What does the youth market want in an automobile? Many companies at the recent SEMA (Specialty Equipment Market Association) Show in Las Vegas attempted to answer that question with their product lines. A team of students in the master's program in automotive engineering at Clemson University's International Center for Automotive Research (CU-ICAR) submitted its own proposal. Named the "Next-BIG-Thing" (NBT), it was viewed as a practical approach that could be marketed at a price of about $28,000.
The team, led by Dr. Paul J. Venhovens, who holds the BMW-endowed chair in systems integration at CU-ICAR, said it liked "cool" cars, but that's a term heard often at the SEMA Show. The students studied Gen Y buyer satisfaction data from AutoPacific to develop insights. They enlisted many sponsors, led by Mazda North American Operation. It supplied a Mazda2, RX-8, and MX-5 Miata (plus various components) and asked only that the concept capture the Mazda essence and evoke emotions similar to the first Miata (introduced in 1988). The Mazda Foundation also contributed, funding three fellowships.
The CU-ICAR six-passenger concept is physically far away from the two-seat Miata, but times and the current generation of new buyers are different too. It's an era of downsized, turbocharged engines.
The front-drive powertrain is a Mazda-supplied 1.5-L four-cylinder with a Honeywell Garrett GT2052 turbocharger, bolted to a five-speed Mazda manual transmission. The naturally aspirated version of the 1.5-L unit, as used in the Mazda2, produces 100 hp (76 kW), 98 lb·ft (132 N·m). The NBT version is rated at 140 hp (105 kW) and 155 lb·ft (210 N·m).
The NBT has a second electric powertrain in the rear. This not only permits all-wheel-drive if needed in northern climes, but because of the parallel operation, the NBT can be expected to deliver both fuel efficiency and solid performance, in line with Mazda's Zoom-Zoom brand image.
The combined peak power is 208 (155 kW); combined peak torque is 262 lb·ft (335 N·m). The NBT team said estimated road-test numbers are 42 mpg city/49 mpg highway, 0-60 mph (0-97 km/h) in 7.5 s, and a top speed of 125 mph (200 km/h).
The rear electric drive, supplied by TM4 Electrodynamic Systems, uses a three-phase permanent magnet brushless AC motor with a peak output of 80 kW, peak torque of 125 lb·ft (170 N·m), and continuous output of 37 kW. The motor, wired through an inverter/controller, is fed by a lithium polymer battery pack from Energy Innovation Group with 108 3.2-V cells in three modules with a capacity of 2.4 kW·h. The electric drive configuration, which runs through a single-speed GKN single-speed electric transmission with a 9.59:1 gear ratio, not only provides power assist but also is capable of regenerative braking and brief operation in all-electric mode.
NBT's six-passenger capacity in two seating rows doesn't make it a substitute for a minivan or crossover. The idea is to provide seating for a group of Gen Y friends who want to travel together in one vehicle, reflecting the generation's social and environmental values. The interior is sized to hold four 95th percentile males in the four side seats, and two 50th percentile people in the middle seats. There's a 12-in touchscreen infotainment center in the center stack.
The suspension is double-wishbone in front, multilink in the rear, adapted from the RX-8, but with Eibach Pro-System Plus springs and shock absorbers. An electrichydraulic power steering and vented disc brakes front and rear also were adapted from the Mazda "parts bin," as (without a full load) the NBT is intended to have Mazda-like sporty driving characteristics. NBT will ride on Michelin Pilot Super Sport 225/40ZR19 XL93 tires mounted on 19-in wheels from Enkei, aftermarket producer of lightweight wheels.
Total mass of the prototype is just 2755 lb (1250 kg), although a vehicle with the body panels and interior trim added is projected to end up at 3086 lb (1400 kg). A production car with optimized metal thicknesses might weigh less, Dr. Venhovens said. With a driver and single front passenger, front/rear weight distribution is 50/50. Overall length is 175.2 in (4450 mm) on a wheelbase of 107.5 in (2730 mm). Cargo volume is just 10.6 ft³ (300 L), so the six Gen Y friends would have to "travel light."
Industrial Origami technology
The concept body-in-white, an aluminum unit body with a mass of just 463 lb (210 kg), was made from thin sheets of metal folded in unique patterns and joined with structural adhesives, based on the folded metal technology of Industrial Origami, a support partner for the CU-ICAR project. The folding metal approach enabled complex, high-load-bearing structures to be made with simple fixtures in the university's laboratories, rather than with large, expensive equipment such as dies and stamping equipment, an advantageous characteristic for the student project.
Tight time frame
Nominally a two-year project, the NBT development began in earnest in the spring of 2011, with a team of 54 students that evaluated concepts that would tie in to the Mazda brand message. A CU-ICAR group of 28 engineering students started virtual project development in September 2011, while 15 transportation design students at the Art Center College of Design of Pasadena, CA, began the exterior design process.
In January 2012, a team of 13 automotive engineering students started a six-month full-time program to develop the design integration, packaging, functional analyses, and the steps needed for vehicle prototyping. First parts for the body-in-white arrived in July, and the origami metal folding began and was completed by the end of August. At that point, the integration of the chassis and powertrain began. "There is no book for this integration," Dr. Venhovens said, explaining it was a learning by testing and doing process.
The exterior design chosen was developed by Fred Naaman, and a 1:3 scale model was displayed at the SEMA show. A decision on body panels is expected soon, with sustainable materials desirable if feasible. Dr. Venhovens hopes to show a completed project at the 2014 North American International Auto Show in Detroit. In theory, the concept could meet a 2015 start-of-production date.