What's under the skin.
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What's under the skin.
As an engineer in the Aerospace industry, I wanted to know what makes the new RDX special. There is nothing I hate more than squeaks, rattles, buzzing etc. I would like to share what i have found with the forum. I drove an Advance FWD and I can say it is rock solid.
Rigid and Lightweight New Body Structure
The new RDX body structure provides the foundations for its exception ride and handling capabilities, quiet cabin and top-class collision safety performance. The new body was designed from the ground up to be lighter, more rigid and tightly sealed and incorporates numerous new engineering features, including:
• A double-ring rear body/frame structure for dramatically improved rear body rigidity in a five-door SUV design (an Acura first)
• A two-piece ultra-high strength steel front door ring design for reduced weight and improved collision safety performance (a world’s first)
• The application of sound-absorbing acoustic spray foam to 12 body cavities, which combine with triple sealed doors and other sound-deadening measures to deliver exceptional cabin quietness (an RDX first)
• The use of high-performance structural adhesives in the body construction to reduce weight and improve rigidity (an Acura first)
Despite being 41 pounds lighter than the previous-generation unibody, global rigidity of the new 2019 RDX body structure is up 38.3 percent which supports improved fine-tuning of the suspension systems for superior ride and handling performance. The stiff body structure allows the chassis to work more effectively and reduces the suspension action needed to control body motion. Another benefit of the rigid body structure is a quieter and more comfortable ride for passengers, with less noise, vibration and harshness (NVH) felt over a wide range of driving conditions.
Advanced Compatibility Engineering™ (ACE™) Body Structure
The new RDX's Advanced Compatibility Engineering (ACE) body structure is an exclusive body design that enhances occupant protection and crash compatibility in frontal collisions. It uses a network of connected structural elements to distribute crash energy more evenly throughout the front of the vehicle, helping to reduce the forces transferred to the passenger compartment. ACE channels frontal crash energy to both upper and lower structural elements, including the floor frame rails, side sills and A-pillars. It can help to more evenly disperse the forces transferred to other vehicles in a crash as well. ACE also helps reduce the chances that one vehicle will override another, improving crash compatibility of vehicles that differ in size. ACE goes further by offering additional strength and protection in small overlap frontal collisions, which are among the most severe. (See the Safety and Driver Assistance section for more information.)
Crash Stroke
The RDX’s ACE™ body structure features crash stroke technology. In a frontal collision, the lower section of the front vehicle frame hinges in a manner that helps direct the engine down and rearward to minimize cabin intrusion.
Ultra-High Strength Door Rings
The new 2019 RDX features ultra-high-strength steel door reinforcement beams and a new world’s first technology – two-piece (inner and outer) ultra-high-strength front door stiffener rings made of 1500-MPa hot-stamped steel. Laser welded and significantly stronger than conventional steel, the ultra-high-strength steel reinforcements are designed to help better protect occupants in a frontal or side impact. Their increased strength allows component weight to be reduced 28 pounds compared to the previous design, which also helps reduce overall vehicle mass for improved handling and fuel efficiency.
Double Ring Rear Frame Structure
The rear portion of the RDX’s unibody features a new “double ring” structural design that incorporates two interconnected metal structures into the unibody: One utilizing the C-pillars, rear wheel arches and floor area; and the other utilizing a unique pillar structure above the rear suspension dampers, roof and floor area. This sophisticated design substantially improves torsional rigidity in a five-door “two-box” SUV body structure that includes a standard panoramic moonroof, while also creating multiple load paths for forces introduced through the rear suspension, resulting in significantly improved ride and handling.
Roll-Hemmed Roof Structure
The application of a panoramic moonroof to all 2019 RDX grades required an all-new roof design and engineering in order to retain the necessary stiffness and safety performance. A key part of this new design is a roll-hemmed roof structure. A first for Acura, the roll-hemmed roof structure stiffens the exterior roof panel, enabling the large panoramic moonroof to be added without sacrificing roof strength or overall unibody stiffness.
High-Performance Structural Adhesive
The 2019 RDX makes widespread use of structural adhesives throughout the unibody, supplementing its structural welds and significantly increasing rigidity without the increased mass of additional steel components. The high-performance adhesive material is used along the roof edges, in the roof pillars, side sills and rear wheelhouse, and extensively in the vehicle’s floor pan.
Applied before the body panels are welded together, some 112 feet of structural adhesive directly contribute 6 percent to RDX’s improvement body rigidity – including gains in torsional, bending and lateral stiffness. It helps reduce the new RDX’s unibody weight by 19.8 pounds compared to the previous generation.
Body Rigidity
The new RDX likewise substantially outperforms the previous generation in torsional, bending and lateral rigidity. Global body rigidity is increased 38.3 percent, directly benefiting the RDX’s handling response and precision.
Fitting Point Stiffness
The RDX has eight fitting points where suspension components attach to the unibody – two for the MacPherson strut front suspension and six for the multi-link rear suspension. In all cases, the new RDX outperforms the previous generation unibody by a significant margin, with an average increase of 52.5 percent. Dividends include improved steering precision, road holding and ride quality, and reduced road noise imparted to the cabin.
Fitting Point Location Improvement vs. 2018 RDX
Front Damper Mounts +46%
C-Pillar Mounts +61%
D-Pillar Mounts +77%
Rear Damper Mounts +26%
Noise, Vibration and Harshness (NVH) Countermeasures
Extensive noise, vibration and harshness (NVH) countermeasures incorporated into the RDX include strategically placed body sealants, structural adhesives and other measures to reduce vibration and the transmission of noise.
Wind and Exterior Ambient Noise Reduction
• Dual 360-degree molded door seals reduce wind noise and improve isolation.
• Door gap seals at all door edges further keep wind noise from entering the cabin.
Acoustic Spray Foam
New to the RDX, the application of acoustic spray foam provides extra sound insulation by blocking off hollow pillars, which reduces the transmission of wind and road noise into the passenger cabin by 2 decibels. The foam, applied to six locations on each side of the RDX (12 total) is heated and injected into:
• The base of the A-, B-, C- and D-pillars
• The base of the windshield frame
• The unique pillar structure above the rear damper
Sound Deadening and Noise Isolation
The new RDX has widespread application of sound deadening material and other insulation throughout the unibody to reduce both engine and road noise. Special spray-in sound-deadening material is located in key floor areas of the cabin, and additional insulation is positioned at the firewall and in the rear corners of the unibody. Altogether, the 2019 RDX has 15 percent more insulation coverage than the previous RDX generation, further helping to isolate the cabin from external noise, vibration and harshness (NVH); Advance package includes additional sound deadening for an even quieter driving experience.
Aluminum Components
Aluminum stampings used in key locations help mitigate weight increases and provide benefits to handling, fuel efficiency and emissions.
Rigid and Lightweight New Body Structure
The new RDX body structure provides the foundations for its exception ride and handling capabilities, quiet cabin and top-class collision safety performance. The new body was designed from the ground up to be lighter, more rigid and tightly sealed and incorporates numerous new engineering features, including:
• A double-ring rear body/frame structure for dramatically improved rear body rigidity in a five-door SUV design (an Acura first)
• A two-piece ultra-high strength steel front door ring design for reduced weight and improved collision safety performance (a world’s first)
• The application of sound-absorbing acoustic spray foam to 12 body cavities, which combine with triple sealed doors and other sound-deadening measures to deliver exceptional cabin quietness (an RDX first)
• The use of high-performance structural adhesives in the body construction to reduce weight and improve rigidity (an Acura first)
Despite being 41 pounds lighter than the previous-generation unibody, global rigidity of the new 2019 RDX body structure is up 38.3 percent which supports improved fine-tuning of the suspension systems for superior ride and handling performance. The stiff body structure allows the chassis to work more effectively and reduces the suspension action needed to control body motion. Another benefit of the rigid body structure is a quieter and more comfortable ride for passengers, with less noise, vibration and harshness (NVH) felt over a wide range of driving conditions.
Advanced Compatibility Engineering™ (ACE™) Body Structure
The new RDX's Advanced Compatibility Engineering (ACE) body structure is an exclusive body design that enhances occupant protection and crash compatibility in frontal collisions. It uses a network of connected structural elements to distribute crash energy more evenly throughout the front of the vehicle, helping to reduce the forces transferred to the passenger compartment. ACE channels frontal crash energy to both upper and lower structural elements, including the floor frame rails, side sills and A-pillars. It can help to more evenly disperse the forces transferred to other vehicles in a crash as well. ACE also helps reduce the chances that one vehicle will override another, improving crash compatibility of vehicles that differ in size. ACE goes further by offering additional strength and protection in small overlap frontal collisions, which are among the most severe. (See the Safety and Driver Assistance section for more information.)
Crash Stroke
The RDX’s ACE™ body structure features crash stroke technology. In a frontal collision, the lower section of the front vehicle frame hinges in a manner that helps direct the engine down and rearward to minimize cabin intrusion.
Ultra-High Strength Door Rings
The new 2019 RDX features ultra-high-strength steel door reinforcement beams and a new world’s first technology – two-piece (inner and outer) ultra-high-strength front door stiffener rings made of 1500-MPa hot-stamped steel. Laser welded and significantly stronger than conventional steel, the ultra-high-strength steel reinforcements are designed to help better protect occupants in a frontal or side impact. Their increased strength allows component weight to be reduced 28 pounds compared to the previous design, which also helps reduce overall vehicle mass for improved handling and fuel efficiency.
Double Ring Rear Frame Structure
The rear portion of the RDX’s unibody features a new “double ring” structural design that incorporates two interconnected metal structures into the unibody: One utilizing the C-pillars, rear wheel arches and floor area; and the other utilizing a unique pillar structure above the rear suspension dampers, roof and floor area. This sophisticated design substantially improves torsional rigidity in a five-door “two-box” SUV body structure that includes a standard panoramic moonroof, while also creating multiple load paths for forces introduced through the rear suspension, resulting in significantly improved ride and handling.
Roll-Hemmed Roof Structure
The application of a panoramic moonroof to all 2019 RDX grades required an all-new roof design and engineering in order to retain the necessary stiffness and safety performance. A key part of this new design is a roll-hemmed roof structure. A first for Acura, the roll-hemmed roof structure stiffens the exterior roof panel, enabling the large panoramic moonroof to be added without sacrificing roof strength or overall unibody stiffness.
High-Performance Structural Adhesive
The 2019 RDX makes widespread use of structural adhesives throughout the unibody, supplementing its structural welds and significantly increasing rigidity without the increased mass of additional steel components. The high-performance adhesive material is used along the roof edges, in the roof pillars, side sills and rear wheelhouse, and extensively in the vehicle’s floor pan.
Applied before the body panels are welded together, some 112 feet of structural adhesive directly contribute 6 percent to RDX’s improvement body rigidity – including gains in torsional, bending and lateral stiffness. It helps reduce the new RDX’s unibody weight by 19.8 pounds compared to the previous generation.
Body Rigidity
The new RDX likewise substantially outperforms the previous generation in torsional, bending and lateral rigidity. Global body rigidity is increased 38.3 percent, directly benefiting the RDX’s handling response and precision.
Fitting Point Stiffness
The RDX has eight fitting points where suspension components attach to the unibody – two for the MacPherson strut front suspension and six for the multi-link rear suspension. In all cases, the new RDX outperforms the previous generation unibody by a significant margin, with an average increase of 52.5 percent. Dividends include improved steering precision, road holding and ride quality, and reduced road noise imparted to the cabin.
Fitting Point Location Improvement vs. 2018 RDX
Front Damper Mounts +46%
C-Pillar Mounts +61%
D-Pillar Mounts +77%
Rear Damper Mounts +26%
Noise, Vibration and Harshness (NVH) Countermeasures
Extensive noise, vibration and harshness (NVH) countermeasures incorporated into the RDX include strategically placed body sealants, structural adhesives and other measures to reduce vibration and the transmission of noise.
Wind and Exterior Ambient Noise Reduction
• Dual 360-degree molded door seals reduce wind noise and improve isolation.
• Door gap seals at all door edges further keep wind noise from entering the cabin.
Acoustic Spray Foam
New to the RDX, the application of acoustic spray foam provides extra sound insulation by blocking off hollow pillars, which reduces the transmission of wind and road noise into the passenger cabin by 2 decibels. The foam, applied to six locations on each side of the RDX (12 total) is heated and injected into:
• The base of the A-, B-, C- and D-pillars
• The base of the windshield frame
• The unique pillar structure above the rear damper
Sound Deadening and Noise Isolation
The new RDX has widespread application of sound deadening material and other insulation throughout the unibody to reduce both engine and road noise. Special spray-in sound-deadening material is located in key floor areas of the cabin, and additional insulation is positioned at the firewall and in the rear corners of the unibody. Altogether, the 2019 RDX has 15 percent more insulation coverage than the previous RDX generation, further helping to isolate the cabin from external noise, vibration and harshness (NVH); Advance package includes additional sound deadening for an even quieter driving experience.
Aluminum Components
Aluminum stampings used in key locations help mitigate weight increases and provide benefits to handling, fuel efficiency and emissions.
