Here's the backstory:
The Hudson-class is a descendant of the earlier Danube-class, and is similar in size, and capacity, while offering improved range and speed, with a maximum of Warp 9.1. The more angular appearance of the Hudson-class vessels is due to the use of a stronger, more rigid space frame which, in conjunction with more powerful warp engines derived from those found on the larger Defiant-class vessels accounts for the increase in speed. The larger size of the now-shielded warp coils made in necessary to relocate the impulse drive to separate pods above the main warp engines. While the Hudson-class vessels share the modular construction of the earlier Danube-class, most of the vessels built early in the production run were preassigned to dedicated functions and constructed at the shipyard in such a way that it precludes them from being reconfigured.
During the Hudson-class' early stages development, a need arose for several small ships to be assigned to Starfleet Headquarters for use as diplomatic couriers and transport vessels, and several of the Hudson-class vessels were requisitioned for this purpose. These ships were assigned Starfleet Command registries and wore a different livery that the standard Starfleet vessels. The U.S.S. Hudson, during its testing phases, was the only ship of the class to wear both liveries, and for a time wore a mix of the two, though it retained its NX registry designation throughout.
This model began as a side-effect of my larger Jefferies-class Frigate project, when I began playing with docking ports on the rim of the larger ship's primary hull. I thought it would be cool to include a Runabout type of ship which could be docked to the ship.
By this point, I was well into the design of the frigate, and had already roughed in the basic shape of the shuttlecraft for the open shuttlebay, so it wasn't too difficult to double the little shuttle design in size and dress it up a bit as a new class of Runabout. I liked the finished look of the tiny, little ship so well, that I decided to do a larger, better detailed version, and that's what we've got here. I've added separate parts for many of the surface details to break up the texture a bit, but I'm sure that a few builders I know will take it far beyond what I've done.
When it came time to name the ships of the class, I made a list of all of the possible names for runabouts that hadn't been used on Deep Space Nine, and the first two river names that came to mind were the Hudson, and the Jordan. These also just happen to be the names of old cars, so while I started with good intentions, I quickly decided to satisfy my own sense of humor, so all of the Hudson-class ships are named after old cars, instead of rivers....