The Robotic Arm will be used to excavate soil samples while scientists on Earth monitor its progress with the SSI, and a small camera attached to the arm just above the scoop, the Robotic Arm Camera (RAC). The arm's mission is to help discover the distribution of volatiles (water, CO₂) in the soil. The RA will carry the soil to the TEGA which will analyze the composition of trapped gasses in the soil. The trenches dug by the Robotic Arm will be photographed so the scientists can more closely examine layering in the soil. This layering, which occured over many years, may provide scientists with a geologic record of past events in the Martian climate.

Parts of the Robotic Arm and Their Function

• Scoop
  The scoop at the end of the Robotic Arm will dig trenches in the Martian soil. The Arm is about as strong as a human arm, and the scoop has additional teeth to aid in digging.
  
  
• Robotic Arm Camera
  The Robotic Arm Camera will take photographs of the soil at the tip of the scoop. This will help to understand the nature of the soil which has been dug.
  
  
• Elbow Temperature Sensor
  This sensor is sctually part of the MET package, but it resides on the "elbow" of the Robotic Arm. It will provide additional temperature measurements, and allow temperature measurements to be made anywhere by moving the Robotic Arm.