To clear a full intensity of a 2017 Acura NSX’s Sport Hybrid SH-AWD powertrain and perform a high targets set for a sum energetic performance, a engineering group took a confidant and serious new direction: a totally clean-sheet, multi-material proceed that breaks new belligerent in a automotive realm—with new materials, new construction methods and new meditative in supercar physique design.
By starting from scratch, a NSX growth group was means to select a optimal member focus and construction methodology for any area of a body, targeting both low mass and ultimate acerbity while also gratifying other vicious pattern objectives such as higher external visibility, world-class pile-up reserve opening and world-class peculiarity and continuance fitting a next-generation Acura supercar.
The finish outcome is a NSX multi-material body, with a aluminum finish space frame, designed to grasp constructional acerbity distant higher to a top-in-class competitors. This high spin of energetic acerbity provides a essential substructure for a NSX’s immediate responses. As a result, drivers will feel their inputs directly translated to a car’s actions with implausible speed and fidelity, while concurrently permitting a limit intensity of a Sport Hybrid SH-AWD complement to be satisfied by a car and driver—the hint of a New Sports eXperience.
“The plea for a physique pattern group was to emanate a physique with a high spin of acerbity to be means to broadcast a full feeling of this powertrain directly to a motorist but delay,” pronounced Shawn Tarr, arch operative for a NSX physique development. “While a all aluminum unibody of a strange NSX was brazen of a time, we would need to demeanour to world-first record in sequence to grasp this new spin of rigidity.”
The NSX physique construction—performed wholly in-house during Acura’s Performance Manufacturing Center (PMC) regulating domestic and globally-sourced parts—is undertaken with innovative new techniques and technologies, and with a fasten to peculiarity unmatched in a supercar realm. As one vicious example, MIG welding of a aluminum-intensive space support is achieved wholly by high-precision robots, with all welds and physique components undergoing a minute investigation by rarely learned PMC coupling technicians.
Building peculiarity and correctness into a space support eliminates a post-construction machining activity that is common in low-volume car manufacturing, including many competing vehicles. This same fasten to next-generation peculiarity by a ideal mix of appurtenance pointing and tellurian craftsmanship can be found in any aspect of NSX’s physique construction, finishing/painting and assembly, and is straightforwardly identifiable in a final product.
Key Body/Frame Features
- Multi-material aluminum-intensive space frame
- Complex high-performance ablation expel aluminum nodes for front vanquish territory (world’s initial automotive application)
- Three dimensionally focussed and quenched ultra-high strength steel A-pillar structure (world’s initial application)
- Carbon fiber core front building panel
- Aluminum and low-density SMC outdoor panels
- Innovative construction techniques including high-accuracy robotic MIG
welding regulating rotating trunnion (rotisserie-type) coupling fixtures (world’s initial automotive application)
- Additional modernized fasten technologies including flow-drill screws and self-piercing rivets
- Environmentally-conscious zirconium space support pre-treatment (Acura first)
Multi-Material Space Frame
The NSX multi-material physique with aluminum-intensive space support offering a growth group a best constructional acerbity and lowest height weight along with higher wrapping for a appetite unit. NVH is also severely minimized by a NSX’s endless tellurian acerbity benchmarks—two times immobile and 3 times energetic levels of torsional acerbity demonstrated by a subsequent top competing car evaluated by a NSX growth team.
Highly firm and reinforced extruded aluminum beams contain a infancy of a space support and are employed for a front and behind support rails and cranky members, front and behind bulkhead support members, building cranky members and side rails. To offer support sound attenuation, a array of these aluminum extrusions are filled with acoustic mist foam, that is used in 38 opposite locations.
Cast aluminum nodes offer as fasten points for a extruded aluminum support members and as ultra-rigid ascent points for a vehicle’s front and behind cessation systems, as good as a behind appetite unit. These nodes are possibly sobriety die expel or, in front and behind vanquish zones, made regulating modernized new ablation casting technology, a world’s initial automotive focus (see next for additional detail).
In another world’s first, a top apportionment of a A-pillars and roof rails, that contain one continual section, are made regulating 3 dimensionally focussed and quenched ultra-high strength steel tubing. This new steel combining routine allows extended styling and external prominence while providing for high roof-crush strength (see next for additional detail).
Aluminum stampings are employed as lightweight closure panels for a behind floor, behind bulkhead and B-pillars. The front building panels are assembled of CO fiber for strength and low weight.
Ablation Cast Nodes
One of a many formidable pattern hurdles in a growth of a all-new Acura NSX was to minimize a front and behind overhangs of a car while handling collision appetite fullness in pivotal areas for pile-up reserve opening and maintaining optimal constructional rigidity. To solve these formidable and competing pattern imperatives, Acura engineers grown innovative new record called ablation casting, an all-new member focus and a world’s-first focus in a car industry. Ablation casting was grown from a elemental investigate thesis to prolongation car focus within a growth cycle of a new NSX—a vital design, engineering and prolongation achievement.
Ablation expel aluminum nodes within a NSX space support shown in yellow.
Ablation casting is employed in a origination of 6 fasten members, or nodes—two top and dual reduce nodes in a front frame, and dual nodes in a behind frame. These nodes also offer as ultra-rigid ascent points for both a front and behind suspensions. The front top nodes are designed to catch and rubbish appetite in a frontal collision. The dual ablation expel nodes during a behind of a car are designed for high strength to lessen brazen transformation of a appetite territory in a eventuality of a serious behind collision.
Ablation casting involves a fast cooling of a sand-cast aluminum member around a accurate focus of H2O jets, that ablate a silt mold while cooling a part. This routine allows for a fine-tuning of both a expel part’s figure and a member properties while minimizing weight with vale forms and optimized wall thicknesses. Unlike normal castings, a high-strength and plastic properties of a ablation expel members concede these sections of a space support to gradually vanquish during 155 kN of load; and a behind support nodes are designed to withstand adult to 210 kN of load.
The ablation expel nodes are assembled in-house during a company’s Anna, Ohio engine plant, that has endless knowledge with pointing casting. The Anna Engine Plant is a usually automotive prolongation trickery in a universe utilizing ablation casting technology.
3-Dimensional Bent and Quenched Ultra-High Strength A-Pillar
The strange NSX was famous for a superb brazen visibility, giving drivers a feeling of being connected to a highway while optimizing visibility, and this pattern charge was deliberate essential to preserving a core evil of a NSX pushing experience. For a next-generation NSX A-pillars, new advancements in combining ultra-high strength steel collection supposing a ideal solution, assembly a engineering team’s goals for reserve opening while maximizing brazen visibility.
The NSX’s A-pillars have been precisely crafted regulating an all-new, three-dimensional combining and tempering routine that allows for a formidable partial figure with ultra-high tensile strength. This “3D focussed and quenched” member is exhilarated and afterwards made in 3 measure by an articulating robotic arm, after that a partial is quenched regulating H2O jets to grasp an ultra-high tensile strength of 1,500 megapascals. This routine enables a really skinny cross-section with accurate figure selection and tolerances, while also assembly a increasing constructional acerbity standards for roof-crush performance. Utilization of this routine reduced a breadth of a A-Pillar—at only 3.5 inches (89 millimeters) in width—by one in. (25 mm) compared to a compulsory construction process; a perspective is a full 36 percent reduction blocked than a next-best supercar evaluated by a Acura group and even improved than a strange NSX.
To forestall galvanic corrosion, a member receives an electro-deposited cloaking before being assimilated to a hammered steel structure during a bottom of a A-pillars.
Carbon Fiber Floor
When evaluating member combination and chain via a body, a pattern group dynamic that CO fiber would offer as a ideal member for a motorist and newcomer building section. In further to a light weight, a member is clever adequate to hoop a loads occupants place on a building during car ingress/egress. Aluminum sheeting would have compulsory additional cross-member support support underneath it that would have in spin combined additional weight.
Space Frame Construction
A array of modernized technologies and techniques are used in a construction of a NSX space frame, that is conducted wholly in-house during a company’s new Performance Manufacturing Center in Marysville, Ohio. The NSX growth and prolongation teams were dynamic to say in-house control of a finish physique construction routine to safeguard a top levels of peculiarity and opening for Acura customers.
Through a doing of despotic manufacturing/build processes and peculiarity controls, a dimensional correctness of a multi-material physique is reliable via a construction process, expelling a need for post-process machining. This is a singular prolongation complement and a good indicate of honour for Acura, permitting a group to grasp peculiarity and correctness levels higher to a competitors.
Metal Inert GAS (MIG) Welding
Metal Inert Gas (MIG) welding is employed for a infancy of a aluminum space support construction. The support contains some-more than 860 MIG coupling points, where some-more than 112 feet (34 meters) of MIG handle is applied. Most welding is finished by entirely programmed robotic coupling arms that offer well-developed pointing and control.
For a underbody territory of a space frame, construction is finished in a array of 4 stations, where rarely learned coupling technicians work in tandem with programmed robotic coupling machines to safeguard a top peculiarity parts. Specialized design frame-style fixtures, grown in-house, are used to reason a member pieces, permitting for accurate control of a coupling routine and dimensional correctness of a part. Four of these fixtures are means to stagger 360-degrees to urge a entrance of robotic coupling arms to a partial and to concede for full datum referencing (highly accurate measurements between lines on a three-dimensional X, Y and Z axis) of a part.
Strategic sequencing of a countless coupling processes mitigates a intensity for collection deformation from feverishness buildup, a common plea in a welding of aluminum components. The peculiarity of welds and dimensional correctness of a partial are reliable during any hire by technicians by visible inspection.
The building and top components of a space support are afterwards assimilated by large, entirely robotic ubiquitous welders, that also exercise rotating trunion-type fixtures with 360-degree movement. Twin robotic coupling arms are means to control welding processes concurrently to support in both prolongation potency and in a uniform placement of heat, mitigating a intensity for partial deformation.
Additional physique fasten technologies including self-piercing rivets, flow-drill screws, and drum hemming, any selected for a specific and singular qualities within a given member of a altogether space support construction.
Self-piercing rivets (SPR) concede for a fasten of dual or some-more layers of member but carrying to pre-drill or punch a hole and are ideal for fasten piece materials while providing an unusually watertight joint. The NSX space support contains some-more than 345 self-piercing rivets.
Flow-drill screws (FDS) are used in a place of a nut-and-bolt focus in countless areas of a space frame, shortening both weight and collection complexity. FDS are also quite good matched to areas of a physique where one side of a partial is untouched by compulsory tools, such as in an extruded component. More than 245 flow-drill screws are practical to a NSX space frame.
Roller Hemming joins dual pieces of piece steel by formulating a sharp-angle bend, permitting a steel to be folded behind over itself, formulating a clever and parsimonious corner with a purify and finished edge. There is scarcely 60 feet (18 meters) of drum hemming corner on a NSX space frame.
Space Frame Advanced Conversion Coating
Prior to final assembly—where a space support is propitious with a suspension, powertrain, electrical, interior and other componentry—the entirely assembled space support undergoes an modernized acclimatisation cloaking routine regulating a zirconium pre-treatment member and an e-coat routine as an additional separator to galvanic gnawing while progressing a low environmental impact.
The use of zirconium, an Acura and Honda association first, eliminates some-more than 90 percent of a rubbish byproduct that formula from a use of some-more compulsory zinc-phosphate material. This byproduct, that contains complicated metals, contingency be likely of in landfills, formulating a poignant rubbish stream. The use of a zirconium acclimatisation cloaking is partial of a bid to emanate a prolongation routine with a low environmental impact, unchanging with a ideal of a next-generation hybrid supercar.
Body Repair and Serviceability
To support in a palliate and cost of collision repair, as good as to strengthen to a high grade a dimensional correctness and firmness of a NSX space support during a collision repair, a NSX growth group worked closely with Acura use engineering group members to exercise an altogether modular construction concept: Space support components can be purchased and transposed away or as pre-assembled modular deputy sections. For example, there are “light-collision” and “medium-collision” deputy sections for both a front and behind sections of a vehicle, that are designed to minimize a volume of welding activity required.
For endless servicing of a powertrain (engine, behind engine and transaxle), a group designed a modular behind middle physique section—once a behind fascia row is removed, a whole case territory of a car can be private as a singular territory to assent easy and unlimited entrance to a mid-mounted V-6 engine. The case structure also helps locate outdoor physique panels.