|Spacecraft: Surface Operations: Rover
The rover´s "neck and head"
What looks like the rover "neck and head" is called the Pancam Mast Assembly. It stands from the base of the rover wheel 1.4 meters tall (about 5 feet). This height gives the cameras a special "human geologist´s" perspective and wide field of view.
The pancam mast assembly serves two purposes:
- to act as a periscope for the Mini-TES science instrument that is housed inside the rover body for thermal reasons
- to provide height and a better point of view for the Pancams and the Navcams
Essentially, the pancam mast assembly enables the rover to see in the distance. The higher one stands, the more one can see. You can test this out for yourself by lying on the ground and observing as much as possible, then standing up and seeing the difference in the amount of greater detail you can observe about the world with a broader field of view.
One motor for the entire Pancam Mast Assembly head turns the cameras and Mini-TES 360º in the horizontal plane. A separate elevation motor can point the cameras 90º above the horizon and 90º below the horizon. A third motor for the Mini-TES elevation, enables the Mini-TES to point up to 30º over the horizon and 50º below the horizon.
During cruise, the Pancam Mast Assembly lays flat against the top of the rover equipment deck in a stowed configuration. After the lander opens on the surface of Mars, pyros release the bolts holding it down . Pyros are solid mechanical devices that contain as much power as a bullet release mechanism in a gun. Pyros were designed in the 1960s for the Apollo mission as a safe way to release bolts and strong devices on spacecraft while humans were in the vicinity.
The Pancam Mast Assembly rises from the rover equipment deck by driving a motor that moves the Pancam upward, in the shape of a helix. It sweeps out in a cone-like manner as it deploys. Once the Pancam Mast Assembly is in its full-upright position, it does not stow again, but stays upright for the entire duration of the mission.