You have a shot with the swivel to the left & one of it to the right. If you had a shot of if hanging straight down you could print all three pics as one, or mat them that way. Like this- left | middle | right -which would convey a sense of motion as the swing moves from left to right.
While a triptych is traditionally a single image divided into three parts, modern usage can be of a series of three related images printed together. Here's an example of the modern interpretation of a triptych. The pics are related to each other rather than one pic divided into three sections.