The Arched Brace Truss
The arched brace truss is, like the hammerbeam truss, an open arch. This type will provide a more spacious and open feel than the king post or queen post truss, which are both considered closed. The defining element is the arched braces that a horizontal collar tie rests on.
A king post isn't a structurally necessary component of this type of truss. Still, you might find that a king post is visually important as a way to emphasize the high point of the vault.
How to use it: Because an arched brace truss introduces a curve into the design, it's ideal for situations where you want to create an arch to frame the view. It's also the ideal type when you want to create the feel of a barrel-vaulted ceiling.