CN113267353B

CN113267353B - Road test method for verifying development of durability of automobile

Info

Publication number: CN113267353B
Application number: CN202110762375.1A
Authority: CN
Inventors: 于尚恒; 蒋兵; 王诗虎; 袁超
Original assignee: Chery Commercial Vehicle Anhui Co Ltd
Current assignee: Chery Automobile Co Ltd
Priority date: 2021-07-06
Filing date: 2021-07-06
Publication date: 2024-03-08
Anticipated expiration: 2041-07-06
Also published as: CN113267353A

Abstract

A road test method for verifying automobile durability development belongs to the technical field of automobile durability tests, and comprises the steps of constructing a driving test road; the test vehicle circularly runs through complex road conditions for many times and then enters a high-speed loop to carry out variable speed circulation running, so that durable subcycling of the whole vehicle structure is completed; operating the durable subcycles corresponding times according to different driving modes; comprehensively checking whether the preset part of the test vehicle is abnormal, if not, continuing to perform durable subcycle after tire transposition until the preset part of the test vehicle is abnormal and recording; the test method has the beneficial effects that the automobile can circularly run under a plurality of set road conditions, the durability and reliability of different power output under a plurality of driving modes can be verified, the durability of all parts of the whole automobile under a plurality of road conditions and at a plurality of running speeds are reduced, the test cost is reduced, the reliability of test results is ensured, and the safety and reliability of products are effectively ensured.

Description

Road test method for verifying development of durability of automobile

Technical Field

The invention relates to the technical field of automobile durability tests, in particular to a road test method for verifying automobile durability development.

Background

Along with the development of the automobile industry, in order to adapt to the use requirements of different users of all people, automobile developers correspondingly push out automobiles with different driving modes, and the automobile driving modes are as follows: ECO (economy mode), SPORT (SPORT mode), NORMAL (OFF-ROAD mode), SNOW (snowfield mode), etc., the power output in each mode is different, and the durability requirements for each part of the automobile are different, and each supplier adopts an average value to develop a development scheme with minimum cost in design and development, but the performance in real vehicle use is not necessarily satisfactory.

Therefore, in order to ensure that no durability fault occurs under any driving mode, the customer can provide driving riding feeling well, so that the product is safer and more reliable, and the durability verification is carried out on automobiles in various driving modes, thereby having certain necessity and practical value.

Disclosure of Invention

In order to solve the technical problems, the invention provides a road test method for verifying the development of the durability of an automobile, which can verify the durability and the reliability of different power output when the automobile is in various driving modes, and can effectively ensure the safety and the reliability of products.

In order to achieve the above purpose, the technical scheme adopted by the invention for solving the technical problems is as follows: the road test method for verifying the development of the durability of the automobile comprises the following steps:

step 1: constructing a driving test road, wherein the driving test road comprises a reinforced durable road, a standard ramp area and a high-speed loop;

step 2: the test vehicle carries out multiple complex road condition circulating running through the reinforced durable road and the standard ramp area, then enters a high-speed loop to carry out variable speed circulating running, and the durable subcycling of the whole vehicle structure is completed;

step 3: operating the durable subcycles corresponding times according to different driving modes;

step 4: after finishing the durable sub-circulation for the set times, comprehensively checking whether the preset part of the test vehicle is abnormal, if not, continuing to perform durable sub-circulation according to the methods of the step 2 and the step 3 after the tire is transposed until the preset part of the test vehicle is abnormal, wherein the reliability and the durability of the preset part are not in accordance with the requirements, and recording the abnormal situation.

The inner side of the high-speed loop is connected with the reinforced durable road and the entrance of the standard ramp area through a plurality of branches.

The reinforced durable road comprises a residential area and a city square, and the residential area and the city square are connected through a plurality of characteristic roads.

The characteristic ways comprise a No. 1 characteristic way, a No. 2 characteristic way, a No. 3 characteristic way, a No. 4 characteristic way, a No. 5 characteristic way, a No. 6 characteristic way, a No. 7 characteristic way and a No. 8 characteristic way which are sequentially arranged, the No. 1 characteristic way and the No. 7 characteristic way form a No. 1 circulation way, the No. 3 characteristic way and the No. 7 characteristic way form a No. 2 circulation way, and the No. 4 characteristic way and the No. 6 characteristic way form a No. 3 circulation way.

The process that the test vehicle passes through the reinforced durable road sequentially passes through the No. 1 circulating path, the No. 2 characteristic path, the No. 8 characteristic path, the No. 2 circulating path, the No. 3 circulating path, the No. 4 characteristic path, the No. 5 characteristic path, the residential area, the No. 6 characteristic path and the city square, and the city square drives into the standard ramp area.

And the two ends of the No. 4 characteristic path, the No. 5 characteristic path and the No. 6 characteristic path are respectively connected through a steering test path.

The No. 1 characteristic road comprises an S-shaped stone road, a concrete patch road and a mixed arch road which are sequentially arranged along the running direction of the test vehicle; the No. 7 characteristic road comprises a rope road, a well cover road, a sine barrier and a pebble road which are sequentially arranged along the running direction of the test vehicle.

The running route of the No. 1 circulating path is as follows: the test vehicle passes through the S-shaped stone road, the concrete patch road and the mixed arch road in sequence at the speed of 40-45 km/h, passes through the rope road at the speed of 15-20 km/h and keeps the II-gear or the D-gear, passes through the manhole cover road, the sine barrier and the snake-shaped pebble road in sequence at the speed of 20-25 km/h and keeps the III-gear or the D-gear.

The No. 2 characteristic road comprises a railway road mouth, a vibrating road III, a prototype pothole road, a short wave road, a left wheel curb impact road and a 30-degree angle obstacle road which are sequentially arranged along the running direction of a test vehicle, the test vehicle sequentially passes through the railway road mouth and the vibrating road III at a speed of 35-40 km/h, is lightly braked and decelerated to 15-20 km/h, passes through the prototype pothole road at a speed of II or D, accelerates to 20-25 km/h, passes through the short wave road at a speed of III or D, accelerates to 45-50 km/h, and sequentially passes through the left wheel curb impact road and/or the 30-degree angle obstacle road at a speed of V or D.

And (3) rapidly accelerating the test vehicle to 55-60 km/h on the No. 8 characteristic road, then rapidly braking and stopping, setting a steering zero position of the power steering system at a static state or a low speed, and accelerating the vehicle to exit after the vehicle is circulated for a plurality of times.

The No. 3 characteristic road comprises a twisted road, a bumpy road, a ditch road, a square pit and a uniform wave road which are sequentially arranged along the running direction of the test vehicle; the driving route of the No. 2 circulating path is as follows: the test vehicle passes through a twisted road at a speed of 10-12 km/h, passes through a bump road and a ditch road at a speed of 35-40 km/h, passes through a square pit at a speed of 45-50 km/h, passes through a uniform wave road at a speed of 50-55 km/h, and passes through a V-gear or a D-gear; the speed of 15-20 km/h is used for keeping the II gear or the D gear to pass through the rope road, the speed of 20-25 km/h is used for keeping the III gear or the D gear to pass through the manhole cover road, the saw tooth road, the sine obstacle and the cobble road edges on the left side and the right side in sequence.

The No. 4 characteristic road comprises a vibration road I, a concrete slab impact road, a fish scale pit and an inclined lane which are sequentially arranged along the running direction of the test vehicle, and the No. 6 characteristic road comprises a Belgium road, a splash water road, a vibration road II and a long wave road which are sequentially arranged along the running direction of the test vehicle.

The driving route of the No. 3 circulating path is as follows: the test vehicle sequentially passes through a vibration road I, a concrete slab impact road, a fish scale pit and an inclined lane at a speed of 35-40 km/h and keeps a gear IV or a gear D, then turns left to enter a steering test road, and then sequentially passes through a belgium road, a splash road and a vibration road II, and finally turns left to enter the steering test road at a speed of 50-55 km/h and keeps a gear V or a gear D to pass through a long wave road.

The left side of the vibration road I of the No. 4 characteristic road is provided with an opening, the opening is communicated with a sand road bend of the No. 5 characteristic road, after passing through a No. 3 circulating road, a test vehicle passes through the sand road bend at a speed of 35-40 km/h while keeping a gear IV or a gear D to pass through the vibration road I and turn left, the test vehicle runs straight and accelerates to 65-70 km/h for ABS emergency braking and stopping, after the test vehicle starts normally, the test vehicle leaves the No. 5 characteristic road and turns left to enter a steering test road, and after the test vehicle passes through a residential district anticlockwise, the test vehicle enters a city square by the No. 6 characteristic road.

After the power-assisted steering system is set at a static state or a low speed, the cyclic operation of 'small 8 words' and 'big 8 words' is sequentially completed in the city square, and then the setting of the steering zero position is continued.

The small 8-shaped cyclic operation is that a test vehicle dies a steering wheel at the corner of the city square, I gear, L gear or D gear is hung, and a plurality of 8-shaped driving routes are completed in the city square at the speed of 15-20 km/h.

The large 8-shaped circulating operation is that the center of a test vehicle is arranged on the center line of a city square, I gear, L gear or D gear is hung, and a plurality of 8-shaped driving routes are completed in the city square at the speed of 20-25 km/h.

The speed-changing circulation process is to carry out speed-changing circulation running at various speeds, so that the test vehicle can continuously run for a set distance by changing the speed after running for a set distance at one speed, and the circulation is completed to run in a multi-circle high-speed loop.

The driving mode comprises a standard mode, an economic mode, a sport mode, an off-road mode and a snowfield mode, the total number of the durable subcycles is 64, the mileage of the vehicle is 20250 km-20270 km, the standard mode carries out 32 durable subcycles, and the economic mode, the sport mode, the off-road mode and the snowfield mode respectively carry out 8 durable subcycles; after the automobile passes through 64 durable subcycles, the total mileage of the automobile on the reinforced durable road is 9000 km-9200 km.

In the step 4, the tire transposition includes transposition of front wheels and rear wheels on the same side of the vehicle body and transposition of front wheels and rear wheels on different sides of the vehicle body, after the front wheels and the rear wheels on the same side of the vehicle body are transposed, the high-speed loop is subjected to speed change circulation for a plurality of times, then the front wheels and the rear wheels on different sides of the vehicle body are transposed, and whether key electric devices are normal is checked after transposition.

The speed change cycle after tire transposition is the same as the speed change cycle process in the durable subcycle, and the high-speed cycle after tire transposition is to circularly run for a plurality of circles on the high-speed loop at the speed of 170-180 km/h so as to ensure the stability of the test vehicle.

The beneficial effects of the invention are as follows:

1. according to the invention, the driving test road comprising the reinforced durable road, the standard ramp area and the high-speed loop is constructed, so that the test vehicle can run in multiple complex road condition cycles through the reinforced durable road and the standard ramp area, the test vehicle can run on multiple types of road conditions and then enter the high-speed loop to carry out variable speed cycle running, the durability of all parts of the whole vehicle under multiple road conditions and multiple running speeds of the vehicle can be fully verified, and different driving modes can be subjected to corresponding times of durable subcycles according to the use requirements of users, so that the safety and reliability of the product can be effectively ensured due to the durable reliability of different power output when the vehicle uses multiple driving modes.

2. The traditional verification scheme is that the automobile runs once along a set route, the set route comprises different road conditions, in order to meet the requirement of a durability reinforcing test, the set site occupies a larger area, and the test cost is high; in addition, the invention enables the structural durability assessment of the vehicle to be closer to the use requirement by circulating running, wherein the circulating mileage of the reinforced durable road which is important for the durability test of the vehicle is larger than that of the conventional verification scheme, and the reliability of the automobile durability test is improved.

3. According to the invention, the standard mode, the economic mode, the sport mode, the off-road mode and the snow mode are used in one large cycle of the durability test, and according to the use requirement of a user, as the standard mode is the driving mode commonly used by the user, one half of the travel of the large cycle is operated by the standard mode, and the rest travel is equally divided by the other unusual economic mode, the sport mode, the off-road mode and the snow mode, so that the large cycle of the durability test has the durability test of multiple modes, meets the use requirement of the user, can verify the durability reliability of different power output when the automobile is used in multiple driving modes, and can effectively ensure the safety and reliability of products.

4. After the endurance sub-circulation of the set times is completed, the abnormal condition of the test vehicle is comprehensively checked and recorded, if the preset position is not abnormal, the front wheel and the rear wheel on the same side of the vehicle body are shifted and then are subjected to speed change and high-speed circulation, then the front wheel and the rear wheel on the different side of the vehicle body are alternately shifted, the endurance sub-circulation is continuously carried out after the normal operation of key electric devices is checked, the tires of the whole vehicle can be uniformly ground in, the running stability of the whole vehicle is ensured, the problems of shaking and directional deviation of the whole vehicle are avoided, and the reliability of the endurance test of the vehicle is further improved.

In conclusion, the test method enables the automobile to run circularly under the set multiple road conditions, can verify the durability and reliability of various parts of the whole automobile under the multiple road conditions and at multiple running speeds due to different power output when the automobile uses multiple driving modes, reduces test cost, ensures the reliability of test results and effectively ensures the safety and reliability of products.

Drawings

The contents of the drawings and the marks in the drawings of the present specification are briefly described as follows:

FIG. 1 is a schematic view of a driving test road according to the present invention;

FIG. 2 is a schematic diagram of the reinforced endurance road of FIG. 1;

FIG. 3 is a schematic view of the structure of the standard ramp region of FIG. 1;

FIG. 4 is a flow chart of a test vehicle route through a reinforced endurance road;

FIG. 5 is a schematic diagram of a test vehicle traveling in a shift cycle on a high speed loop;

the labels in the above figures are: 1. the road is characterized by comprising a reinforced durable road, a standard ramp area, a high-speed loop, a residential area, a city square, a No. 6.1 characteristic road, a No. 7.2 characteristic road, a No. 8.3 characteristic road, a No. 9.4 characteristic road, a No. 10.5 characteristic road, a No. 11.6 characteristic road, a No. 12.7 characteristic road, a No. 13.8 characteristic road and a No. 14 steering test road.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions in the embodiments will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present invention, and the following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.

The specific embodiment of the invention is as follows: a road test method for verifying the development of the durability of an automobile comprises the following steps:

step 1: as shown in fig. 1, a driving test road including a reinforced durable road 1, a standard ramp region 2, and a high-speed loop 3 is constructed, and the inside of the high-speed loop 3 is connected to the entrances of the reinforced durable road 1 and the standard ramp region 2 through a plurality of branches.

As shown in FIG. 2, the reinforced durable road 1 comprises a residential area 4 and a city square 5, the residential area 4 and the city square 5 are connected through a plurality of characteristic roads, the plurality of characteristic roads comprise a No. 1 characteristic road 6, a No. 2 characteristic road 7, a No. 3 characteristic road 8, a No. 4 characteristic road 9, a No. 5 characteristic road 10, a No. 6 characteristic road 11, a No. 7 characteristic road 12 and a No. 8 characteristic road 13, the No. 1 characteristic road 6 and the No. 7 characteristic road 12 form a No. 1 circulation path, the No. 3 characteristic road 8 and the No. 7 characteristic road 12 form a No. 2 circulation path, and the No. 4 characteristic road 9 and the No. 6 characteristic road 11 form a No. 3 circulation path. The two ends of the No. 4 characteristic path 9, the No. 5 characteristic path 10 and the No. 6 characteristic path 11 are respectively connected through a steering test path 14.

The characteristic road No. 1 6 comprises an S-shaped stone road, a concrete patch road and a mixed arch road which are sequentially arranged along the running direction of the test vehicle. The No. 2 characteristic road 7 comprises a railway road mouth, a vibrating road III, a prototype hollow road, a short wave road, a left wheel curb impact road and a 30-degree angle obstacle road which are sequentially arranged along the running direction of the test vehicle. The characteristic road No. 3 8 includes a twisted road, a bumpy road, a trench road, a square pit and a uniform wave road which are sequentially arranged along the running direction of the test vehicle. The No. 4 characteristic road 9 comprises a vibrating road I, a concrete slab impact road, a fish scale pit and an inclined lane which are sequentially arranged along the running direction of the test vehicle. The left side of the vibration road I of the No. 4 characteristic road 9 is provided with an opening which is communicated with the sand road bend of the No. 5 characteristic road 10. The characteristic road No. 6 11 includes a belgium road, a splash water road, a vibration road ii, and a long wave road, which are sequentially provided along the traveling direction of the test vehicle. The characteristic road No. 7 12 includes a rope road, a manhole cover road, a sine obstacle, and a pebble road, which are sequentially provided along the traveling direction of the test vehicle. The No. 8 characteristic road 13 includes an ABS braking road surface and an asphalt road sequentially provided along the traveling direction of the test vehicle. Each road condition of the reinforced durable road 1 is to carry out fatigue durability verification on a chassis structural member on a vehicle body bearing structure.

As shown in fig. 3, the standard ramp region 2 is provided as a mountain road, in which a standard slope of 15% and a standard slope of 18% are provided. The road section is used for mainly verifying the climbing performance, the parking performance and the hill start function of the vehicle.

Step 2: the test vehicle carries out multiple complex road condition circulation running through the reinforced durable road 1 and the standard ramp area 2, then enters the high-speed loop 3 to carry out variable speed circulation running, and the durable subcycle of the whole vehicle structure is completed. According to the invention, the driving test road comprising the reinforced durable road 1, the standard ramp area 2 and the high-speed loop 3 is constructed, so that the test vehicle can run in multiple complex road condition cycles through the reinforced durable road 1 and the standard ramp area 2, the test vehicle can run on multiple types of road conditions and then enter the high-speed loop 3 to run in a variable speed cycle, the durability of all parts of the whole vehicle under multiple road conditions and multiple running speeds of the vehicle can be fully verified, the corresponding times of durable subcycles can be carried out according to different driving modes, and when the vehicle uses multiple driving modes, the safety and reliability of the product can be effectively ensured due to the durable reliability of different power outputs.

Specifically, as shown in fig. 4, the test vehicle passes through the reinforced durable road 1 in the process of passing through the twice 1 # circulation path, the twice 2 # circulation path 7, the twice 8 # characteristic path 13, the twice 2 # circulation path, the twice 3 # circulation path, the twice 4 # characteristic path 9, the twice 5 # characteristic path 10, the residential area 4, the twice 6 # characteristic path 11 and the city square 5 in sequence, and is driven into the standard ramp area 2 by the city square 5.

Wherein, the travel route of No. 1 circulation way is: the test vehicle passes through the S-shaped stone road, the concrete patch road and the mixed arch road in sequence at the speed of 40-45 km/h, passes through the rope road at the speed of 15-20 km/h and keeps the II-gear or the D-gear, passes through the manhole cover road, the sine barrier and the snake-shaped pebble road in sequence at the speed of 20-25 km/h and keeps the III-gear or the D-gear. The road section belongs to a fatigue durability assessment road section, and the fatigue durability verification is mainly carried out on the chassis structural member.

The driving route of the No. 2 characteristic road 7 is as follows: the test vehicle is braked lightly and decelerated to 15-20 km/h by a railway road opening and a vibration road III at a speed of 35-40 km/h, accelerated to 20-25 km/h by a prototype hollow road by a gear II or a gear D, accelerated to 45-50 km/h by a short wave road by a gear III or a gear D, and sequentially passed through a left wheel curb impact road and/or a 30-degree obstacle road by a gear V or a gear D, and the test vehicle is in SUV type, and can directly pass through the 30-degree obstacle road without passing through the left wheel curb impact road. The road section belongs to a fatigue durability assessment road section, and the fatigue durability verification is mainly carried out on the chassis structural member.

The driving route of the No. 8 characteristic road 13 is as follows: the test vehicle is rapidly accelerated to 55-60 km/h on the No. 8 characteristic road 13, is rapidly braked and stopped, and is subjected to steering zero setting on the power steering system at a static state or a low speed, and is accelerated to exit after being circulated for a plurality of times. The road section carries out examination and verification on the braking performance and the steering performance of the vehicle.

The travel route of the No. 2 circulation path is as follows: the test vehicle passes through a twisted road at a speed of 10-12 km/h, passes through a bump road and a ditch road at a speed of 35-40 km/h, passes through a square pit at a speed of 45-50 km/h, passes through a uniform wave road at a speed of 50-55 km/h, and passes through a V-gear or a D-gear; the speed of 15-20 km/h is used for keeping the II gear or the D gear to pass through the rope road, the speed of 20-25 km/h is used for keeping the III gear or the D gear to pass through the manhole cover road, the saw tooth road, the sine obstacle and the cobble road edges on the left side and the right side in sequence. The road section belongs to a fatigue durability assessment road section, and the fatigue durability verification is mainly carried out on the chassis structural member.

The travel route of the No. 3 circulation path is as follows: the test vehicle passes through the vibration road I, the concrete slab impact road, the fish scale pit and the inclined lane in turn, then left turns to enter the steering test road 14, then passes through the belgium road, the splash road and the vibration road II in turn, and then passes through the long wave road at the speed of 50-55 km/h and keeps the V gear or the D gear, and then left turns to enter the steering test road 14. The road section belongs to a fatigue durability assessment road section, and the fatigue durability verification is mainly carried out on the chassis structural member.

The driving route from the No. 4 characteristic road 9 to the city square 5 is as follows: the test vehicle runs left through a sand road curve after passing through a vibration road I at a speed of 35-40 km/h, runs straight and accelerates to 65-70 km/h for ABS emergency braking and stopping, runs out of a No. 5 characteristic road 10 after normal starting, runs left into a steering test road 14, runs into a No. 6 characteristic road 11 after passing through a residential district anticlockwise, and runs into an urban square 5 from the No. 6 characteristic road 11.

The route running in the city square 5 is: after the power steering system is set in a steering zero position at a static state or a low speed, the cyclic operation of 'small 8 words' and 'big 8 words' is sequentially completed in the city square 5, and then the setting of the steering zero position is continued. Specifically, the small 8-shaped cyclic operation is that a test vehicle kills a steering wheel at the corner of the city square 5, i gear, L gear or D gear is hung, and a plurality of 8-shaped driving routes are completed in the city square 5 at the speed of 15-20 km/h. The large 8-shaped circulating operation is that the center of a test vehicle is arranged on the central line of the city square 5, I gear, L gear or D gear is hung, and a plurality of 8-shaped driving routes are completed in the city square 5 at the speed of 20-25 km/h. And (3) performing an 8-shaped test on the urban square, checking the steering and rollover stability of the vehicle, releasing the connection stress of the vehicle body structure, and evaluating whether the vehicle has abnormal sound.

Specifically, as shown in fig. 3, in the process that the test vehicle passes through the standard ramp area 2, the test vehicle runs close to the standard ramp bottom of 15%, starts from the ramp bottom, runs on the standard ramp, runs into the standard ramp of 18% after turning left, then runs down to the standard ramp bottom of 18%, and the vehicle runs into the open area of the ramp bottom, stops, and extinguishes and restarts. This cycle is repeated a number of times. The road section is used for mainly verifying the climbing performance, the parking performance and the hill start function of the vehicle.

Specifically, as shown in fig. 5, the test vehicle enters the high-speed loop 3 to perform the shift circulation travel by: the speed-changing circulation running is carried out at a plurality of speeds, so that the test vehicle can continuously run for a set distance by changing the speed after running for a set distance at one speed, the running of the multi-circle high-speed loop 3 is completed in the circulation, and the speed-changing/high-speed circulation test is mainly carried out by taking the durability, the gear shifting performance and the acceleration and deceleration performance of the power assembly into consideration.

Step 3: running endurance sub-cycles of corresponding times according to different driving modes, namely, the driving modes comprise a standard mode, an economic mode, a sport mode, an off-road mode and a snow mode, the number of the endurance sub-cycles is 64, the running mileage is 20250 km-20270 km, the standard mode carries out 32 endurance sub-cycles, and the economic mode, the sport mode, the off-road mode and the snow mode respectively carry out 8 endurance sub-cycles; after the automobile passes through 64 durable subcycles, the total mileage of the automobile on the reinforced durable road is 9000 km-9200 km.

According to the invention, the standard mode, the economic mode, the sport mode, the off-road mode and the snow mode are used in one large cycle of the durability test, and according to the use requirement of a user, as the standard mode is the driving mode commonly used by the user, one half of the travel of the large cycle is operated by the standard mode, and the rest travel is equally divided by the other unusual economic mode, the sport mode, the off-road mode and the snow mode, so that the large cycle of the durability test has the durability test of multiple modes, meets the use requirement of the user, can verify the durability reliability of different power output when the automobile is used in multiple driving modes, and can effectively ensure the safety and reliability of products.

The total mileage of the existing thirty-thousand comprehensive durability test is 30000 km, which comprises a mountain area road with 4000km, a reinforced durable road with 4000km, a common road with 4000km and a high-speed loop with 18000km, and the durability test of the automobile is that the automobile passes through the common road with 4000km, the high-speed loop with 18000km, the reinforced durable road with 4000km and the mountain area road with 4000km in sequence without running circularly. Different road conditions are set in the invention, the total mileage after 64 cycles is 20250 km-20270 km, and the total mileage of the reinforced durable road is 9000 km-9200 km. Thus, the present invention is superior to the conventional thirty thousand comprehensive durability test: 1. the area of the test field is reduced, and the test cost is reduced: the invention verifies each road condition in a circulating way, and the traditional three-ten-thousand comprehensive durability test is verified in a single form, and the circulating mileage number of the invention is reduced by 9000 kilometers compared with the total mileage of the traditional verification scheme, so that the test field area of the invention is reduced, the field construction cost is reduced, and the test cost is reduced. 2. The structural durability assessment of the vehicle is more reliable: the mileage of the reinforced durable road in the thirty-thousand comprehensive durability test is 4000km, and the total circulating mileage of the reinforced durable road is 9000 km-9200 km, which is increased by 5000 kilometers compared with the total mileage of the traditional thirty-thousand comprehensive durability test, so that the structural durability test of the vehicle is closer to the use requirement, and the reliability of the automobile durability test is improved.

Step 4: after the durable subcycles of the set times are completed, whether the preset part of the test vehicle is abnormal or not is comprehensively checked, the preset part of the test vehicle comprises a vehicle body, accessories, a power assembly, electrical equipment, a chassis and a system thereof and an engine room, the checking mode comprises checking appearance, whether a connecting piece is loosened, whether the work is normal or not, and the like, and whether the reliability and the durability of the preset part meet the design requirements or not is sequentially judged.

If no abnormality exists, after the front wheel and the rear wheel on the same side of the vehicle body are shifted, the high-speed loop 3 is subjected to speed change circulation for a plurality of times, namely speed change circulation running is carried out at a plurality of speeds, so that the test vehicle continuously runs for a set distance after running for a set distance at one speed, after the running of the multi-circle high-speed loop 3 is completed in the circulation, the test vehicle circularly runs for a plurality of circles on the high-speed loop 3 at a speed of 170-180 km/h, then the front wheel and the rear wheel on the opposite side of the vehicle body are shifted, and after shifting, whether key electric devices are normal is checked, so that the tires of the whole vehicle can be uniformly worn in, the running stability of the whole vehicle is ensured, the problems of shaking and directional deviation of the whole vehicle are avoided, and the reliability of the durability test of the vehicle is further improved. And continuing to perform the durable subcycle according to the methods of the step 2 and the step 3 until the abnormal condition occurs at the preset position in the test vehicle, wherein the reliability and the durability of the preset position are not in accordance with the requirements, and the abnormal condition is recorded.

The following examples further illustrate step 2 above:

1. test vehicle passing through reinforced durable road 1

1) Entering an automobile test field (shown in figure 1), firstly passing through an overpass of the test field at a proper speed, and reaching an enhanced durable road entrance guard for stopping.

The right turn entering the reinforced durable road 1 runs along the rotary island at a speed of about 30km/h and enters the No. 1 characteristic road 6, so that the uniform speed is 45km/h and the gear IV or D (manual gear IV and automatic gear D) is kept to run along the S-shaped stone road. Continuing to uniformly speed for 45km/h and keeping the gear IV or D (manual gear IV and automatic gear D) to pass through the concrete patch. And continuously and uniformly applying the speed to 45km/h, keeping the gear IV or D (manual transmission gear IV and automatic transmission gear D) to pass through the mixed arch road, namely finishing the running of the No. 1 characteristic road 6 and enabling the vehicle to exit, and entering the rotary island loop.

2) Traveling at a suitable vehicle speed along the rotary island and entering feature road 7 12. Gear II or gear D, passing through the rope road at a speed of 20 km/h. Properly accelerating, and keeping the III gear or the D gear to pass through the manhole cover road at the speed of 25 km/h. At a vehicle speed of 25km/h and maintaining either grade III or grade D through a sinusoidal obstacle. And (3) at a speed of 25km/h, keeping the III-gear or D-gear serpentine to pass through the pebble road, and requiring left-right steering for at least 8 times, namely finishing the running of the No. 7 characteristic road 12 and running out, entering the rotary island and running along the rotary island.

3) Repeating the steps 1) -2).

4) And driving into a No. 2 characteristic road 7, and keeping the III gear or the D gear to pass through a railway opening at a speed of 40 km/h. And the speed of 40km/h is kept at III or D and passes through the vibration path III. The vehicle is braked lightly and decelerated to 20km/h, and the vehicle passes through a prototype hollow road in gear II or gear D. Properly accelerating and passing through a short wave circuit at a speed of 25km/h with III or D gear. A moderate accelerator, accelerating to 50km/h, switching V gear or D gear, and impacting a road through a left wheel curb (only SUV vehicle type) at a vehicle speed of 50 km/h; and (3) maintaining the V gear or the D gear, and enabling the vehicle to pass through a 30-degree angle obstacle road at a speed of 50km/h, namely finishing the running of the No. 2 characteristic road 7 and enabling the vehicle to exit and enter a rotary island loop.

5) Traveling at a proper speed along the rotary island and entering a characteristic path No. 8 13. Rapid acceleration to 60km/h, and emergency braking and stopping on an ABS braking road surface. And the vehicle runs out of the ABS road to enter a right asphalt road, is rapidly accelerated to 60km/h, and is braked and stopped in an emergency. And 4 times of complete operation are executed, the dead direction is firstly beaten leftwards, the stop of the limit position is not more than 3s, then the dead direction is beaten rightwards, the stop of the limit position is not more than 3s, finally the steering wheel returns to the middle for 1 time, if the power steering of the vehicle is proper, the operation can be performed under the static state, and if the power steering of the vehicle is not performed, the operation can be performed under the low speed. Rapid acceleration to 60km/h, and emergency braking and stopping. And 4 times of complete operation are executed, the dead direction is firstly beaten leftwards, the stop of the limit position is not more than 3s, then the dead direction is beaten rightwards, the stop of the limit position is not more than 3s, finally the steering wheel returns to the middle for 1 time, if the power steering of the vehicle is proper, the operation can be performed under the static state, and if the power steering of the vehicle is not performed, the operation can be performed under the low speed. Accelerating and exiting feature number 8 road 13 into the rotary island.

6) Enter feature road 3 8 at a vehicle speed of 12km/h and keep gear I through the twist road. Proper acceleration, at a vehicle speed of 40km/h and keeping the IV gear through a bumpy road. Keeps IV gear and passes through the ditch road at the speed of 40 km/h. The gear is switched to V gear by proper acceleration, and the vehicle speed of 50km/h passes through 26 inch square pits. And (3) keeping the V gear, and enabling the V gear to pass through a uniform wave road at the speed of 55km/h, namely finishing the running of the No. 3 characteristic road 8 and enabling the V gear to exit and enter a rotary island loop.

7) Traveling at a suitable vehicle speed along the rotary island and entering feature road 7 12. At a vehicle speed of 20km/h and maintaining gear II through the rope path. Properly accelerating, and keeping the III gear to pass through the manhole cover road at the speed of 25 km/h. The same speed of the vehicle is kept at 25km/h and the III gears of the same gear pass through the saw-tooth road. Continue to pass the sinusoidal obstacle at the same speed 25km/h and same gear III. And continuing to drive to the edges of pebble roads at the left side and the right side in a snake-shaped mode at the same speed of 25km/h and the same gear III, and requiring a minimum of about 8 times of rapid direction switching until the vehicle completely passes through the pebble road, namely the No. 7 characteristic road 12 is driven out after the vehicle finishes driving, and enters a rotary island loop.

8) Repeating the above operation steps 6) -7).

9) And (4) entering a No. 4 characteristic road 9 at a speed of 40km/h and keeping the IV gear to pass through the vibration road I. The same speed of 40km/h and the same gear IV are kept to pass through the concrete slab impact road. And continuously passing through the fish scale pit at the same speed of 40km/h and the same gear IV. And (3) running along the left side, and enabling the vehicle to pass through an inclined lane at the same speed of 40km/h and the same gear IV, namely finishing running on the No. 4 characteristic road 9 and exiting, and entering a roundabout loop. And running to the port of the steering test path 14 according to the standard direction of the test field, entering the steering test path 14 after turning left, continuing to run according to the specified direction, entering the rotary island again and running along the rotary island.

10 A vehicle speed of 40km/h enters a No. 6 characteristic road 11 and keeps the IV gear passing through the belgium road. The same speed of 40km/h and the same gear IV are kept to pass through the splash water path. Continuously passing through the vibration path II at the same speed of 40km/h and the same gear IV. And (3) properly accelerating, and keeping the V gear to pass through a long wave path at a speed of 55km/h, namely finishing the running of the No. 6 characteristic path 11 and exiting, and entering a rotary island loop. And running to the port of the steering test path 14 according to the standard direction of the test field, entering the steering test path 14 after turning left, continuing to run according to the specified direction, entering the rotary island again and running along the rotary island.

11 Repeating the above steps 9) -10).

12 At a vehicle speed of 40km/h into the No. 4 characteristic road 9 and keep the IV gear passing through the vibration road I. Proper deceleration or parking and attention to view the left side rearview mirror, attention to the following test vehicle, ensure safe left turn into feature road number 5 10. And (3) turning on a hazard warning lamp, enabling the vehicle to pass through a sand road bend at a speed of 50km/h, enabling the vehicle to run straight and accelerate to 70km/h for ABS emergency braking and stopping, turning off the hazard warning lamp, enabling the vehicle to start normally and drive out of the No. 5 characteristic road 10, and enabling the vehicle to enter a rotary island loop. And running to the port of the steering test path 14 according to the standard direction of the test field, entering the steering test path 14 after turning left, continuing to run according to the specified direction, entering the rotary island again and running along the rotary island.

Stopping the vehicle when the vehicle runs to the intersection of the rotary island and the residential district, waiting until the test vehicle allows the vehicle to enter the residential district, after entering the residential district, driving anticlockwise to a turnout, switching gear to R gear, accelerating a moderate accelerator and reversing the vehicle to enter a ramp, stopping the vehicle after the front wheel completely enters the highest point of the ramp, switching into I gear, driving out of the residential district along anticlockwise defense line, and entering the rotary island loop.

And entering a No. 6 characteristic road 11 at a speed of 40km/h and keeping the IV gear to pass through the belgium road. The same speed of 40km/h and the same gear IV are kept to pass through the splash water path. Continuously passing through the vibration path II at the same speed of 40km/h and the same gear IV. And (3) properly accelerating, and keeping the V gear to pass through a long wave path at a speed of 55km/h, namely finishing the running of the No. 6 characteristic path 11 and exiting, and entering a rotary island loop. And continuing to travel along the rotary island, entering the city square, and parking the vehicle at the corner of the city square.

And 4 times of complete operation are executed, the dead direction is firstly beaten leftwards, the stop of the limit position is not more than 3s, then the dead direction is beaten rightwards, the stop of the limit position is not more than 3s, finally the steering wheel returns to the middle for 1 time, if the power steering of the vehicle is proper, the operation can be performed under the static state, and if the power steering of the vehicle is not performed, the operation can be performed under the low speed.

13 A dead steering wheel is driven, and I/L gear or D gear (manual gearbox, I gear is engaged; the automatic gearbox is put into L gear, if not, D gear is put into D gear, and the following steps are the same), 4 8-shaped operations are completed at the speed of 20km/h, namely the small 8-shaped cyclic operation is completed. The vehicle continues to run, meanwhile, the center of the vehicle is on a white line, I gear/L gear or D gear is hung, 4 8-shaped operations are completed at the speed of 25km/h, and the large 8-shaped circulation operation is completed. The vehicle exits around the 8-shaped area and is parked at the corner of the city square.

The vehicle runs along the roundabout loop and goes out of the reinforced durable road 1 according to the running direction required by the ground and goes out of the city square.

2. The test vehicle runs on the road surface according to the site specification requirement, and turns right to enter the standard ramp area 2.

1) After entering a standard slope, the test vehicle runs to the back of the slope at a proper speed, and is close to the standard slope bottom of 15%.

2) Starting from the bottom of a slope, accelerating with a full accelerator AT a first gear, stopping AT the middle part of the slope, tightening a hand brake, keeping for 5 seconds (CVT/AT is hung in L gear, AMT/DCT is hung in D gear, stopping AT the middle part of the slope, tightening the hand brake, CVT/AT/DCT is hung in P gear, AMT and MT are hung in N gear, releasing foot brake, and keeping for 5 seconds; CVT/AT/AMT/DCT manual mode reference MT).

3) The method comprises the steps of (1) engaging a first gear (AT, AMT, CVT, DCT engaging an L gear, engaging a D gear if the L gear is not available), driving a standard slope by a full throttle, turning left in a U shape, driving into an 18% standard slope (CVT/AT engaging the L gear and AMT/DCT engaging the D gear) under the condition that the 2-gear engine speed is allowed, stopping AT the middle part of the 18% standard slope, tightening a hand brake, and engaging a neutral gear (CVT/AT/DCT engaging the P gear); AMT, MT engaged N gear), releases the foot brake, hold for 5 seconds. (CVT/AT/AMT/DCT Manual mode reference MT).

4) The 1 st gear is engaged and continues to the bottom of the 18% standard grade (CVT/AT engaged in L gear, AMT/DCT engaged in D gear). CVT/AT/AMT/DCT manual mode reference MT), the vehicle is driven into an open area AT the bottom of the slope, stopped, flameout and restarted.

5) Repeating the above operations 1) to 4) three times, and performing the operations 1) to 4) four times in total.

6) The step 1-2 is that the whole vehicle is driven in a circulating way under a complex road condition.

The procedure 6) was repeated five times, i.e. six times in total.

3. After the above steps are completed, the test vehicle enters the high speed loop T7.

1) 4 cycles of 50/80 speed cycle were completed, i.e. 0.8km or 0.4km was alternately travelled at a speed of 50km/h and 80 km/h.

2) The 4-turn 80/120 speed cycle was completed, i.e., 0.8km or 0.4km was alternately traveled at a speed of 50km/h and 80 km/h.

3) Repeating the steps 1-3 to finish a durable sub-cycle of the whole vehicle structure.

All the above steps are completed as one large cycle, with 32 cycles of about 10133km using NORMAL, about 2533.25km for ECO, about 2533.25km for SPORT, about 2533.25km for OFF-ROAD, and about 2533.25km for SNOW.

According to the invention, the driving test road comprising the reinforced durable road, the standard ramp area and the high-speed loop is constructed, so that the test vehicle can run in multiple complex road condition cycles through the reinforced durable road and the standard ramp area, the test vehicle can run on multiple types of road conditions and then enter the high-speed loop to carry out variable speed cycle running, the durability of all parts of the whole vehicle under multiple road conditions and multiple running speeds of the vehicle can be fully verified, and different driving modes can be subjected to corresponding times of durable subcycles according to the use requirements of users, so that the safety and reliability of the product can be effectively ensured due to the durable reliability of different power output when the vehicle uses multiple driving modes.

The traditional verification scheme is that the automobile runs once along a set route, the set route comprises different road conditions, in order to meet the requirement of a durability reinforcing test, the set site occupies a larger area, and the test cost is high; in addition, the invention enables the structural durability assessment of the vehicle to be closer to the use requirement by circulating running, wherein the circulating mileage of the reinforced durable road which is important for the durability test of the vehicle is larger than that of the conventional verification scheme, and the reliability of the automobile durability test is improved.

After the endurance sub-circulation of the set times is completed, the abnormal condition of the test vehicle is comprehensively checked and recorded, if the preset position is not abnormal, the front wheel and the rear wheel on the same side of the vehicle body are shifted and then are subjected to speed change and high-speed circulation, then the front wheel and the rear wheel on the different side of the vehicle body are alternately shifted, the endurance sub-circulation is continuously carried out after the normal operation of key electric devices is checked, the tires of the whole vehicle can be uniformly ground in, the running stability of the whole vehicle is ensured, the problems of shaking and directional deviation of the whole vehicle are avoided, and the reliability of the endurance test of the vehicle is further improved.

The foregoing is provided by way of illustration of the principles of the present invention, and is not intended to be limited to the specific constructions and applications illustrated herein, but rather to all modifications and equivalents which may be utilized as fall within the scope of the invention as defined in the claims.

Claims

1. The road test method for verifying the development of the durability of the automobile is characterized by comprising the following steps of:

step 3: operating the durable subcycles corresponding times according to different driving modes; the driving mode comprises a standard mode, an economic mode, a sport mode, an off-road mode and a snowfield mode, the total number of durable subcycles is 64, the mileage of running is 20250 km-20270 km, the standard mode carries out 32 durable subcycles, and the economic mode, the sport mode, the off-road mode and the snowfield mode respectively carry out 8 durable subcycles; after the automobile passes through 64 durable sub-cycles, the total mileage of the automobile on the reinforced durable road is 9000 km-9200 km;

step 4: after finishing the durable sub-circulation of the set times, comprehensively checking whether the preset part of the test vehicle is abnormal, if no abnormality exists, continuing to perform durable sub-circulation according to the methods of the step 2 and the step 3 after the tire is transposed until the preset part of the test vehicle is abnormal, and recording the abnormal situation if the reliability and the durability of the preset part are not in accordance with the requirements; in the step 4, the tire transposition includes transposition of front wheels and rear wheels on the same side of the vehicle body and transposition of front wheels and rear wheels on different sides of the vehicle body, after the front wheels and the rear wheels on the same side of the vehicle body are transposed, the high-speed loop is subjected to speed change circulation for a plurality of times, then the front wheels and the rear wheels on different sides of the vehicle body are transposed, and whether key electric devices are normal is checked after transposition.

2. The road test method for verifying the durability development of an automobile according to claim 1, wherein: the inner side of the high-speed loop is connected with the reinforced durable road and the entrance of the standard ramp area through a plurality of branches.

3. The road test method for verifying the durability development of an automobile according to claim 1, wherein: the reinforced durable road comprises a residential area and a city square, and the residential area and the city square are connected through a plurality of characteristic roads.

4. The road test method for verifying the durability development of an automobile according to claim 1, wherein: the characteristic ways comprise a No. 1 characteristic way, a No. 2 characteristic way, a No. 3 characteristic way, a No. 4 characteristic way, a No. 5 characteristic way, a No. 6 characteristic way, a No. 7 characteristic way and a No. 8 characteristic way which are sequentially arranged, the No. 1 characteristic way and the No. 7 characteristic way form a No. 1 circulation way, the No. 3 characteristic way and the No. 7 characteristic way form a No. 2 circulation way, and the No. 4 characteristic way and the No. 6 characteristic way form a No. 3 circulation way.

5. The road test method for verifying the durability development of an automobile according to claim 4, wherein: the process that the test vehicle passes through the reinforced durable road sequentially passes through the No. 1 circulating path, the No. 2 characteristic path, the No. 8 characteristic path, the No. 2 circulating path, the No. 3 circulating path, the No. 4 characteristic path, the No. 5 characteristic path, the residential area, the No. 6 characteristic path and the city square, and the city square drives into the standard ramp area.

6. The road test method for verifying the durability development of an automobile according to claim 5, wherein: and the two ends of the No. 4 characteristic path, the No. 5 characteristic path and the No. 6 characteristic path are respectively connected through a steering test path.

7. The road test method for verifying the durability development of an automobile according to claim 5, wherein: the No. 1 characteristic road comprises an S-shaped stone road, a concrete patch road and a mixed arch road which are sequentially arranged along the running direction of the test vehicle; the No. 7 characteristic road comprises a rope road, a well cover road, a sine barrier and a pebble road which are sequentially arranged along the running direction of the test vehicle.

8. The road test method for verifying the durability development of an automobile according to claim 7, wherein: the running route of the No. 1 circulating path is as follows: the test vehicle sequentially passes through an S-shaped stone road, a concrete patch road and a mixed arch road at a speed of 40-45 km/h, passes through a rope road at a speed of 15-20 km/h, and passes through a manhole cover road, a sine obstacle and a snake shape at a speed of 20-25 km/h.

9. The road test method for verifying the durability development of an automobile according to claim 5, wherein: the No. 2 characteristic road comprises a railway road mouth, a vibrating road III, a prototype pothole road, a short wave road, a left wheel curb impact road and a 30-degree angle obstacle road which are sequentially arranged along the running direction of a test vehicle, the test vehicle sequentially passes through the railway road mouth and the vibrating road III at a speed of 35-40 km/h and keeps a gear III or a gear D, is lightly braked and decelerated to 15-20 km/h, passes through the prototype pothole road at a gear II or a gear D, accelerates to 20-25 km/h and passes through the short wave road at a gear III or a gear D, accelerates to 45-50 km/h and sequentially passes through the left wheel curb impact road and/or the 30-degree angle obstacle road at a gear V or a gear D.

10. The road test method for verifying the durability development of an automobile according to claim 5, wherein: and (3) rapidly accelerating the test vehicle to 55-60 km/h on the No. 8 characteristic road, then rapidly braking and stopping, setting a steering zero position of the power steering system at a static state or a low speed, and accelerating the vehicle to exit after the vehicle is circulated for a plurality of times.

11. The road test method for verifying the durability development of an automobile according to claim 5, wherein: the No. 3 characteristic road comprises a twisted road, a bumpy road, a ditch road, a square pit and a uniform wave road which are sequentially arranged along the running direction of the test vehicle; the driving route of the No. 2 circulating path is as follows: the test vehicle passes through a twisted road at a speed of 10-12 km/h, passes through a bump road and a ditch road at a speed of 35-40 km/h, passes through a square pit at a speed of 45-50 km/h, and passes through a uniform wave road at a speed of 50-55 km/h; and (3) keeping the gear II or the gear D to pass through the rope road at the speed of 15-20 km/h, and keeping the gear III or the gear D to pass through the manhole cover road, the saw-tooth road, the sine obstacle and the cobble road edges on the left side and the right side in sequence at the speed of 20-25 km/h.

12. The road test method for verifying the durability development of an automobile according to claim 6, wherein: the No. 4 characteristic road comprises a vibration road I, a concrete slab impact road, a fish scale pit and an inclined lane which are sequentially arranged along the running direction of the test vehicle, and the No. 6 characteristic road comprises a Belgium road, a splash water road, a vibration road II and a long wave road which are sequentially arranged along the running direction of the test vehicle.

13. The road test method for verifying the durability development of an automobile according to claim 12, wherein: the driving route of the No. 3 circulating path is as follows: the test vehicle sequentially passes through a vibration road I, a concrete slab impact road, a fish scale pit and an inclined lane at a speed of 35-40 km/h and keeps a gear IV or a gear D, then turns left and enters a steering test road, then sequentially passes through a belgium road, a splash road and a vibration road II, and finally turns left and enters the steering test road at a speed of 50-55 km/h and keeps a gear V or a gear D to pass through a long wave road.

14. The road test method for verifying the durability development of an automobile according to claim 12, wherein: the left side of the vibration road I of the No. 4 characteristic road is provided with an opening, the opening is communicated with a sand road bend of the No. 5 characteristic road, after passing through a No. 3 circulating road, a test vehicle passes through the sand road bend with the speed of 35-40 km/h and keeps the IV gear or the D gear to pass through the vibration road I in a left-turn mode, the test vehicle runs straight and accelerates to 65-70 km/h for ABS emergency braking and stopping, after the test vehicle starts normally, the test vehicle runs out of the No. 5 characteristic road and enters a steering test road in a left-turn mode, after the test vehicle passes through a residential district in a anticlockwise mode, the test vehicle runs into a city square by the No. 6 characteristic road.

15. The road test method for verifying the durability development of an automobile according to claim 12, wherein: after the power-assisted steering system is set at a static state or a low speed, the cyclic operation of 'small 8 words' and 'big 8 words' is sequentially completed in the city square, and then the setting of the steering zero position is continued.

16. The road test method for verifying the durability development of an automobile according to claim 15, wherein: the small 8-shaped cyclic operation is that a test vehicle dies a steering wheel at the corner of the city square, I gear, L gear or D gear is hung, and a plurality of 8-shaped driving routes are completed in the city square at the speed of 15-20 km/h.

17. The road test method for verifying the durability development of an automobile according to claim 15, wherein: the large 8-shaped circulating operation is that the center of a test vehicle is arranged on the center line of a city square, I gear, L gear or D gear is hung, and a plurality of 8-shaped driving routes are completed in the city square at the speed of 20-25 km/h.

18. The road test method for verifying the durability development of an automobile according to claim 1, wherein: the speed-changing circulation process is to carry out speed-changing circulation running at various speeds, so that the test vehicle can continuously run for a set distance by changing the speed after running for a set distance at one speed, and the circulation is completed to run in a multi-circle high-speed loop.

19. The road test method for verifying the durability development of an automobile according to claim 1, wherein: the speed change cycle after tire transposition is the same as the speed change cycle process in the durable subcycles, and the high-speed cycle after tire transposition is to circularly run for a plurality of circles on the high-speed loop at the speed of 170-180 km/h so as to ensure the stability of the test vehicle.