Our 315D & 322D models of High-Speed Length Controllers are routinely used by researchers studying small tissue samples such as fibers and cells because these instruments offer very high positioning accuracy (better than 1um) with a very fast response time. However, to leverage the usefulness of this positioning accuracy we must calibrate these length controllers precisely.
Recently, we published a blog which details how to calibrate our Dual-Mode Lever Systems. To measure changes in length with the Dual-Mode we mark a piece of paper or tape and measure the length change with a vernier caliper. However, the High-Speed Length Controllers are much smaller than the lever system motors and much more difficult to mount in this way. Additionally not all models have a hole in the tip of the arm and thus it is hard to make the marks as accurately. What we require is an optical method of calibrating these smaller motors. Fortunately, such a method exists.
Many of our high-speed length controllers are sold as part of our 1400A or 1600A systems. These systems are all equipped with our High-Speed Video Sarcomere Length program or HVSL for short (link). When the length controller is mounted as part of the system onto your inverted microscope, we can use the ‘markers’ function in the HVSL software to accurately measure the displacement of the length controller or its hook attachment.