Underwater stability could be defined in two ways:
- When moving slowly or when stationary, what happens as it is hit by swirling water currents?
- When being driven, how smoothly does it react?
When moving slowly or stationary underwater, the primary characteristics that effect stability are:
- The sail area that the water pushes against
- The difference between the center of buoyancy and the center of drag
The sail area is another area which is somewhat difficult to minimize, but you want to avoid large flat surfaces around the outside (for example) and make exposed surfaces hydrodynamic.
The difference between the center of buoyancy and the center of drag keeps the vehicle from rocking.This is done by putting flotation as high as possible on the top, and ballast as low as possible on the bottom, and avoiding a flat shape that prevents this.
VideoRay is very stable in swirling currents particularly when compared to other ROVs because we paid attention to all these factors.That makes VideoRay more stable AND more maneuverable than competing units even those that are much larger and heavier.
So how about when it is being driven? New users often compare the way a VideoRay moves compared to other units as the difference between a performance motorcycle and a large truck. It accelerates faster, stops faster, turns faster, etc. Since it has a much higher power-to-mass ratio than others, it seems unstable until you learn to take it easy on the gas pedal. However, you soon realized you have to be careful and that all that extra power means you can work in higher currents and with more tether in the water. If you need to, you can dial down vertical power, and forward and turning power separately on the Pro 4 Cockpit software controls.