The Robotic Arm that uncovered water ice on Mars.
The development of the Phoenix Mars Lander’s Robotic Arm (RA) was a collaborative effort between NASA’s Jet Propulsion Laboratory (JPL), Alliance Spacesystems and Honeybee Robotics. Dr. Robert Bonitz of JPL oversaw the development of the RA’s control avionics, flight software, biobarrier and integration and testing. Alliance Spacesystems was responsible for the design of the arm; while, Honeybee Robotics built the scoop of the arm.
Prior to the Phoenix, JPL had constructed the design for the RA of the Mars Polar Lander; and Alliance Spacesystems had previously developed the RAs for the Mars 2001 Lander and Mars Rovers, Spirit and Opportunity. The Phoenix’s RA was designed similarly to the RA of the Mars Polar Lander. The Mars Polar Lander’s RA underwent testing in Death Valley where it dug 10 inches deep in under 4 hours of its mission. The testing conducted at Death Valley mirrored Phoenix’s excavation of Mars. The testing allowed scientists to model, design and prepare Phoenix for Mars’s Green Valley.
The RA was specially designed with what scientists called “four degrees of freedom.” The RA had four maneuvers which were up and down, side to side, back and forth, and rotate around. These maneuvers gave Phoenix the freedom to scoop out the appropriate amount of Martian soil and water ice to analyze Mars’s environment.
The RA was approximately 8 feet long with a scoop developed by Honeybee Robotics that contained blades and sharp prongs. The blades and prongs were attached to the end of the scoop to scrape the Martian soil and ice. The arm was 1.6 feet long, which allowed Phoenix to scrape deep enough below the subsurface of Mars to contact water ice.
The design of the RA was paramount to the objectives of the lander. The RA was designed to excavate and sample Martian soil and water ice. Phoenix used its Icy Soil Acquisition Device to collect the samples which were then analyzed by its Thermal and Evolved Gas Analyzer and Microscopy, Electrochemistry and Conductivity Analyzer for its chemical and geological composition.
As Phoenix dug through the surface of Mars, its Robotic Arm Camera captured the processes and ultimately revealed one of Phoenix’s most compelling discoveries….