Advanced testing systems supplier AB Dynamics has introduced a major upgrade to its SPMM 5000 K&C testing machines.
K&C Inspect enables users to capture the movement of up to 50 target points in three dimensions; this data is then automatically synchronized and recorded with the traditional data collected during K&C testing. This step forward enables the analysis of a competitor’s vehicle or the validating of the characteristics of a pre-production prototype using an SPMM.
“This is a major breakthrough for K&C testing because it enables our customers to measure the movement of elements of the vehicle that are often unaccounted for in traditional testing,” explained Matthew Dustan, senior project engineer for the SPMM.
“In the past, measurement was more or less limited to wheel position movements and tire contact wheel forces. Body movement was measured by draw wire encoder or inferred from the position of the center table to which the body is clamped. In reality, all vehicles are flexible so by capturing the positions of key points, our clients can derive substantially more information from K&C testing.”
The system uses a pair of Aicon HF4 photometric cameras on an adjustable mounting system with a data capture rate of up to 1,000Hz. A combination of the SPMM and Aicon software locates and tracks the X, Y and Z position of the user-selected targets, automatically transforming the data into K&C rig coordinates.
The displacement data is stored alongside other K&C results in the SPMM database, ready for export and processing, and can be graphed against other test data channels in AB Dynamics’ graphing and analysis programs, including Grapher.
Previous attempts to incorporate accurate deflection measurement into K&C testing using standalone 3D measurement systems have left engineers struggling to reliably orient the camera coordinate system to their other data, thereby failing to get the results in a useable form. K&C Inspect can do this seamlessly, thanks to extensive work by AB Dynamics to effectively integrate the Aicon software with the existing SPMM software.
One of the particular challenges overcome by AB Dynamics in developing the new system was ensuring that the cameras reliably tracked the individual targets at all times. A sophisticated series of logical steps within the software enables the system to identify and track each of the targets and quickly diagnose error conditions, such as a target becoming obscured during suspension movement.
As SPMM users continually look for greater value from K&C testing, adding the capability to accurately measure other deflections is a natural and complementary step. System accuracy varies with the distance from camera to target, being typically 20 microns (in X and Y) and 80 microns (in Z), at 1.5m. The high accuracy of the system enables the measurement of components and body parts that do not deflect greatly during a K&C test, such as subframes.
“In addition to body movements, there are elements of the vehicle suspension and steering systems that move, flex and twist, in ways that our customers are interested in measuring,” said Dustan.
“The K&C Inspect system gives engineers the flexibility to place reflective targets anywhere on the vehicle, within reason, and capture the movements and displacements of the components they are interested in.”
K&C Inspect is aimed at users of both the current SPMM 5000 and the earlier SPMM 4000, provided it has been upgraded to AB Dynamics’ current control system – PowerPMAC.
