Sierra Research | Emission Testing Facilities

Instrumented Vehicles − Sierra has designed, configured and operated more than a dozen instrumented vehicles for a variety of private and government clients.

These vehicles were instrumented for on-road second-by-second measurement of exhaust emissions, ambient particles and gases, OBDII status via radio-transponder, and accelerometer-based grade measurement. Sierra owns two instrumented vehicles with GPS locators, grill-mounted laser rangefinder/velocimeters that make it possible to record the speed of chased vehicles, and video capture systems for use as "chase cars". Computers in the vehicles capture the data as well as allowing the operator to record roadway conditions and other customized information such as marking waypoints, identifying target types contemporaneously, etc. On-board portable emissions measurement systems can be used to measure HC, CO, CO2, NO and O2 exhaust concentrations of chased vehicles. Sierra has conducted chase car activities in Los Angeles (multiple times) and other California cities, Spokane, Baltimore, Cincinnati, Fairbanks, and Anchorage.

Chassis Dynamometer Cell − A Clayton DC-100 chassis dynamometer provides both mechanical and electric inertia simulation, allowing for the testing of vehicles ranging from 1,000 to 9,000 lbs loaded weight under a wide variety of conditions, using standard and custom driving cycles. Exhaust emissions measurement is provided by a Horiba constant volume sampler (CVS) and gas analysis system.

A Sierra-designed data acquisition and analyzer control system (with automated range changing) provides modal emissions measurement capability. Modifications to the CVS system eliminate the inaccuracy associated with variable tailpipe-to-analyzer delay that occurs with conventional CVS systems.