measured, and the six component force of the actual tire is obtained by combining the accurately measured tire rotation angle information and the tire six component force information, so that the six component force measuring precision is improved.
Description
Technical Field
The invention relates to the technical field of vehicle testing, in particular to a six-component force testing device for accurately measuring the tire force under the driving condition of a vehicle and a working method of the device.
Background
The external load born by the vehicle comes from the interaction between the tire and the ground, and the generated tire force is the most important external force born by the vehicle under the running conditions of acceleration, braking, steering and the like; aiming at the measurement of longitudinal force, transverse force, vertical force, rolling moment, torque and yaw moment (six component force for short), the tire six component force testing device becomes essential core engineering equipment for the research and development of automobile detection and road test systems; the motion state of the vehicle at any moment can be obtained by combining the six-component force of the tire and the dynamic model of the vehicle, so that the accurate six-component force of the tire is obtained in real time, and the method has important guiding significance for the evaluation of the dynamic characteristic parameters of the tire, the dynamic measurement of the suspension characteristic of the vehicle, the experimental study of the dynamic system of the vehicle and the analysis of the steering control stability of the vehicle.
In electric vehicles, a distributed driving vehicle using an in-wheel motor as a driving mode becomes a current development hot spot due to the flexible steering control effect and strong power performance of the distributed driving vehicle; the wheel hub motor is used as a driving mode, the vehicle state feedback information such as the rotating speed, the torque and the like of each wheel can be obtained more accurately and more conveniently in real time, the controllability of the distributed driving vehicle is improved, multiple complex driving modes can be realized, but higher requirements are put forward on the steering stability control and the power performance control of the vehicle, the traditional mechanical transmission device is eliminated due to the vehicle driven in a distributed mode, and the problem of steering incompatibility is more remarkable as the lateral force of the tire is closer to the saturation limit along with the increase of the vehicle speed and the deterioration of the road surface attachment condition; therefore, in order to solve the above problems, to obtain accurate six component forces of the tire, providing a six component force testing device for accurately measuring the tire force under the driving condition of the vehicle becomes a key point for improving steering stability control.
The prior art is helpful for improving the measurement precision of the tire six-component force sensor, but has certain defects and limitations, and mainly comprises the following steps:
(1) The acting force transmission path of the existing six-component force testing device for the tire mainly comprises the following steps: ground-carcass-remade rim-rim adjustment flange-elastomer-hub adjustment flange-hub, while improving the fit with different wheels, the simultaneous use of two adapters increases the unnecessary wheel spacing between rim and hub (as in patent CN 202010806004.4), which would result in: 1) Steering envelope variation: interference can be caused when steering and suspension are compressed; 2) The kingpin offset increases: the stability of the main pin under the working conditions such as braking or uneven road surface is poor due to the increase of the offset distance of the main pin, and the service life is shortened due to the increase of the load of the hub bearing; 3) Suspension system changes: changing the track width affects the suspension geometry, reducing the vertical stiffness and roll stiffness of the suspension system.
(2) The existing tire six-component force sensor signal acquisition device and the data transmission device are divided into two parts to be installed on the tire, so that the overall quality of a wheel rim system is additionally increased, the running condition characteristics of the vehicle, such as steering, direction stability and the like, are greatly influenced, and the tire force information acquired after the tire six-component force sensor is installed is different from the actual tire force; the wheel assembly has the characteristic of small installation space, and the complex mechanical structure and the wide size of the signal acquisition device and the data transmission device increase the assembly difficulty of the signal acquisition device and the wheel assembly.
(3) Because the tire six-component force measuring device rotates along with the wheel, the measured tire force is a value under the wheel coordinate system, and the actually applied force is a force under the vehicle body coordinate system and is irrelevant to the rotation of the wheel, the force under different coordinate systems is needed to be solved, but the existing structure is mostly connected with the six-component force sensor by using a photoelectric encoder, and the following limitations exist in the connection mode: 1) In order to ensure coaxiality and parallelism, an encoder is fixed on an elastic body through a fastening bolt and an intermediate connecting device, unknown lateral prestress is introduced, and settlement errors are caused; 2) The inner ring of the encoder is connected with the tire hexad force sensor, the outer ring of the encoder is connected with the vehicle body, and when the tire hexad force sensor rotates along with the wheels, the encoder can generate output change to generate deflection deviation; 3) The encoder fixing end and the wheel knuckle are fixedly connected (as in patent CN 201810385143.7), but the method is limited by the installation space and the vehicle body structure.
Disclosure of Invention
In view of the above, the invention aims to provide a six-component force testing device for realizing accurate measurement of tire force under vehicle running conditions and a working method thereof, wherein the device can lighten the mass of a wheel assembly and avoid the problems of oversized unsprung mass and increased wheel track; meanwhile, the accurate measurement of the rotation angle of the tire is facilitated, and the measurement precision of six component forces is improved.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
the invention relates to a six-component force testing device for accurately measuring the tire force under the driving condition of a vehicle, which is characterized by comprising the following components: wheel side system and angular displacement measuring device; the wheel rim system sequentially comprises a tire assembly, a signal acquisition device, a tire hexad force sensor, a connecting shaft, a brake disc and an upright post; the signal acquisition device is fixedly arranged between the wheel assembly and the tire six-component sensor; the connecting shaft is respectively connected with the tire six-component force sensor, the brake disc and the angular displacement measuring device;
The connecting shaft comprises a first connecting disc, an intermediate shaft, a second connecting disc and a rotating shaft end; the first connecting disc is fixedly connected with the tire six-component force sensor; the second connecting disc is connected with the brake disc through bolts;
The rotating shaft end penetrates through the upright post and is fixedly connected with a mounting sleeve in the angular displacement measuring device so as to realize synchronous rotation of the mounting sleeve and the connecting shaft, and the angular displacement measuring device is provided with a laser source, a fixed grating, a rotating grating, a photosensitive element, a photosensitive sensor and a PCB; wherein the laser source, the fixed grating, the photosensitive sensor and the PCB board are connected to a shell of the relative fixed angular displacement measuring device, the rotary grating and the photosensitive element are connected to a relative rotary mounting sleeve,
When the wheel rotates, the rotary grating, the photosensitive element and the mounting sleeve in the angular displacement measuring device rotate along with the wheel.
Further, the angular displacement measuring device is of an integrated structure and is arranged between the upright post and the connecting shaft; the two sides of the outer end surface of the front shell of the device are respectively provided with a plurality of bolt connecting holes, the surface of the upright post is provided with a plurality of corresponding connecting holes, and the plurality of bolt connecting holes are in one-to-one correspondence with the plurality of corresponding connecting holes and are fastened through bolts; the installation sleeve is provided with a plurality of initial angle locating holes, the connecting shaft is provided with a plurality of corresponding locating connecting holes, and the initial angle locating holes are connected with the locating connecting holes in a one-to-one correspondence mode.
Further, a first positioning shaft shoulder and a second positioning shaft shoulder are arranged at the center of the mounting sleeve, and the first shaft shoulder is used for positioning the bearing; the center of the circumference of the second positioning shaft shoulder is provided with a plurality of shaft shoulder positioning holes, the inner circumference of the rotating grating is provided with a plurality of shaft shoulder connecting holes, and the shaft shoulder positioning holes are correspondingly connected with the shaft shoulder connecting holes one by one; the outer circumference of the rotary grating is divided into a first photometry area, a second photometry area, a third photometry area and a fourth photometry area, and the four photometry areas are respectively provided with a first photosensitive element, a second photosensitive element, a third photosensitive element and a fourth photosensitive element.
Further, a light source mounting seat is arranged in the front shell of the angular displacement measuring device, and the laser source is mounted on the light source mounting seat; the lens and the fixed grating are arranged right in front of the laser source and correspond to the rotating grating; the front end of the PCB is provided with a plurality of photosensitive sensors for receiving light intensity signals transmitted by the laser source through the lens, the fixed grating and the rotary grating; the inner circumference of the PCB is provided with a plurality of fixing holes which are connected with a positioning pin shaft arranged in the rear shell of the device.
Further, the connecting shaft is an integrally formed part and comprises a first connecting disc, an intermediate shaft, a second connecting disc and a rotating shaft end which are sequentially formed; the upright post is connected with the rotating shaft end in an interference fit manner through a bearing; the second connecting disc is connected with the brake disc through bolts; the first connecting disc is connected with the tire six-component sensor.
Further, the tire hexad force sensor is arranged in an inner ring and an outer ring, and the inner ring is connected with the first connecting disc; the outer ring is connected with the signal acquisition device.
Further, the signal acquisition device is an integrated structure, including: the device comprises a shell, a cover plate and a signal acquisition card; the casing is integrated into one piece finished piece, includes: the tire assembly comprises a boss, a flange plate and a positioning block, wherein a plurality of first connecting holes are formed in the inner circumference of the outer side of the boss at equal intervals, a plurality of mounting holes are formed in the center of the circumference of a rim of the tire assembly, and the plurality of first connecting holes are correspondingly arranged with the plurality of mounting holes and are connected through bolts; the flange plate is provided with a plurality of second connecting holes which are arranged at equal intervals, and the outer ring corresponds to the second connecting holes and is connected with the second connecting holes through bolts.
Further, a plurality of fifth connecting holes are formed in the positioning block, a plurality of equidistant third connecting holes are formed in the inner circumference of the inner side of the boss, a plurality of first fixing holes are formed in the inner circumference of the cover plate, a plurality of second fixing holes are formed in the outer circumference of the cover plate, the first fixing holes are in one-to-one correspondence with the third connecting holes and are connected through bolts, the second fixing holes are in one-to-one correspondence with the fifth connecting holes, and the positioning block is also used for positioning the signal acquisition card.
Further, the signal acquisition card is provided with a plurality of positioning installation grooves and a plurality of fixing butt joint holes on the outer circumference, the positioning installation grooves correspond to the positioning blocks, the outer circumference of the inner side of the boss is provided with a plurality of fourth connecting holes, and the fixing butt joint holes are correspondingly connected with the fourth connecting holes one by one; and the signal acquisition card is also provided with a wireless transmission module, a signal amplification module, a signal acquisition module, an acquisition signal processing module and a battery module.
Based on the structure, the invention adopts the working method of the tire six-component force testing device suitable for the distributed driving vehicle, and the working method is carried out according to the following steps:
Step S1: the upper computer sets the six-component tyre testing device in a working mode, sends a control instruction to the wireless transmission module, and monitors a return signal in real time;
Step S2: the signal amplifying module, the signal acquisition module, the acquisition signal processing module and the battery module in the signal acquisition device receive the instruction of the upper computer to start working;
Step S3: in operation of the wheel, the transmission path of the tire force is as follows: the wheel assembly is connected to the signal acquisition device, a flange on the signal acquisition device is connected to the outer ring of the tire hexad force sensor, the inner ring of the tire hexad force sensor is connected to the connecting shaft, and then is transmitted to the vehicle body, and in a fixed mode, an elastic strain beam between the inner ring and the outer ring of the tire hexad force sensor is deformed when the tire runs;
step S4: the six-way Wheatstone bridge formed by the strain gauges adhered to the strain beams generates voltage signals, and the voltage signals are amplified, filtered and inter-dimensional decoupling processed through the signal amplifying module, the signal acquisition module and the acquisition signal processing module to obtain accurate six-component force signals of the tire;
Step S5: when the wheel rotates, the angular displacement measuring device connected between the upright post and the connecting shaft rotates along with the wheel, wherein four light areas of the rotating grating are respectively defined as 0 to 90 degrees, 90 degrees to 180 degrees, 180 degrees to 270 degrees, 270 degrees to 360 degrees and correspond to four photosensitive elements respectively, light rays of the laser source are converted into light rays in a single direction after passing through the fixed grating and projected onto the rotating grating and the photosensitive elements, and the rotation angle of the tire can be measured at the moment by combining the light intensity obtained by the single light rays passing through the rotating grating received by the photosensitive sensor;
step S6: and (3) transmitting the processed tire six-component force signal to an upper computer for acquisition and analysis through a wireless transmission module and a tire corner signal measured by an angular displacement measuring device, and returning to the step (s 1) to wait for the next acquisition task.
Compared with the prior art, the invention has the following beneficial effects:
(1) The integrated connecting shaft is adopted as a connecting piece and is directly connected with the tire six-component force sensor, so that the use of a connecting adapter is effectively reduced, the problem of increased wheel track caused by the connection of multiple adapters of the existing sensor testing device is solved, and the original running performance and suspension performance of the vehicle are ensured; meanwhile, the signal acquisition device is arranged in the wheel side system, and the data transmission device is arranged outside the wheel side system, so that the additional mass of the wheel side system is reduced, and the influence on the steering and control stability of the vehicle after the tire six-component force testing device and the tire assembly are assembled is solved; meanwhile, as the data transmission device is not required to be connected with the signal acquisition device, the assembly complexity is reduced, the structure of the tire six-component force testing device is simplified, and the tire six-component force testing precision is improved.
(2) The angular displacement measuring device is arranged between the connecting shaft and the upright post, and is not required to be arranged on the tire six-component force sensor, so that the influence of unknown lateral pretightening force on the tire six-component force caused by bolting is eliminated, and the tire six-component force rotation decoupling precision is improved; meanwhile, an initial angle positioning hole is formed in the mounting sleeve of the angular displacement measuring device, and the coordinate system of the wheel and the coordinate system of the six-component force sensor of the tire can be accurately determined to be in a superposition state only by being connected with the positioning connecting hole formed in the connecting shaft, so that accumulated errors caused by inaccurate initial angle measurement are eliminated.
(3) In order to improve the continuity of the output angle signal of the angular displacement measuring device, a mode of combining a fixed grating with a rotating grating is adopted, the light intensity after passing through the two gratings is measured through a photosensitive sensor, the rotation angle of the gratings at the moment, namely the rotation angle of the tire, is calculated by using a Malus law, and the signal can be directly and continuously output in the form of analog quantity, so that the accuracy of angular displacement measurement is improved; the device has the advantages of simple structure, small volume, low manufacturing cost and the like.
Drawings
The invention is described in further detail below with reference to the attached drawings and detailed description:
FIG. 1 is a schematic view of the overall structure of a six-component tire testing device according to an embodiment of the present invention;
FIG. 2 is an exploded view of the overall structure of a six-component tire testing device according to an embodiment of the present invention;
FIG. 3 is an exploded view of an angular displacement measuring device according to an embodiment of the present invention;
FIG. 4 is a schematic view of a subdivision structure of an angular displacement measuring device in an embodiment of the present invention;
FIG. 5 is an exploded view of a signal acquisition device in an embodiment of the invention;
FIG. 6 is a schematic view of a connection shaft subdivision structure in an embodiment of the present invention;
Fig. 7, 8 are partial views of fig. 6;
In the figure: 1-a wheel rim system; 2-an angular displacement measuring device; 10-a tire assembly; 11-a signal acquisition device; 12-tire hexacomponent sensor; 13-connecting shaft; 14-a brake disc; 15-stand columns; 20-an angular displacement measuring device front housing; 21-a laser source; 22-fixing the grating; 23-bearings; 24-mounting a sleeve; 25-rotating the grating; 26-a photosensitive element; 27-a photosensitive sensor; 28-a PCB board; 29-an angular displacement measuring device rear housing; 10a mounting holes; 11 a-a housing; 11 b-cover plate; 11 c-a signal acquisition card; 11a 1-boss; 11a 2-flange plate; 11a 3-positioning blocks; 11a 11-first connection holes; 11a 12-a third connecting hole; 11a 13-fourth connection holes; 11a 21-a second connection hole; 11b 1-a first fixing hole; 11b 2-a second fixing hole; 11a 31-fifth connecting holes; 12 a-an inner ring; 12 b-an outer ring; 13 a-positioning connection holes; 13 b-a first connection disc; 13 c-an intermediate shaft; 13 d-a second land; 13 e-rotating shaft ends; 15 a-corresponding connection holes; 20 a-a bolt connection hole; 24 a-initial angular positioning hole; 24 b-a first shoulder; 24 c-a second positioning shoulder; 24 d-shaft shoulder positioning holes; 25 a-a shoulder connection hole; 25b 1-a first photometric area; 25b 2-a second photometric area; 25b 3-a third photometric area; 25b 4-fourth photometric area; 25c 1-a first photosensitive element; 25c 2-a second photosensitive element; 25c 3-a third photosensor; 25c 4-fourth photosensitive elements; 28 a-a fixing hole; 29 a-positioning pin.
Detailed Description
The invention will be further described with reference to the accompanying drawings and examples.
It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
As shown in fig. 1,2 and 3, the present embodiment provides a six-component force testing device for accurately measuring the tire force under the driving condition of a vehicle, which comprises: wheel side system 1 and angular displacement measuring device 2.
The wheel rim system comprises a tire assembly 10, a signal acquisition device 11, a tire hexad force sensor 12, a connecting shaft 13, a brake disc 14 and a stand column 15; the signal acquisition device 11 is arranged between the tire assembly 10 and the tire six-component sensor 12; the connecting shaft is respectively connected with the tire six-component sensor 12, the brake disc 14 and the angular displacement measuring device 2; wherein the angular displacement measuring device comprises: the angular displacement measuring device comprises a front shell 20, a laser source 21, a fixed grating 22, a bearing 23, a mounting sleeve 24, a rotating grating 25, a photosensitive element 26, a photosensitive sensor 27, a PCB 28, a rear shell 29 of the angular displacement measuring device and a lens and a bearing gasket.
As shown in fig. 4, the angular displacement measuring device 2 is designed as an integrated structure, which improves the anti-interference capability, and is installed between the upright post 15 and the connecting shaft 13; two connecting devices are respectively arranged on two sides of the outer end face of the front shell 20 of the angular displacement measuring device, two bolt connecting holes 20a are respectively arranged above the two connecting devices, two corresponding connecting holes 15a are respectively arranged on two sides of the surface of the upright post 15, the bolt connecting holes 20a are in one-to-one correspondence with the corresponding connecting holes 15a and are fastened through bolts, the fixed end of the angular displacement measuring device 2 is tightly connected with the upright post 15, the angular displacement measuring device is guaranteed to rotate along with a wheel side system, and meanwhile, the lateral pretightening force of a tire hexad force sensor by a traditional connecting mode is eliminated; three initial angle positioning holes 24a are formed in the circumferential direction of the mounting sleeve 24, three corresponding positioning connecting holes 13a are formed in the connecting shaft 13, the mounting sleeve 24 is sleeved on the connecting shaft 13, the initial angle positioning holes 24a are in one-to-one correspondence with the positioning connecting holes 13a and are fastened through bolts, the angular displacement measuring device 2 rotates along with the connecting shaft 13, and the initial test angle is zero while the coordinate system of the six component force 12 of the tire coincides with the coordinate system of the vehicle body can be guaranteed through the connection.
In this embodiment, a first positioning shaft shoulder 24b and a second positioning shaft shoulder 24c are disposed at the center of the mounting sleeve 24, the first shaft shoulder 24b is used for positioning the bearing 23, and the front housing 20 of the angular displacement measuring device and the bearing 23 are connected in an interference fit manner; the bearing 23 and the first positioning shaft shoulder 24b of the mounting sleeve 24 are connected in an interference fit manner, so that the housing of the angular displacement measuring device is kept stationary while the mounting sleeve 24 rotates along with the connecting shaft 13; four shaft shoulder positioning holes 24d are formed in the circumference of the second positioning shaft shoulder 24c, four shaft shoulder connecting holes 25a are formed in the circumference of the inner circle of the rotary grating 25, and the shaft shoulder positioning holes 24d are connected with the shaft shoulder connecting holes 25a in a one-to-one correspondence manner; the outer circumference of the rotating grating 25 is divided into a first photometry area 25b1, a second photometry area 25b2, a third photometry area 25b3 and a fourth photometry area 25b4, and the four photometry areas are respectively provided with a first photosensitive element 25c1, a second photosensitive element 25c2, a third photosensitive element 25c3 and a fourth photosensitive element 25c4.
In this embodiment, the laser source 21 is mounted on a light source mounting seat disposed inside the front case 20 of the angular displacement measuring device; the front end of the PCB 28 is provided with two photosensitive sensors 27, and the photosensitive sensors 27 receive light intensity signals transmitted by the laser source 21 through the lens, the fixed grating 22 and the rotary grating 25; four fixing holes 28a are formed in the inner circumference of the PCB 28, and the four fixing holes 28a are connected with a positioning pin shaft 29a arranged in the rear shell 29 of the angular displacement measuring device, so that the PCB 28 and the rear shell 29 of the angular displacement measuring device are relatively static.
Four three light measuring areas are uniformly arranged on the rotary grating 25 in the circumferential direction, namely a first light measuring area, a second light measuring area, a third light measuring area and a fourth light measuring area in sequence, wherein the first light measuring area and the third light measuring area are horizontal gratings, and the second light measuring area and the fourth light measuring area are vertical gratings.
Tire hexacomponent sensor, model Type 9266A1, is available from KISTLER company, switzerland; the photosensitive element uses a light-sensitive resistor GL5501 of Crystal wound and vertical technology company; the photosensor uses a digital photosensor HLALS AC-K1 from the company of crystal creation and biotechnology.
In this embodiment, the working principle of the angular displacement measuring device is as follows: under the running condition of the vehicle, the rotating grating 25 in the angular displacement measuring device 2 rotates together with the connecting shaft 13, the first light measuring area and the third light measuring area which are arranged on the rotating grating 25 are horizontal gratings, the second light measuring area and the fourth light measuring area are vertical gratings, the corresponding measuring angles of the first light measuring area and the fourth light measuring area are 0 DEG to 360 DEG, and the photosensitive elements arranged on the photosensitive elements are used for measuring the light intensity signals of the laser source 21 passing through the horizontally arranged fixed grating 22; for example, when the first photosensor 25c1 detects the light intensity signal, at the moment, the rotation angle of the tire is in the range of 0 ° to 90 °, the laser source 21 passes through the horizontal grating 22 and the first light measuring region 25b1 horizontally arranged, and at the moment, the light transmission amount is maximum, according to the law of malus, the rotation angle is 0 °, and when the tire assembly 10 rotates to 90 °, the light transmission amount is 0, and thus the rotation of the tire by 90 ° can be measured; when the tire continues to rotate, the second photosensitive element 25c2 obtains a light intensity signal, the second photometry area 25b2 rotates from a vertical state to a horizontal state, and the above measurement steps are repeated; the buffer accumulates the rotation angle recorded in the last step with the angle at the moment until the tire rotates 360 degrees, the buffer is cleared, and the angular displacement measuring device performs angle measurement again from the first photometry area.
As shown in fig. 5 and 6, the connecting shaft 13 is an integrally molded part, and includes a first connecting disc 13b, a middle shaft 13c, a second connecting disc 13d and a rotating shaft end 13e which are sequentially molded; the upright 15 is connected with the rotating shaft end 13e in an interference fit manner through a bearing; the second connecting disc 13d is connected with the brake disc 14 through bolts; the first connection plate 13b is connected to the tire six-component sensor 12.
In this embodiment, the six-component sensor 12 is disposed in an inner ring and an outer ring, and the inner ring 12a is connected to the first connecting disc 13 b; the outer ring 12b is connected with the signal acquisition device 11; the signal acquisition device 11 is an integrated structure, and the signal acquisition device 11 includes: a housing 11a, a cover plate 11b, and a signal acquisition card 11c; the casing is integrated into one piece finished piece, includes: the tire assembly comprises a boss 11a1, a flange plate 11a2 and a positioning block 11a3, wherein four first connecting holes 11a11 are formed in the inner circumference of the outer side of the boss 11a 1at equal intervals, four mounting holes 10a are formed in the center of the circumference of a rim of the tire assembly 10, and a plurality of first connecting holes 11a11 are correspondingly arranged with a plurality of mounting holes 10a and are connected through bolts; the flange 11a2 is provided with a plurality of second connecting holes 11a21 arranged at equal intervals, and the outer ring 12b corresponds to the second connecting holes 11a21 and is connected by bolts.
In this embodiment, the positioning block 11a3 is provided with a plurality of fifth connection holes 11a31, four equidistant third connection holes 11a12 are provided on the inner circumference of the inner side of the boss 11a1, four first fixing holes 11b1 are provided on the inner circumference of the cover plate 11b, four second fixing holes 11b2 are provided on the outer circumference of the cover plate 11b, the four first fixing holes 11b1 are in one-to-one correspondence with the four third connection holes 11a12 and are connected through bolts, the four second fixing holes 11b2 are in one-to-one correspondence with the four fifth connection holes 11a31, and the positioning block 11a3 is also used for positioning the signal acquisition card 11c.
In this embodiment, the signal acquisition card 11c is provided with four positioning and mounting grooves 11c 1and four fixing and docking holes 11c2 on the outer circumference, the four positioning and mounting grooves 11c 1and the four positioning blocks 11a3 are correspondingly inserted and matched for positioning, the outer circumference of the inner side of the boss 11a1 is provided with four fourth connecting holes 11a13, and the four fixing and docking holes 11c2 are correspondingly connected with the four fourth connecting holes 11a13 one by one; the signal acquisition card 11c is also provided with a wireless transmission module, a signal amplification module, a signal acquisition processing module and a battery module, wherein the signal amplification module adopts a single-power AD623 instrument program-controlled amplifier to amplify six component forces of the tire respectively, the amplification factor is 1.5-1000 times and is adjustable, the module adopts a 12V direct-current power supply to supply power, the battery module supplies power, the AD623 instrument amplifier can carry out filtering treatment on the signal, the interference of noise signals on weak voltage signals is effectively reduced, and the effective signals after filtering amplification are sent to the signal acquisition module, so that the normal operation of signal acquisition is ensured; the signal acquisition module adopts a 16-bit and 8-channel synchronous sampling AD7606 analog-to-digital converter, the sampling rate of each channel can reach 200KHz, the signal acquisition module has a 40dB anti-aliasing suppression characteristic, a digital filter is arranged in the signal acquisition module, the voltage acquisition signal is further processed, the real information is restored, the module adopts a 5V direct current power supply to supply power, the acquisition of the output voltage of each bridge of the tire six-component force sensor is realized, and the acquired analog quantity signal is converted into a digital signal; the signal wireless transmission module uses an ATK-ESP8266 serial port module, the module is small in size and easy to install, digital signals acquired by the signal acquisition module are transmitted to the wireless signal receiving device and transmitted to the upper computer, and the wireless transmission module is also used for receiving signal instructions of the upper computer and controlling the lower computer; the battery module includes: the power supply module adopts a 12V lithium battery to supply power, and the residual power monitoring module adopts a MAX2788 chip for monitoring the residual power of the whole battery pack, and can generate an alarm signal when the power is insufficient.
By combining the above embodiments, the present embodiment further provides a method for using a six-component force testing device for realizing accurate measurement of tire force under vehicle driving conditions, which specifically includes the following steps:
Step S1: the upper computer sets the six-component tyre testing device in a working mode, sends a control instruction to the wireless transmission module, and monitors a return signal in real time;
Step S2: the signal amplifying module, the signal acquisition module, the acquisition signal processing module and the battery module in the signal acquisition device receive the instruction of the upper computer to start working;
Step S3: in operation of the wheel, the transmission path of the tire force is as follows: the tire assembly 10 is randomly transmitted to a vehicle body through a signal acquisition device 11, a flange on the signal acquisition device 11, a tire six-component force sensor outer ring 12b, a tire six-component force sensor inner ring 12a and a connecting shaft 13, wherein the tire six-component force sensor inner ring is connected with the connecting shaft, and in a fixed mode, an elastic strain beam between the tire six-component force sensor inner ring and the tire outer ring deforms when the tire runs;
step S4: the six-way Wheatstone bridge formed by the strain gauges adhered to the strain beams generates voltage signals, and the voltage signals are amplified, filtered and inter-dimensional decoupling processed through the signal amplifying module, the signal acquisition module and the acquisition signal processing module to obtain accurate six-component force signals of the tire;
Step S5: when the wheel rotates, the angular displacement measuring device connected between the upright post and the connecting shaft rotates along with the wheel, wherein four light areas of the rotating grid are respectively defined as 0 to 90 degrees, 90 to 180 degrees, 180 to 270 degrees, 270 to 360 degrees and respectively correspond to four photosensitive elements; the light of the laser source is converted into light in a single direction after passing through the fixed grating and then projected onto the rotating grating and the photosensitive element, and the rotation angle of the tire can be measured by combining the light intensity obtained by the single light passing through the rotating grating received by the photosensitive sensor;
step S6: and (3) transmitting the processed tire six-component force signal to an upper computer for acquisition and analysis through a wireless transmission module and a tire corner signal measured by an angular displacement measuring device, and returning to the step (s 1) to wait for the next acquisition task.
The foregoing description is only of the preferred embodiments of the invention, and all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Claims (7)
1. The utility model provides a realize six component testing arrangement of accurate measurement of vehicle running operating mode tire force which characterized in that, testing arrangement includes: a wheel side system (1) and an angular displacement measuring device (2); the wheel rim system sequentially comprises a tire assembly (10), a signal acquisition device (11), a tire six-component sensor (12), a connecting shaft (13), a brake disc (14) and an upright post (15); the signal acquisition device (11) is fixedly arranged between the tire assembly (10) and the tire six-component sensor (12); the connecting shaft (13) is respectively connected with the tire six-component sensor (12), the brake disc (14) and the angular displacement measuring device (2);
The connecting shaft (13) comprises a first connecting disc (13 b), an intermediate shaft (13 c), a second connecting disc (13 d) and a rotating shaft end (13 e); the first connecting disc (13 b) is fixedly connected with the tire six-component sensor (12); the second connecting disc (13 d) is connected with the brake disc (14) through bolts;
The rotating shaft end (13 e) penetrates through the upright post (15) and is fixedly connected with a mounting sleeve (24) in the angular displacement measuring device (2) so as to realize synchronous rotation of the mounting sleeve (24) and the connecting shaft (13), and the angular displacement measuring device (2) is provided with a laser source (21), a fixed grating (22), a rotating grating (25), a photosensitive element (26), a photosensitive sensor (27) and a PCB (printed circuit board) (28); the laser source (21), the fixed grating (22), the photosensitive sensor (27) and the PCB (28) are connected to a shell of the relatively fixed angular displacement measuring device (2), and the rotary grating (25) and the photosensitive element (26) are connected to a relatively rotary mounting sleeve (24);
When the wheel rotates, a rotating grating (25), a photosensitive element (26) and a mounting sleeve (24) in the angular displacement measuring device rotate along with the wheel; a plurality of bolt connecting holes (20 a) are respectively formed in two sides of the outer end face of the front shell of the angular displacement measuring device, a plurality of corresponding connecting holes (15 a) are formed in the surface of the upright post, and the plurality of bolt connecting holes are in one-to-one correspondence with the plurality of corresponding connecting holes and are fastened through bolts; the mounting sleeve is provided with a plurality of initial angle positioning holes (24 a), the connecting shaft is provided with a plurality of corresponding positioning connecting holes (13 a), the mounting sleeve (24) is sleeved on the connecting shaft (13), and the plurality of initial angle positioning holes are correspondingly connected with the plurality of corresponding positioning connecting holes one by one; a light source mounting seat is arranged in the front shell of the angular displacement measuring device, and the laser source (21) is mounted on the light source mounting seat; the lens and the fixed grating (22) are arranged right in front of the laser source and correspond to the rotating grating (25); the front end of the PCB is provided with a plurality of photosensitive sensors (27), and the photosensitive sensors receive light intensity signals transmitted by the laser source through the lens, the fixed grating and the rotating grating; the inner circumference of the PCB (28) is provided with a plurality of fixing holes (28 a), and the fixing holes are connected with a positioning pin shaft (29 a) arranged in the rear shell of the testing device, so that the PCB and the rear shell are relatively static; the outer circumference of the rotary grating is divided into a first photometry area (25 b 1), a second photometry area (25 b 2), a third photometry area (25 b 3) and a fourth photometry area (25 b 4), and a first photosensitive element (25 c 1), a second photosensitive element (25 c 2), a third photosensitive element (25 c 3) and a fourth photosensitive element (25 c 4) are respectively arranged in the four photometry areas, wherein the first photometry area and the third photometry area are horizontal gratings, and the second photometry area and the fourth photometry area are vertical gratings.
2. The six-component force testing device for realizing accurate measurement of tire force under vehicle running conditions according to claim 1, wherein a first positioning shaft shoulder (24 b) and a second positioning shaft shoulder (24 c) are arranged in the center of the mounting sleeve, and the first positioning shaft shoulder is used for positioning a bearing (23); the second positioning shaft shoulder circumference center is provided with a plurality of shaft shoulder positioning holes (24 d), the inner circumference of the rotating grating is provided with a plurality of shaft shoulder connecting holes (25 a), and the shaft shoulder positioning holes are connected with the shaft shoulder connecting holes in a one-to-one correspondence manner.
3. The six-component force testing device for realizing accurate measurement of tire force under vehicle driving conditions according to claim 1, wherein the tire six-component force sensor is in an inner ring and outer ring arrangement mode, and the inner ring (12 a) is connected with the first connecting disc (13 b); the outer ring (12 b) is connected with the signal acquisition device (11).
4. A six-component force testing device for realizing accurate measurement of tire force under vehicle driving conditions according to claim 3, wherein the signal acquisition device (11) is of an integrated structure, and comprises: a housing (11 a), a cover plate (11 b), and a signal acquisition card (11 c); the casing is integrated into one piece finished piece, includes: the tire assembly comprises a boss (11 a 1), a flange plate (11 a 2) and a positioning block (11 a 3), wherein a plurality of first connecting holes (11 a 11) are formed in the inner circumference of the outer side of the boss at equal intervals, a plurality of mounting holes are formed in the center of the circumference of a rim of the tire assembly, and the plurality of first connecting holes are correspondingly arranged with the plurality of mounting holes and are connected through bolts; the flange plate is provided with a plurality of second connecting holes (11 a 21) which are arranged at equal intervals, and the outer ring corresponds to the second connecting holes and is connected with the second connecting holes through bolts.
5. The six-component testing device for accurately measuring the tire force under the driving condition of the vehicle according to claim 4, wherein a plurality of fifth connecting holes (11 a 31) are formed in the positioning block (11 a 3), a plurality of equidistant third connecting holes (11 a 12) are formed in the inner circumference of the boss, a plurality of first fixing holes (11 b 1) are formed in the inner circumference of the cover plate, a plurality of second fixing holes (11 b 2) are formed in the outer circumference of the cover plate, the first fixing holes are in one-to-one correspondence with the third connecting holes and are connected through bolts, the second fixing holes are in one-to-one correspondence with the fifth connecting holes, and the positioning block is also used for positioning the signal acquisition card.
6. The six-component force testing device for accurately measuring the tire force under the driving condition of the vehicle according to claim 5, wherein the signal acquisition card is provided with a plurality of positioning mounting grooves (11 c 1) and a plurality of fixing butt joint holes (11 c 2) on the outer circumference, a plurality of positioning mounting grooves correspond to a plurality of positioning blocks, a plurality of fourth connecting holes (11 a 13) are formed on the outer circumference of the inner side of the boss, and a plurality of fixing butt joint holes are correspondingly connected with a plurality of fourth connecting holes one by one; and the signal acquisition card is also provided with a wireless transmission module, a signal amplification module, a signal acquisition module, an acquisition signal processing module and a battery module.
7. The working method of the six-component force testing device for realizing accurate measurement of the tire force under the running condition of the vehicle is characterized by comprising the following steps of: comprising the use of a six-component testing device according to any one of claims 1-6, and according to the following steps:
step S1: the upper computer sets the six-component force testing device in a working mode, sends a control instruction to the wireless transmission module, and monitors a return signal in real time;
Step S2: the signal amplifying module, the signal acquisition module, the acquisition signal processing module and the battery module in the signal acquisition device receive the instruction of the upper computer to start working;
Step S3: in operation of the wheel, the transmission path of the tire force is as follows: the wheel assembly is connected to the signal acquisition device, a flange on the signal acquisition device is connected to the outer ring of the tire hexad force sensor, the inner ring of the tire hexad force sensor is connected to the connecting shaft, and then is transmitted to the vehicle body, and in a fixed mode, an elastic strain beam between the inner ring and the outer ring of the tire hexad force sensor is deformed when the tire runs;
step S4: the six-way Wheatstone bridge formed by the strain gauges adhered to the strain beams generates voltage signals, and the voltage signals are amplified, filtered and inter-dimensional decoupling processed through the signal amplifying module, the signal acquisition module and the acquisition signal processing module to obtain accurate six-component force signals of the tire;
Step S5: when the wheel rotates, the angular displacement measuring device connected between the upright post and the connecting shaft rotates along with the wheel, wherein four light areas of the rotating grid are respectively defined as 0 to 90 degrees, 90 to 180 degrees, 180 to 270 degrees, 270 to 360 degrees and respectively correspond to four photosensitive elements; the light of the laser source is converted into light in a single direction after passing through the fixed grating and then projected onto the rotating grating and the photosensitive element, and the rotation angle of the tire can be obtained by combining the light intensity obtained by the single light passing through the rotating grating received by the photosensitive sensor and applying the Malus law;
step S6: and (3) transmitting the processed tire six-component force signal to an upper computer for acquisition and analysis through a wireless transmission module and a tire corner signal measured by an angular displacement measuring device, and returning to the step (s 1) to wait for the next acquisition task.
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