NASA's Mars 2020 rover gets wheeled up for the Red Planet
NASA's Mars 2020 rover is getting ready to roll, as engineers have installed its wheels at the Jet Propulsion Laboratory (JPL) in Pasadena, California. On June 13th, the unmanned nuclear explorer received its port and starboard legs and wheels, that will allow it to roam the surface of the Red Planet as it seeks out signs of present or past life.
Wheels may seem like a boring subject, but for the planners of the Mars 2020 mission, they're a serious bone of contention. While NASA has had a lot of success with its Mars rovers since Sojourner in the 1990s, the wheels used to propel the robotic laboratories haven't been all that they could be.
The problem is one of a trade-off. Ideally, the wheels on a rover should be large, robust, and made out of a tough material that can stand up to the rigours of the rough Martian terrain. Unfortunately, they also need to be light, compact, and not too expensive. While great strides have been made in wheel design, the Curiosity rover shows that there is still a way to go, as its wheels show increasing signs of wear as holes develop, rims buckle, and metal treads pull away.
To prevent a repeat of this situation, NASA is equipping the Mars 2020 rover with new wheels. Like the previous version, they're made of aluminum, but this time they're thicker, more solid, narrower, and have a wider diameter of 52.5 cm (20.7 in). This means that each turn of its six wheels carries the rover 1.65 m (65 in). Each wheel is independently powered, and has 48 cleats for better traction. In addition, the front and rear wheels have their own steering motors and can turn a full 360 degrees.
The wheels are installed on a rocker bogie suspension similar to that used on Curiosity. This results in the rover being able to handle a 45-degree incline while hitting a blistering speed of 152 m/h (499 ft/h).
"Now that's a Mars rover," says David Gruel, the Mars 2020 assembly, test, and launch operations manager at JPL. "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."
Ironically, the newly-installed wheels will not actually fly to Mars. Instead, they will be used for testing the rover and then replaced with new wheels, before the mission launches from Cape Canaveral Air Force Station in July 2020.