Two of the raised treads, called grousers, on the left middle wheel of NASA's Curiosity Mars rover broke during the first quarter of 2017, including the one seen partially detached at the top of the wheel in this image from the Mars Hand Lens Imager (MAHLI) camera on the rover's arm.
This is a closeup view of the wheels on the Scarecrow mobility rover. Scarecrow is Curiosity's test double that engineers use for testing such as this drive over dunes in the Dumont Dunes in California's Mojave Desert, near Death Valley.
This view of the three left wheels of NASA's Mars rover Curiosity combines two images that were taken by the rover's Mars Hand Lens Imager (MAHLI) during the 34th Martian day, or sol, of Curiosity's work on Mars (Sept. 9, 2012).
In the Payload Hazardous Servicing Facility at NASA's Kennedy Space Center in Florida, a technician inspects beneath NASA's Mars Science Laboratory (MSL) mission aeroshell, (containing the compact car-sized rover Curiosity), which has been mated to the cruise stage.
This photograph of the NASA Mars Science Laboratory rover, Curiosity, was taken during mobility testing on June 3, 2011. The location is inside the Spacecraft Assembly Facility at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
In this picture, the Curiosity rover is sitting on top of six shiny wheels. The picture was taken from the side of the rover and only four wheels are visible. The wheels have a black coating which makes them slip resistant. On the right of the rover is an engineer who is wearing a white 'bunny suit' to prevent him from getting any unwanted Earth microbes onto the rover. The engineer is holding one of the lift cables used to put the rover onto the wheels. A pink heavy-lift crane is visible over the rover. The crane is used to lift the rover body within the room. Behind the rover, lots of lab equipment and other parts are scattered around the cleanroom.
In the middle of this image, three wheels are shown raised by a lift, with engineers on both sides of the wheels in the cleanroom, where the Curiosity rover is being assembled. The wheels are made out of aluminum but have a black coating, which prevents the wheels from slipping. The wheels are attached to dark poles, which bend like 'joints.' Several black and red cable wires are visible coming out of the poles. An engineer stands in the background holding a clipboard and looking closely at the rover. A desk and various tools are visible behind the wheels on the right.
The team developing NASA's Mars Science Laboratory calls this test rover "Scarecrow" because the vehicle does not include a computer brain. Mobility engineers use this test rover to evaluate mobility and suspension performance.