Spider strides must respect how long the water surface can sustain deformation. A fast downward impulse creates a local pressure spike that rebounds as a capillary wave. If the next stride lands before that wave decays, it adds instability instead of propulsion. Observations show an intentional phase offset between contralateral legs to spread these waves.
Stride length and frequency also balance the risk of pierce-through. Short, rapid strides keep loads low but waste distance; longer strides demand better weight distribution. Spiders tune frequency to match capillary relaxation time so the meniscus recovers before the next push.
For biomimetic prototypes, the lesson is to design controllers that throttle impulses based on surface state. A simple rule is to cap each impulse below the load that would depress the interface past the capillary length, while keeping a minimum dwell time between pushes. Sensors that track surface deflection or drag could close the loop and keep the device stable on choppy water.