2024.03.11 Hyundai Motor Group

Mojave Proving Ground, a place where cars are tested with a passion as hot as the desert

Hyundai Motor Group
There are no shortcuts to building a good car. All you can do is find problems and improve them as best you can. This is why Hyundai Motor Company/Kia puts its cars through extreme testing conditions.

In California City, west of the Mojave Desert, in the driest land in the western United States, lies Hyundai/Kia’s California Proving Ground (hereafter referred to as the Mojave Proving Ground). This is where the outstanding performance and high quality of Hyundai/Kia’s electric vehicles, which have been honored with automobile awards around the world, come together.

Hyundai IONIQ 5 N driving on the Mojave Proving Ground

Today’s cars are a combination of many different technologies, including mechanical, electrical, and electronic engineering. With such a significant increase in the number of components that make up a car, ensuring high quality requires rigorous testing beyond real-world road conditions. This is to discover and solve problems that computer simulations can’t, and to improve technical perfection.

Things look serene, but the ground temperature at the Mojave Proving Ground can reach over 54°C in the summer

Hyundai/Kia built the Mojave Proving Ground in 2005 in search of the most extreme conditions. The area has a desert climate and is extremely dry. In summer, the average temperature is 39℃ and the ground temperature exceeds 54℃. On the other hand, in winter, the weather is mild with an average of 26℃, but when storms come, it rains and freezes. As such, the Mojave Proving Ground allows for testing in a wide range of conditions.

The area of the Mojave Proving Ground is approximately 17.7 million ㎡. It’s one of the largest in the United States

The Mojave Proving Ground covers an area of approximately 17.7 million ㎡. It has 12 test tracks, including an oval, a vehicle dynamics area, and an uphill track, and if all test routes are extended, the length will reach a whopping 61 km. In the United States, similarly-sized proving grounds are only owned by global automakers such as GM, Ford, and Toyota. 

Sungyop Lee, Vice President of the Hyundai America Technical Center, Inc. (hereinafter “HATCI”), explained the main tests performed at the Mojave Proving Ground

Local compliance testing, testing to North America’s legal standards, durability testing, and material environmental testing are conducted at the Mojave Proving Ground. While introducing the Mojave Proving Ground, Sungyop Lee, Vice President of HATCI, explained as follows. 

“There are five main types of testing we do here. The local conformity test covers marketability-related areas such as ride comfort, steering stability, and noise, while the testing to North America’s legal standards covers safety-related performance such as vehicle rollover, braking distance, and accident avoidance speed. The durability test measures the car’s performance on various road surfaces, and the material environment test measures the durability of components in extreme weather conditions. We also focus on off-road driving and traction for SUVs that are popular in the North American market.”

Testing SUVs for off-road driving and towing is also a focus at the Mojave Proving Ground

At the Mojave Proving Ground, researchers from around the world, including HATCI, continue to test. Approximately 300 vehicles are tested annually, and the distance traveled on not only the test site, but also various locations in the United States, averages 200,000 km. The Mojave Proving Ground is the result of Hyundai/Kia’s commitment to providing safe mobility in any environment. This is also a driving force behind the company’s North American and global sales growth, and the foundation of their success in the EV and SUV markets.

Keeping electric vehicles cool in the hot desert

As the global automotive market is rapidly transitioning to electrification, Hyundai/Kia is among the most successful companies in this transition. In particular, Hyundai Motor Group’s dedicated E-GMP-based EV models have been well received in markets around the world. 

Hyundai Motor Group’s dedicated E-GMP-based EV models are highly perfected

The popularity of Hyundai/Kia’s electric vehicles is due to their perfection. The requirements to perfect an electric vehicle are different from cars with an internal combustion engine. Electric vehicles have denser batteries, which add more than 300 kg of weight compared to internal combustion engines. The key evaluation factor is whether the suspension, tires, and body can withstand these loads placed on them. Moreover, managing the heat generated by high-voltage batteries and motors that spin at more than 10,000 revolutions per minute is also an important evaluation factor.

Thermal management technology for electric vehicles is an essential challenge to achieve high perfection

Hyundai/Kia is actively utilizing the Mojave Proving Ground to test thermal management performance in extreme environments. Electric vehicle thermal management and cooling performance tests are conducted intensively on days with temperatures above 45°C and solar radiation exceeding 1,000W per square meter. Sungyop Lee, Vice President explained the electric vehicle performance test as follows.

“Electric vehicles are heavier than internal combustion engine cars, so driving performance tests such as ride and steering stability are very important. We also test charging, discharging, mileage, thermal management, and other characteristics that are unique to electric vehicles at the Mojave Proving Ground. This is a test of many new technologies related to electrification in the era of electric vehicles.”

At the Mojave Proving Ground, cooling performance is tested under a variety of conditions, including towing of electric vehicles

Hyundai/Kia has increased the intensity of its thermal management and cooling performance testing in the era of electric vehicles. This is to improve cooling performance and optimize the thermal management system to avoid excessive heat being generated in the motor or battery system under harsh driving conditions such as trailer towing, uphill driving, high-speed driving, and winding. 

The IONIQ 5 N has completed its cooling performance at the Mojave Proving Ground to ensure it performs well in harsh driving conditions

In the case of the IONIQ 5 N, for example, a key goal during development was to ensure that the battery temperature was controlled to not exceed 60°C, even in harsh driving conditions. After countless rounds of fast charging and driving at the Mojave Proving Ground, the conflicting goals of efficient energy management and maximizing driving performance were achieved. 

Efforts to improve performance continue outside of the Mojave Proving Ground. The entire continental United States is a testing ground for Hyundai/Kia. Last year, research engineers at Mojave Proving Ground spent nearly 10 weeks optimizing the battery safety and thermal energy management of electric vehicles in a variety of environments in the United States, including Death Valley, Minnesota, and Oregon.

Harsh driving tests to perfect electric vehicles

The Mojave Proving Ground from the sky Several test tracks to help perfect cars stand out

Performance testing of electric vehicles naturally includes an oval. This is a 10.3-km-long, oval, three-lane track that simulates an American highway. It is the largest test track at the Mojave Proving Ground and can conduct tests driving at 200 km/h. In fact, it’s so large that it takes three minutes to complete a lap.

To pass the test, a driver must complete more than 4,000 laps of an oval capable of reaching speeds of 200 km per hour without issue

New cars undergo a rigorous comprehensive endurance test on an oval. Over an average period of three months, the vehicle is driven at high speeds to measure its aging. At the same time, the drivetrain performance, wind noise, and other tests are evaluated. Each car is tested for 48,000 km and must complete more than 4,000 laps without incident to pass the test.

Various off-road test courses help evaluate the durability of different parts of the vehicle, such as the underbody impact

The Mojave Proving Ground has a number of track surfaces to evaluate the durability of electric vehicles with underbody batteries. The durability of the underbody of the vehicle is evaluated on a total of 16 types of track surfaces, including fixed tracks, uphill tracks, and off-road tracks, considering various external road conditions.

Kia Telluride driving on an off-road course

The durability test track is so harsh that driving just 16,000 km on it has the same effect as driving 160,000 km on regular roads. In particular, the twisting track surface is harsher than in the real world, which has a significant impact on battery and vehicle durability. Hyundai/Kia performs around 500 test drives here to ensure extreme durability.

Durability of parts that can withstand even extreme environments

Hyundai/Kia is taking advantage of the hot weather at the Mojave Proving Ground to test how each part of its cars is affected by the heat. The Material Weathering Facility measures the impact of sunlight and solar heat on parts of the car. It lists the many parts that make up a car, from exterior parts like bumpers, headlamps, and paint samples to interior parts like autonomous driving sensors, dashboards, and seats. These are exposed to extreme conditions for long periods of time to see how colors and materials deteriorate.

Panels displaying parts move with the sun’s position, creating harsher test conditions than in the real world

“The panel on which the parts are displayed moves according to the position of the sun and is constantly facing the sun during the day, which allows us to verify durability up to 30 times faster than strain testing in other regions,” said Youngjun Yoon, a senior research engineer on the Durability Test and Operations Team at HATCI The harsh test, which exposes the equivalent of an entire year’s worth of sunlight in just a few months, ensures that the panels can withstand extreme conditions. 

Tests to build electric cars that run well and are quiet

Ride and Handling (R&H) is critical to building a car that drives well. At the Mojave Proving Ground, research engineers are testing electric vehicles on a variety of tracks to evaluate their ride and handling, including the vehicle dynamics area, the special surface track, and the handling test track. 

The handling test track is a great way to ensure a car’s stability on the high, rugged and mountainous terrain of the United States. With a total length of 5 km, it consists of sharp curves and an 8% slope hill, allowing intensive tests of the car in marginal situations such as entering a corner at high speed and exiting at high speed. This leads to stable driving performance even on Korean roads with mountainous terrain.

Hyundai Avante N (Elantra N) driving on the Mojave Proving Ground
The uphill track, with its steep incline, is used to test the uphill driving performance of drivetrains

The 5.3-km-long uphill track with a slope of 2 to 12% is primarily used to test the drivetrain’s uphill driving performance. It’s the perfect place to test the high torque of an electric vehicle. Research engineers test the acceleration of electric vehicles by repeatedly stopping and starting the vehicle on the sloped track.

Special surface track at the Mojave Proving Ground

Electric vehicles driven by motors have no engine noise, so external noise has a greater effect. As such, Hyundai/Kia is focused on reducing noise as much as possible in various road environments and driving situations. The Mojave Proving Ground’s special surface track replicates a variety of real-world road conditions on U.S. roads. As roads in North America are characterized by a variety of pavement types, a variety of pavement types have been applied throughout the entire section to reflect this. 

The special surface track using various paving types in North America makes it easy to check noise while driving

Furthermore, North American roads are heavily coated with slurry seals to help the asphalt pavement last longer in sunny climates. As a result, the road surfaces are rough and create a lot of minor vibrations when driving. There is also a lot of noise generated while driving, due to things like roads weathered by wind, rain, and sun, bumps from driving over cracked asphalt, railroad crossings, manhole covers, etc.

Hyundai/Kia conducts U.S. compliance evaluations on a special surface track that replicates 30 different road conditions in New York, Detroit, Denver, San Francisco, and other U.S. cities, as well as a test track that replicates the “LA Freeway,” a representative main road in Los Angeles. The goal is to minimize noise, increase the car’s shock absorption, and reduce the amount of vibration that reaches the passengers to create a smooth ride. 

The Mojave Proving Ground evolves to keep up with global trends

Evolution is another characteristic of the Mojave Proving Ground. Global customer demands and market conditions are constantly changing. In response, facilities are improved and added to accommodate more rigorous testing. Matthew R. Seare of HATCI, who has been at the Mojave Proving Ground for 20 years and is in charge of operations and management, explains as follows.

“We continue to introduce new tests as technology evolves,” said Matthew R. Seare, Manager of Operations, Durability Test and Operations Team, HATCI

“As technology advances, we’re constantly introducing new tests that didn’t exist 20 years ago. It’s a major challenge to build and maintain a variety of test tracks and research facilities according to each environment. At the Mojave Proving Ground, we’re working hard to preserve the desert’s natural beauty while conducting tests for the future.”

Hyundai/Kia’s models passing through an off-road test track. Off-road performance is critical in North America

When the Mojave Proving Ground was completed, it had only one off-road test course. At the time, the focus was on simulating city and highway driving on paved tracks. Today, the Mojave Proving Ground has seven off-road courses, with more under construction. The goal is to create a car that can cope with any environment, in line with the global SUV trend. Heejin Kang, a senior research engineer at HATCI, explained as follows.

Hyundai Santa Fe passing through a rock gate

“The Mojave Proving Ground has added a variety of tests since its establishment. In the past, the main program was heat endurance testing for internal combustion engines, but now it has expanded to include driving and durability testing for electric and eco-friendly vehicles, off-road testing for SUVs, and more. The tests are changing as fast as the trends in the automotive industry are.”

Cars are being built in harsher environments than the roads they will travel with the customer

The United States offers many opportunities for off-road driving and a variety of environments. This is why it’s important to verify a wide range of conditions in environments that are harsher than the roads the customer will drive on to ensure robust performance. “In addition to the existing unpaved test tracks, the off-road test has added various track surfaces to strengthen the verification of various external environmental conditions,” explained Kyungjae Lee, a senior research engineer on the Chassis and Thermal Performance Test Team at HATCI. He also added, “We’re building powerful SUVs that can meet the needs of customers in line with the global trend of camping and other outdoor activities.”

Technology honed on off-road tracks lead to safety for everyone

Off-road testing isn’t just for SUVs. It also leads to ensuring that the technology is safe for everyone. Traction control system (TCS) testing is a good example of this. 

Boosting the performance of a traction control system (TCS) in off-road environments

The TCS is an essential off-road feature that allows a car to easily navigate over bumps and potholes by concentrating driving force on the grounded wheels. Hyundai/Kia has prepared a variety of track surfaces, including sandy tracks, gravel tracks, and asphalt berms, to test the TCS. This is a test stage to develop off-road driving performance and improve the performance of the TCS at the same time. This is an explanation from Lance McLaws, a senior research engineer on the HATCI Chassis and Thermal Performance Test Team. 

Lance McLaws, a senior research engineer on the HATCI Chassis and Thermal Performance Test Team, is responsible for evaluating and tuning off-road driving performance

“I’m in charge of evaluating and tuning overall off-road driving performance, including driving force control in low-speed off-road driving situations and controlling wheel slip (occurs when a stronger force than grip is applied to the wheels). We’re also testing our cars on some of the toughest off-road surfaces. You’ll be surprised to learn just how much an SUV like the Kia Telluride can climb steep inclines and rocky roads.” 

Kia Telluride getting through an off-road track

Off-road tests like this are not just for SUVs. An electric vehicle with an electric motor that produces near full torque instantly when it kicks in show excellent performance on even off-road tracks. However, because the power is transferred so quickly, they are prone to wheel slip, which is when the wheels slide. To control this, the TCS needs to be refined. Senior research engineer Lance McLaws showed his pride in his work.

TCS technology improved on off-road tracks help customers drive safer

“At HATCI, we tune both software and hardware for a myriad of aspects including design and regulations. There are many examples of tuning to make a car more stable over specific obstacles or off-road environments, and improving driver safety. Wheel slip control, which is part of my job, may be a secondary feature, but it’s ultimately a safety feature. It’s rewarding to think that one day a customer will be able to drive more safely because of a feature I’ve tuned.”

Leveraging a local R&D system in the United States to become a global top-tier brand

Hyundai/Kia has established a localized research and development (R&D) system with the completion of the Mojave Proving Ground. By having the ability to conduct various tests optimized for U.S. terrain, Hyundai Motor Group has completed a local system from product planning to design, design, and testing. This shortened the development period and enabled Hyundai Motor’s Alabama and Kia’s Georgia plants to produce new cars in a timely manner and give them the competitiveness to respond quickly to market conditions. 

A view of Hyundai’s Alabama plant

Matthew R. Seare, Manager of Operations of the Hyundai America Technical Center, expressed his pride in the Mojave Proving Ground through the following. “I’m always proud that I’ve been able to experience firsthand all that Hyundai and Kia have accomplished over the past 20 years, and I find it very rewarding to work with our research engineers who develop the cars. They really love cars and are passionate about making even the smallest changes to them, and it’s here at the Mojave Proving Ground that I get to work with people who have a lot of love and pride in their work.”

Hyundai is proving to be the best on the WRC stage

Hyundai/Kia’s localized R&D system in the United States, including the Mojave Proving Ground, has led to synergies through close exchanges with Namyang R&D Center, a comprehensive R&D control tower in Korea. The Group’s efforts to build great cars continue in many other areas, including the Nürburgring test center in Germany and the establishment of Hyundai Motorsport GmbH. 

The Kia EV9 was named Best SUV at the North American Car of the Year Awards

These efforts are paying off with strong growth in the U.S. market. Hyundai/Kia has enjoyed a new car sales share in the United States of around 10% in the 2020s, with Genesis breaking the record for best-selling car in the United States for the second consecutive year. Growth in global markets is also noteworthy. Hyundai/Kia ranked third in global sales in 2022, 12 years after its last global top-five finish in 2010. It is certain that it will retain its third place in 2023. 

Hyundai Motor Group’s commitment to building better cars has led to several years of winning North American Car of the Year awards

Hyundai and Kia’s dominance of the industry is evidenced by their awards. The dedicated E-GMP electric models, including the IONIQ 5, EV6, GV60, IONIQ 6, and EV9, have been recognized by leading media outlets around the world, winning World Car of the Year (WCOTY), North American Car of the Year (NACOTY), and European Car of the Year (ECOTY).

There are no shortcuts to making better cars. All you can do is constantly test and improve with everything you have at your disposal. Every research engineers at Hyundai Motor Group is well aware of this. Today at the Mojave Proving Ground, the sweat of our research engineers fuels the efforts made for customers.

HMG Journal Operation Team


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