Dynamic Research, Inc (DRI) has opened a new kinematics and compliance (K&C) test facility at its California proving ground, located outside Bakersfield. A key part of the facility is an SPMM test machine sourced from DRI’s sister company, AB Dynamics.
The K&C facility has been purpose-built for the testing and development of vehicles and is intended to be used by OEMs, suppliers and motorsport teams to measure and evaluate vehicle suspension systems accurately. DRI says the facility makes it the only independent site in North America to provide the full suite of K&C tests as well as Centre of Gravity (CG) and Moment of Inertia (MoI) measurements.
“Using the AB Dynamics SPMM as a basis, we plan to expand our capabilities to become a virtual one-stop-shop for vehicle dynamics measurement and testing,” said Joe Kelly, chief engineer at DRI. “Coupled with our existing vehicle dynamics area and full-scale test capabilities and instrumentation, the SPMM will enable us to serve our clients with unmatched flexibility and depth of experience across a wide range of vehicle dynamics related topics. Emerging vehicle manufacturers can now have access to the kinds of equipment that were only previously the domain of legacy manufacturers.”
The SPMM utilises a novel moving centre table design that manipulates a vehicle’s body to generate the necessary movement and force to the suspension. This design means the ground plane (road) remains fixed when simulating vehicle cornering and braking to more accurately replicate on-road vehicle behaviour.
This architecture also helps ensure the measurement equipment connected to the vehicle’s wheels remains relatively static. Compared to some K&C systems, the travel being measured is an order of magnitude less and the loads being received to the cells are direct, resulting in accurate measurements.
The table is precisely controlled in six degrees of freedom by electromechanical actuators, which enable a combination of roll, pitch, bounce and yaw motion to be applied to the vehicle body. As a closed-loop system, it requires no iteration to reach the desired drive commands, which reduces testing time.
The SPMM can lift, roll and tilt the test vehicle, enabling the full MoI and CG properties of the vehicle to be derived. Alongside the standard suite of K&C tests, this provides all of the chassis-based data required to create accurate digital vehicle models. The measurement data can be directly exported into CarSim, CarMaker and MathWorks.
The facility offers a full suite of K&C services, including industry standard tests such as bounce, bounce-pitch, roll, longitudinal compliance, lateral compliance, aligning torque and steering. The company can also develop bespoke tests to meet customers’ specific research and development requirements.
Further developments are planned for DRI’s California facility, including the addition of a highly accurate 3D Coordinate Measuring Machine (CMM). This machine calculates the exact coordinates of the pivot points as well as the locations of key components in a vehicle, such as inboard bushings and damper mountings. This data is important when assessing manufacturing tolerances on pre-production vehicles.
The facility will also offer high-resolution video synchronised with the test programme. This will make it quick and easy to play back and review any anomalies in the data to better understand their source.
