Tuning is the vital process undertaken before a fatigue test to allow the system to properly control the machine, and for your test to run successfully.

It traditionally involves loading the test specimen with a number of sudden step changes and automatically or manually iterating the control gains until the performance meets the test requirements. This process is time consuming and daunting for less experienced users.

Fatigue systems are high performance machines that can run in load or strain control at high frequencies.

Unlike a traditional position controlled electromechanical system, this requires sophisticated control techniques to provide smooth and controlled motion. Ultimately, this means the system needs to be tuned before each new test so that the performance and control is optimized for that specimen material and geometry, so your data is accurate and repeatable. Failure to tune can result in system instability and unreliable data.

Stiffness Based Tuning is available on ElectroPuls® systems, where it was originally launched in 2006, as well as on Instron's servohydraulic and electrodynamic testing systems powered by the 8800MT controller.

In many cases, yes. Systems running on the 8800MT controller can take advantage of Stiffness Based Tuning as part of a controller upgrade. Contact an Instron representative to determine whether your existing system is eligible.

Stiffness Based Tuning is designed to optimize performance across a wide range of specimen materials, geometries, and control modes, with tuning algorithms continuously developed and refined to support new applications as they arise.

Manual tuning traditionally requires loading the specimen with a series of step changes and iterating control gains by hand until performance meets test requirements — a process that's time-consuming and can be daunting for less experienced users. Stiffness Based Tuning automates this process, delivering over 75% time savings while removing the need for pre-cycling the specimen.

Stiffness Based Tuning is built into the control software of supported systems, so no separate purchase or license is required beyond the system configuration itself.

Stiffness Based Tuning is designed to improve — not compromise — the accuracy and repeatability of your test data, supporting compliance with the same testing standards your system already meets.