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recently, the controversy over the "elk test" has been raging. some say it is useful, some say it is useless, and some say it is rampantly faked. but the actual situation is that the "elk test" was wrong from the beginning!

"moose test" is a mistranslation

first of all, we need to correct a wrong translation. the english name of the "elk test" is "moose test". moose refers to "moose". of course, the swedes who first used this word called it "älgtest", so "elk" should actually be a misreading of the translation. the purpose of the test is very simple. it is mainly to test the maneuverability of the car when avoiding obstacles. later, this test was included in the iso standard and numbered iso 3888. the domestic national standard is gb/t recommended standard numbered gb/t 40521, and directly adopts iso 3888 standard. this is the standard source of a series of so-called "elk tests" in china.

among them, iso 3888 is divided into two parts, that is, two test standards.

part one: double lane shift.as the name suggests, you should try to keep the accelerator pedal stable, control the vehicle through the fixed roadblock line, and record the speed of the 5th stage of the test, which is the final result.

test purpose: analyze the time domain signal of steering input or body motion parameters; evaluate driving control strategy; subjective vehicle evaluation.

part 2: obstacle avoidance.manual transmission vehicles need to enter the test lane in the highest gear state; automatic transmission vehicles need to enter the test lane in d gear state. after entering the first section, release the accelerator at 2 meters until you exit the test lane.the vehicle speed at the end of the first section of the test track is recorded as the final result.

test purpose: to assess the vehicle's ability to avoid obstacles that suddenly appear in front of it.

however, the test standard also clearly states thatsince the vehicle's driving path is different each time the measurement is made, the vehicle speed obtained from multiple tests will be obviously discrete, even if the longitudinal process of the vehicle is strictly limited (i.e., releasing the accelerator at 2 meters in the first section),it is also not possible to obtain consistent speed data. therefore, there should be no speed-based grading, nor should there be a minimum speed for testing.

the test standard also has detailed provisions for the length and width of the test lane, as well as the translation distance of the obstacle avoidance line. the obstacle avoidance start area (phase 2) and the obstacle avoidance end area (phase 4) are 13.5 meters and 12.5 meters long respectively, and the total length of the entire test area is 61 meters. and from the above figure, it can be clearly seen that the offset of area b (obstacle avoidance area) relative to area a (obstacle avoidance start area) and area c (obstacle avoidance end area) is 1 meter.

this means that the left lane lines (i.e. test barrels) of stage 2 and stage 4 should be on the same straight line, while the right lane lines are generally different due to the difference in width. after all, the width of the test vehicles is different, so there are not many restrictions on the width of the right side.

of course, many domestic automotive media and companies, like european media, use the so-called "elk test" test standard, which is the national standard gb/t 40521, which is the second part of iso 3888 - obstacle avoidance. so it can be seen that even for a relatively simple "obstacle avoidance test", the 1-meter offset and the third stage of only "car width + 1 meter" are the difficulties of the entire test.

trick 1: confusing testing standards

usually, the most serious problems occur at this stage. as mentioned before, the left cone barrel in stage 2 and the right cone barrel in stage 3 need to be 1 meter apart (that is, the position of number 7). however, many actual test lanes cannot guarantee a spacing of 1 meter, so the vehicle offset is reduced, greatly reducing the difficulty of the test.

however, ordinary consumers hardly pay attention to the offset distance, nor do they go to the site to test the offset distance, so it is easy to fish in troubled waters. of course, many testers who do so will not claim that they strictly test in accordance with the "national standard gb/t 40521-2" or "iso 3888-2". however, for ordinary people and consumers who are not aware of the situation, it will cause great misunderstandings and misleading. for example,in the "elk test" shown above, is the offset of stage 3 1 meter? even the cones of stage 2 and stage 4 are not in a straight line.

there are even some companies that openly place cones almost in a straight line, a "moose test", such as the placement of the cones in the picture above.

in fact, this cone stacking method is the cone stacking position for the "double shift line" test.use the "double lane change" test lane to test the effectiveness of the "obstacle avoidance test"isn’t it funny? of course, it also shows that they are very smart. it is called the “moose test” and no one stipulates that the content of part 2 should be tested with part 1, right?

back to the "elk test" conducted by teknikens värld on the citroën xantia activa v6, the spacing of the cones, and the positions of the cones in stage 2 and stage 4. it is a completely standard test of "iso 3888-2".

trick 2: recording results arbitrarily

according to the "iso 3888-2" test standard, during the test, after entering the first stage for two meters, release the accelerator until the vehicle exits the test track. secondly, the vehicle speed at the end of the first stage of the test track should be measured and recorded in the test report.

however, in actual operation, when the vehicle enters the first stage, the tester can lift the accelerator and set the vehicle to sports mode or maximum kinetic energy recovery in advance. in this way, even if the brakes are not applied, the power recovery will cause the vehicle to slow down sharply, and it will successfully pass the third stage with a displacement of 1 meter. although the tire friction increases and the kinetic energy recovery force increases again, the vehicle speed will drop to a very low level at the end of the third stage and the beginning of the fourth stage, and the difficulty of vehicle control will be greatly reduced. in other words, although the brakes were not applied throughout the entire process, the strong power recovery mode is almost the same as the braking effect. moreover, the faster the initial speed of the vehicle, the greater the power recovery force when the accelerator is lifted.

in addition, according to the test standards, the speed at the end of the first stage of the test track should be recorded, but in actual operation, the speed when entering the first stage is usually recorded as the fastest speed. this can avoid the vehicle speed dropping suddenly due to strong power recovery, which affects the speed results during publicity.

for example, replacing the test vehicle with larger and wider tires, using a battery pack with smaller battery capacity and lighter weight, etc. can directly affect the results of the "elk test". and for ordinary consumers, the details here are completely unknown, and there are many means and methods that can be manipulated by humans, and they are very hidden.

"moose test"? watch it for fun

how should we correctly view the "elk test" of various media and car companies? first of all, from the content of the obstacle avoidance test of "iso 3888-2" and the national standard "gb/t 40521-2", it has been clearly pointed out that:

"the purpose of this maneuver is to enable the vehicle to alternately generate higher lateral accelerations in order to evaluate the vehicle's lateral dynamics."

"the obstacle avoidance emergency lane change operation is used to test the vehicle's ability to avoid obstacles that suddenly appear in front of it."

“since the vehicle's driving path is different each time the measurement is made, the vehicle speed obtained from multiple tests will be significantly discrete, even if the longitudinal process of the vehicle is strictly limited (i.e., releasing the accelerator at 2 meters in the first stage),it is also not possible to obtain consistent speed data. therefore, there should be no speed-based grading, nor should there be a minimum speed for testing.”

so this kind of test,the driver's steering strategy will have a significant impact on the test results. it is not appropriate to conduct objective measurements of vehicle dynamics related performance. only subjective evaluation is recommended.”

"iso 3888-1" and national standard "gb/t 40521-1" double lane change test, then it can test "emergency lane change maneuvers, which are used to reproduce the transient lane keeping ability during emergency closed-loop control in actual driving". and it can "analyze the time domain signal of steering input or body motion parameters", "evaluate driving control strategies", and "vehicle supervisor evaluation".

therefore, for most of the current "elk tests" in china, in most cases, we just need to watch the fun. if the tester advertises that the test process is strictly in accordance with the obstacle avoidance test standards of "iso 3888-2" or the national standard "gb/t 40521-2", then you can pay some attention to it. after all, the test results still have certain requirements for the basic quality of the vehicle, but don't pay too much attention to it, because there are countless hidden means that affect the test results. if the tester doesn't say anything, then you don't even need to look at the test results and just swipe away.

if the tester claims that they use the "iso 3888-1" or national standard "gb/t 40521-1" double lane change test, then we need to pay more attention to the test results. whether a car has excellent handling can be used as a critical reference. however, such tests are difficult to see around the world because of their poor results and higher requirements for vehicle quality. to put it bluntly, it is a group of profit-driven people who took advantage of the information gap and used a "trick" that can't even be considered a conspiracy to fool everyone.