2009Forum Steadi-Newbies
Comprendre les principes d'équilibre dynamique dans les appareils photo stabilisés gimbal
Il y a 17 ans. Le matériel et les prix ont peut-être changé depuis.
Ce que le fil a révélé
- Dynamic balance is achieved when centrifugal forces acting on a spinning rig are in equilibrium, preventing the rig from tilting to horizontal orientation during rotation
- A rig with only two masses positioned for static balance will tilt horizontally when spun because centrifugal forces are not balanced, making a third mass or repositioned masses necessary
- The gimbal should be positioned slightly below the center of mass rather than at it, which allows for proper vertical balance and drop time control
- When testing dynamic balance, spinning speed should match the fastest anticipated panning speed, as faster rotation can mask imbalances that would appear at operational speeds
- Camera shape asymmetries and weight distribution irregularities require additional offset weights beyond theoretical two-mass calculations
Dépend de
- The explanation assumes perfectly balanced camera and counterweight shapes aligned with the support axis, which does not reflect real equipment
- The Merlin design may make dynamic balance difficult to achieve or tune depending on whether horizontal weight adjustment is available
- Testing dynamic balance with rotation speeds higher than intended operational speeds may mask real imbalances
- The brick-on-string analogy has limitations in fully representing gimbal dynamics