As well as controlling the measured sarcomere length of the preparation, SLControl allows the user to perform experiments under tension control. In this mode, the system continually adjusts the motor position so that the muscle tension tracks a pre-defined tension waveform. In the example shown here, the muscle tension is first ramped upwards and then suddenly released to the pre-ramp level. Measuring the resulting length change (both overall muscle length and sarcomere length) allows the user to investigate the mechanical properties of the preparation.
SLControl supports a number of different tension control experiment modes. Perhaps the most important of these for most users is the isotonic release, in which the muscle is first held isometrically, and then released to shorten against a fixed load. Varying the release load, allows the user to generate force-velocity (and thus power output curves) with minimal effort.
Up to 65000 data points per channel can be recorded, and the feedback loop can operate at rate of up to 5 kHz. The feedback gain can be varied at will allowing the user to match the system performance of their apparatus.