Tech Briefs
Mitsubishi Electric builds all-weather dyno chamber
 A robotic driver simulates the movements of a driver, providing reliability from test to test. |
As a means of spurring new engine-management-system business, Mitsubishi Electric Automotive America, Inc.'s recently occupied research and design facility features a 9000-ft2 (836-m2), all-weather chassis dynamometer test chamber.
"It's a popular trend for manufacturing companies to outsource (testing), but our decision to have our own chassis dynamometer room is identical to why we make our own manufacturing equipment," said Michael DeLano, Senior Vice President of Powertrain, Body, and Chassis for Mitsubishi Electric in Northville, MI. "If we make a better mousetrap, we don't want anyone to duplicate it."
The chassis dynamometer chamber is sized to test a vehicle with 400 engine hp (300 kW) or 350 hp (260 kW) at the wheels. Test room temperature can be heated to 122°F (50°C) and chilled to -40°F (-40°C), while humidity can span 0 to 90%. The enclosed environment's frontal wind speed can be set between 0 and 75 mph (120 km/h). Sunlight radiation/intensity is duplicated via 300 infrared filament bulbs that each produce 400 W. The entire grid can produce 1400 W/m2.
 The dynamometer control room houses all the controls for weather conditions and test analysis. |
An adjoining control room uses six dedicated computer systems. In addition to the environmental controls, the dynamometer's computer adjusts engine load by simulating driving conditions such as uphill or downhill on front-wheel-drive or rear-wheel-drive axles. (When converted, the dynamometer can handle all-wheel-drive or four-wheel-drive vehicles.) Drive test patterns—matching Environmental Protection Agency guidelines—are set by another computer.
The control room also includes an emissions-testing analyzer system and an engine controller interface that uses Mitsubishi Electric-written software to tweak or tailor all engine calibration parameters. A driver control panel that is linked to an in-vehicle robot's mechanical legs and arm provides consistent and repeatable power to the brake pedal, accelerator pedal, gear shifts, and, when equipped with a manual transmission, the clutch.
Components such as starters, alternators, coils, and valves are tested elsewhere within the 18,000-ft2 (1670-m2) building. Adjacent to the research and development center is a new 100,000-ft2 (9290-m2) facility for sales, distribution, production control, quality control, application engineering, and audio/entertainment products testing labs. Mitsubishi Electric provides engineering, manufacturing, sales/marketing, and distribution of electrical and electronic systems and components for automakers and industrial engine manufacturers.
- Kami Buchholz
Power promoting from GM
 This 3.6-L V6 is the first in a family of DOHC engines from General Motors that will have a displacement range capable of 2.8 to 3.8 L. Engines in this group will feature four valves per cylinder, roller-finger followers, and electronic throttle control. |
V6 engines are among highlights of the next-generation powertrain portfolio from General Motors Corp. The first overhead valve (OHV) engine variant in the V6 family, a 3.5-L, will debut in the 2004 Chevrolet Malibu.
"This engine will have the first application of electronic throttle control on a transverse front-wheel-drive V6 engine," Dick Michalski, Chief Engineer for the 3.5-L Overhead Valve V6 at GM Powertrain, said during an advanced technology event at GM's proving ground in Milford, MI.
The GM V6 OHV engine family—with displacements up to 3.9 L—features sequential port fuel injection, large-pin steel crankshaft, polymer-coated pistons, powder metal connecting rods, graphite head gaskets, and piston oil squirters. "Cylinders five and six run the hottest because of how the water runs through the engine, and we wanted to cool those cylinders for durability reasons," said Michalski, referencing the piston oil squirters on the 3.5-L OHV engine.
A new global dual overhead camshaft (DOHC) V6 engine family will use piston-cooling oil jets on all six cylinders. The first member of the DOHC V6 engine group will be a 3.6-L producing approximately 255 hp (190 kW) and 250 lb•ft (340 N•m).
The 3.5-L OHV engine, with preliminary numbers of 190 hp (140 kW) at 5600 rpm and 220 lb•ft (300 N•m) at 4000 rpm, will have equal length cast-aluminum intake runners and laminated exhaust manifold shields as a means of addressing noise quality. Key materials used on the new V6 include cast-iron cylinder block, semi-permanent mold 319-aluminum cylinder heads, as well as sand-cast 319-aluminum upper and lower intake manifold.
GM will introduce its fuel-saving Displacement on Demand cylinder deactivation technology on the OHV V6 family in the 2005 calendar year and on V8 engines in 2004. "The Generation-Four V8 will have a different engine controller—a faster processor, more memory—to drive our Displacement on Demand feature," said John Juriga, Assistant Chief Engineer for Small Block V8 Engines at GM Powertrain.
An all-new V12 will power Cadillac vehicles in future model years. Providing more than 500 hp (370 kW), the direct-injection gasoline 7.5-L concept engine uses a flywheel alternator-starter as well as cam drives on the engine backside. "We put a lot of the technologies on it just to experiment," said Ned McClurg, Vice President of Engineering for GM Powertrain. "It's a concept engine, (so) it's not the way it will go to production. There will be some changes."
Beginning in the 2005 calendar year, GM adds a Hydra-Matic automatic transmission to the portfolio. "This will be our first production six-speed automatic transmission for GM," said Dennis Provenzano, Program Manager for the six-speed transmission family. Four transmission variants are planned with three of the units designed to handle passenger car and truck duty cycles.
The new transmission provides enhanced performance algorithm shift, clutch-to-clutch shifting, automatic grade braking, tap up/down operation (Driver Shift Control), an integrated center differential for full-time all-wheel capability, and an internal control module using micro-hybrid technology. "By having an internal transmission controller, you're able to reduce the number of wire connections within the transmission and external to the transmission by approximately 50%," said Veronica Mirabitur-Spitza, Chief Engineer for the six-speed transmission family.
"The majority—70 to 80%—of the North American portfolio for GM will be high-value powertrains," said Thomas Stephens, GM Powertrain Group Vice President, noting that high-value powertrains offer performance, fuel economy, and low-level noise and vibration benefits at an affordable cost.
- Kami Buchholz
