The Mars 2020 rover is getting ready for its trip to the red planet next year. The latest step in readying the rover is installing its wheels and suspension system, which engineers at NASA’s Jet Propulsion Laboratory (JPL) have been doing this month.
In the photo, the engineers wear protective gear to prevent any contamination as they carefully install the wheels and legs which will let the rover rove. There are six wheels in total, and you can see the textured surface which has been machined into each one. The texturing consists of 48 grousers, also known as cleats, which dig into soft sand to propel the rover forward but can also provide traction on hard rocks, letting the rover move over the variety of surfaces found on Mars.
The wheels you see in the image are engineering models, used for fitting and testing. Before the mission launches next year, these wheels will be replaced with the final flight model wheels.
Each wheel is 20.7 inches (52.5 centimeters) in diameter and has its own integrated motor to provide power to drive the rover forward. In addition, both of the two sets of front and rear wheels have individual steering motors, allowing the rover to spin in place and turn a full 360 degrees, making it highly maneuverable even in tight spaces.
The wheels are attached to two legs made of titanium tubing, which NASA amusingly described as “formed with the same process used to make high-end bicycle frames.” These legs form part of the suspension system, of a type called a “rocker-bogie” system because it has multiple pivot points. This means that the rover will stay relatively upright even when the wheels are moved into different positions and angles, which stops the rover from tipping over when it moves over obstacles like rocks, dips, and tilted ground.
“Now that‘s a Mars rover,” David Gruel, the Mars 2020 assembly, test, and launch operations manager at JPL, said approvingly in a statement. “With the suspension on, not only does it look like a rover, but we have almost all our big-ticket items for integration in our rearview mirror — if our rover had one.”