Automotive Benchmarking Services

We provide our constantly updated passenger car benchmark database for your for your quick utilization. Also as per requirement, we conduct an On Demand Advanced Benchmarking activity on vehicles of your selection and parameters that are most important to you.

Benchmarking Brackets of carsOn Demand Advanced Automotive Benchmarking

The list of measurements covered under this umbrella or tests are here: Click here.

The Passenger Car Benchmark  Database

We benchmark the parameters which directly affect the perceived consumer experience. These measured parameters have been selected after extensive consumer feedback. We have then conducted measurements on more than 50 different models on sale in the country to create the most exhaustive and frequently updated database.

Parameters

We worked with average consumers, automotive enthusiasts, reviewers and engineers to identify the parameters to be covered. The following image depicts the process in detail –

Benchmark IMG3

This process narrowed down consumer expectations to the following parameters:

benchmark parameters NVH, comfort, safety

Out of these parameters, cost of ownership and after sales service are widely benchmarked across the world and in India to rank car manufacturers. Testing Safety of the car is in the scope of regulatory agencies in India and abroad. Hence our study has excluded these two parameters. Comfort and Performance affect the consumer in day to day life but are never benchmarked at large scale across the segments. We’ve broken these vital attributes into sub groups for measurement and comparison.

noise, vibration, comfort, effort, seat

The Process

car benchmarking process

 

Below is a more detailed insight in the process.

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Steering on steering? That’s a ‘steering torque and angle sensor’

1. Noise, vibration and harshness
2. Steering and pedal effort
3. Seat comfort and suspension efficiency
4. Acceleration and braking
5. Real world fuel efficiency
6. Air-conditioning efficacy

 

 

 

 

 

NOISE, VIBRATION AND HARSHNESS

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One of our Data Acquisition Systems – brain behind the tests.
A high-sensitivity microphone set up at 700 mm from the seat base and 50mm in front of the headrest (at ear level) to measure noise.
A high-sensitivity microphone set up at 700 mm from the seat base and 50mm in front of the headrest (at ear level) to measure noise.

What it measures: Commonly known as an NVH test, this measures the amount of noise you can hear in the vehicle – at the driver’s seat and at the passengers’ seats, which will also determine the level of comfort in a vehicle. The test also measures vibrations felt at various points in the vehicle, which are a major contribution to “driver fatigue” on a long trip. (Ever travelled in a rattling old state transport bus? It will give you an idea of what vibrations can do to you).

 

An accelerometer on the steering to measure steering vibrations across 3-axis.
An accelerometer on the steering to measure steering vibrations across 3-axis.
Live data being captured on the test engineer’s laptop. Note even the speed readings (61 kmph) also coming as well as the vibrations and noise levels from all the sensors in the car.
Live data being captured on the test engineer’s laptop. Note even the speed readings (61 kmph) also coming as well as the vibrations and noise levels from all the sensors in the car.

The testing equipment:

Data Acquisition system – This is the “brain” of the testing equipment

Connectors –Ensures no noise in the signal transmission

Microphones – These are high sensitivity microphones that are set up at just about ear level (always maintaining same distance from seat H point) near the driver’s seat and rear left passenger’s seat, and in the case of MUV/SUVs with three rows, they are set up at ear level in the third row too. These capture actual noise in the cabin just how the human ear would hear it.

Seat pad vibration sensor – These high sensitivity pads are set up on the seat to measure how much vibration filters through the seat – which means how much you would feel on your body. Seats with good cushioning usually insulate vibrations pretty well.

Uniaxial and triaxial accelerometers – These are attached to the steering, to the gear lever and on the floor to measure just how much vibration a driver will feel. Diesel engines for instance tend to throw up far more vibrations through the steering and gear lever than a petrol would generally.

Normal standards of measurement:
The actual output is measured in dBA (decibels A-weighted) which is the relative level of sound as perceived by the human ear. Up to 70 dBA is a comfortable, accepted noise level in a car when it is moving at about 80-100 kmph. For perspective, 115 dBA is how loud a truck’s air horn is, and anything over 120 dBA is painful. In general among premium hatchbacks, petrol variants have ambient noise levels below 60 dBA, when driving at normal speeds, while diesels are around that mark. The lower the dBA level the quieter the car.This test is also a measure of the “Articulation Index” or the level at which normal conversation can happen in a car without having to raise ones voice to overcome engine noise and wind noise in the cabin. Low frequency sound in the cabin, such as a ‘booming’ noise that happens when you drive at low rpm in a high gear and also high frequency sounds such as an over-revving engine, both affect your ability to have a comfortable conversation in the car.Vibrations are picked up by the accelerometers and the seat pad sensors – these vibrations are measured in metres per second-square. The measurements of noise and vibration are recorded to cover both city and highway driving conditions one would normally encounter.

What affects this test:
NVH tests results will vary from car to car considerably. The cars we use for the test usually don’t have more than 15,000 km on them and are in stock condition – the way they are made by the OEM. NVH results can get affected by aftermarket tyres, suspension modifications and even with seat covers or extra carpeting in the car. The thickness of the seat cushion, the type of door beading (single or double layer) and even the thickness of the roof liner or door pads will affect the readings of this test. Hence, cars that have much thicker roof liners, seats and better quality door beadings are usually the quieter ones. This is one of the reasons car manufacturers give you a padded engine cover (also known as an NVH cover) to reduce noise especially with diesel engines.

The tabulation of results:
Now for a consumer the frequency graphs and numbers visible on the laptop screen would make little sense. There are just too many figures getting churned out every second. However, what our team does it to analyse that data and compare it with data from other cars in the same segment. This gives a car a relative score on a 0-100 scale. For example, car Y scored a 70 on NVH for the driver (the noise the driver can hear). Car Z, surprisingly, proved to be quieter – with a figure of 60 for the driver. The actual dbA levels against a particular RPM or vibration levels at certain RPM can also be recorded – this data is of immense value to car manufacturers. But for you, the car buyer, you just need to look at the relative score for each car.

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The various sensors (seat pad sensor – 3 axis, floor vibration sensor, gear lever vibration sensor, steering vibration sensor) pick up the vibrations felt in the vehicle body at various rpm (in this case the frequency of the vibration change at different RPM).

NVH Comparison of Cars

Since this data would mean nothing to the average consumer, our team does the number crunching to give you a rating on a 0-100 scale, where lower the figure is better. The Car Y, for example, scored 70 for the driver on noise, and 20 on vibration, while the Car Z scored 60 on noise for the driver and 25 on vibration. For the passenger the Car Y scored 78 on noise and 10 on vibration, while the Car Z scored 50 on noise and 18 on vibration. If you look at these relative scores, the Car Z is perceivably quieter than the Car Y under test conditions.

STEERING EFFORT AND PEDAL EFFORT TEST

What it measures: This test measures the effort required to turn the steering from lock to lock – when the car is stationary and also when the car is in motion. It lets you know just how much effort it would be to park a car. It also measures how many turns it takes to turn from full left to full right (lock-to-lock).

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Steering torque & angle sensor
Pedal effort sensor attached to the clutch pedal. Also seen is a Bluetooth OBD-II reader attached to the car's ECU port
Pedal effort sensor attached to the clutch pedal. Also seen is a Bluetooth OBD-II reader attached to the car’s ECU port

 

The test also measures how much effort it takes to press the clutch. This is an important factor given the bumper-to-bumper traffic conditions you face in many cities. Some cars really have hard clutches, which could lead to leg pain and fatigue in city driving conditions.

The testing equipment: Here’s what the set up consists of:

Steering torque and angle sensor: The second steering that is fitted on top of the car’s original steering is actually a steering torque and angle sensor. What it does is measure the effort (or torque) required to turn the steering wheel.

Pedal force sensor: The second piece of equipment used is a pedal force pressure sensor. It measures the effort it takes to press the clutch.

Gear lever force sensor: This is a sensor that sits parallel to the gear knob and senses the effort (in KgF) that the driver has to use to change the gear.

What affects this test:
The steering effort and clutch effort tests are greatly affected by the condition of the vehicle. Which is why, for our tests, all the vehicles tested have below 15,000 km on the odometer – so that normal wear and tear is not a significant factor affecting the test. Also the kind of steering – whether it is electronic power steering or a hydraulic power steering – also matters. Electronic power steering units take far less effort to turn compared to hydraulic power steering equipped cars.Similarly, for clutch effort – cars with a hydraulic clutch usually feel slightly heavier compared to smaller cars with cable operated clutches. But here too, the design of the clutch is important.
The tabulation of results:
Steering effort at parking speeds and in slow-speed city traffic is noted as mentioned in Newton Metres. The average of five readings is taken as the final reading – and this is compared with other cars in its segment. If the reading falls above the segment average, the car has a “heavy” steering and if it falls at or below the segment average, the car has a “light steering”.

The same measurement is done for clutch pedal effort as well. The average of the segment is taken and a car’s clutch can then by scientifically proven to have a “heavy” clutch or “light” clutch. The effort to shift gears is also measured in KgF.

An example:

In the CAR Y for instance, the lock-to-lock turns took a 450 degree angle with an approximately 6 Nm amount of torque needed. The spikes in torque are when it hits the bump stops. In relative score, the Car Y scored 30 while the Car Z scored 33 – both with relatively well-weighted power steering systems, with the Car Y requiring marginally less effort.

 

SEAT COMFORT AND SUSPENSION EFFICIENCY

What it measures: Ever wondered why some cars give you a backache when you drive long distances? This test measures exactly that. It also measures just how efficient the car’s suspension is, which greatly affects ride quality over bad roads and, as is measured in the test, when a car goes over a speed breaker (the bump test).

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The seat pressure mapping sensor placed over the seat measures exactly how much pressure the seat is exerting on the driver’s back and lower body. Each of the squares is a sensor that generates a heat map.
The standard-size speed breaker test measures vertical movement felt by the passenger in the car.
The standard-size speed breaker test measures vertical movement felt by the passenger in the car.

 

 

The testing equipment: This uses a highly specialized membrane placed on the seat along with triaxial accelerometers to measure movement along three axes, as the car moves over bumps.

Seat pressure mapping membrane: To measure seat comfort we use a highly sophisticated seat pressure mat that is placed over the seat. This membrane has many 1 cm2 squares on it, which measures the pressure the seat exerts on a driver’s back.

Accelerometers: Triaxial accelerometers are placed on the floor, dashboard and steering to measure the impact of bump on the tactile points.

Speed breaker: A standard size rubber with plastic coated speed breaker of 50 mm height and 350 mm width (the standard yellow and black speed bumps you see on city streets) is used to simulate the bump test for the car.

 

 

The normal standards of measurement:
The pressure exerted on a driver’s back, hips and thighs when he sits on a seat is measured in Kg/cm2. The seat is adjusted at the optimum driving position for such a driver, such that he gets a proper view of the road and can press the pedals comfortably.

Vibrations, when the car goes over a speed breaker are measured in metres per second-square. What is tracked is the vertical movement (along the Z-axis), to see how much of a jolt passengers in the car will get, when the car is driven over a speed breaker (50 mm high and 350 mm wide) at fixed speed.

What affects this test: The seat comfort test can be greatly affected by the quality of the car’s seat covers, the density of foam in the seat, the angle of incline of the seat (different drivers have different seating postures).
Suspension test is affected by the size of the tyres, the tyre pressure and the overall type of suspension the car has.

The tabulation of results:
Since there is so much data – we give you a single figure by crunching the numbers and averaging out the pressure distribution points and the peak pressure points. This is on scale of 0-100, where the lower the score, the better the seat.
Similarly, for the suspension efficiency test, the deviation on the Z-axis is measured and averaged out across the segment. On a score of 0-100 the lower the value, the more efficient the suspension of the car.

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The pressure map generated by the seat pressure sensor in various cars.
The graph shows the deviation along the Z-axis (vertical movement) for a car going over a speed breaker at 20 kmph, measured by the seat pad vibration sensor on the rear seat.
The graph shows the deviation along the Z-axis (vertical movement) for a car going over a speed breaker at 20 kmph, measured by the seat pad vibration sensor on the rear seat.

 

The lower portion is the one that shows the driver’s back against the seat, while the upper portion shows his lower body and thighs. Areas of red indicate high pressure areas – this could lead to pain and fatigue in the long run.

An example:

Suspension test: Again just putting out this graphical data would make no sense for a user. Hence an absolute number on a 0-100 scale, where lower is better, is given. In the bump test for example, the Car Y showed it was better than the Car Z with a score of 15 for the driver, compared to 22 for the Car Z. For rear seat too, the Car Y scored 24 compared to 35 for the Car Z, showing the Car Y has a much better ride quality than the Car Z.
Comfort test: Similarly, when measuring the seat comfort between the Car Y and the Car Z, it was found that the Car Y scored 22 for driver and 28 for rear seat passenger. Car Z is a little more bumpy for the driver with a score of 26, but is as comfortable in the rear seat as the Car Y with a score of 29.

 

ACCELERATION AND BRAKING TEST


What it measures: As the name suggests, this test measures just how fast a car can go from 0-60 kmph and 0-100 kmph. It also measures how much time and distance it takes for the car to come to a complete standstill from 100kmph to 0kmph.

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The inertial measurement unit with GPS that measures the velocity of the vehicle.

The testing equipment: This test uses a combination of an OBD device, GPS and an inertial measuring device.

Inertial measurement unit with GPS – this device is attached to the car’s dashboard, with a clear view of the sky to lock on to the GPS. It measures the acceleration at a high sampling rate.

The normal standards of measurement:
The IMU (inertial measurement unit with GPS) and OBD reader are connected to the car. Five runs with 150 Kg total payload(including occupants) are conducted to measure acceleration from standstill on a 2 kilometre stretch of tarmac. This averages out for differences in gear shifting patterns. Acceleration is measured seconds against kmph (0-100 in X seconds).
For braking, five trials of braking the car from 100 kmph to standstill (hard braking) are conducted on normal tarmac with a 150 kg payload.What affects this test:
Acceleration and braking can be affected by the type of tyres that the car has, the tyre pressures, the condition of the car’s clutch and also the driver’s gear shifting patterns. This is why an average of five runs is taken. For braking, whether the car has ABS or not also greatly affects the test.Tabulation of results:
The acceleration figures are fairly straight forward. By averaging out the best of five runs, you get the time taken in seconds to go from 0-100 kmph. Similarly for braking, the distance is measured from the exact braking point to the point where the car comes to an absolute standstill. And the time for the same is also measured. Generally, cars with lighter kerb weight and bigger brakes are better.

FUEL EFFICIENCY TEST

What it measures: This is a measure of real-world fuel efficiency of a car. It takes a slightly different testing approach that is more accurate than even the tried-and-tested tankful to tankful method of measuring fuel efficiency. Here a “Test cycle” is developed for various conditions and different cities – the car is driven in simulated bumper-to-bumper traffic conditions, moderate traffic conditions and at highway speeds, to get different fuel efficiency readings for these conditions.

Testing equipment:

Fuel Flow Meter: This device is attached to the direct and return fuel line of the car and this data is recordedin thedata logger. It measures real-time fuel consumption with high sampling rate and efficiency (from the fuel flow rate), under different driving conditions.

The normal standards of measurement:
Fuel efficiency is measured in kilometres per litre. With this cycle test, a large amount of data of the exact kmpl a car is giving at different speeds is generated. This is compared with the standard “claimed” fuel efficiency figure of the car maker.

What affects the test:
The weight of the people on board and the luggage in the car affects the test. So does tyre pressure. Therefore to keep it consistent, the car runs with about 50% to 60% fuel on board, with a payload of 150 Kg (that is 2 average people and about 30 Kg of luggage). Plus the test can vary with time of the day and traffic conditions. It varies from route to route.

How it is measured:
The car is driven in three different cycles. The first is in bumper-to-bumper traffic (this is done on an empty road, but simulated bumper-to-bumper conditions) for about 40 minutes. This means the car is driven in only 1st and 2nd gears at less than 20 kmph speed, with constant stops and idling for about 2 minutes each before moving again. The second test is in moderate traffic conditions. It is driven for about 50 minutes of speeds up to 40-50 kmph, with 2 minute stops every 10 minutes. The third is a highway cycle, where the car is driven between 60-100 kmph for about 20 minutes, with moderate gear changes.

Tabulation of results:
The data is captured and the average fuel efficiency for each of the driving cycles is measured in kilometres per litre.

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