236 inlet funnels on the Rover deck. The OCM is an inorganic matrix material spiked with a known  fluorocarbon calibrant. It is sampled using the Drill and processed with CHIMRA before being deposited  in SAM. It is used to assist in the validation of t he SAM science results with respect to the detection of  organics or the lack thereof. The Observation Tray is  a place where sample can be placed for viewing  with the APXS or MAHLI. The Inlet Covers are dust covers for the SAM and Chemin funnels.  

Subsystem Design and Configuration   The SA/SPaH subsystem is a highly mechanized syst em with 17 actuated degrees-of-freedom (4 on the  Drill, 4 on CHIMRA, 1 on the DRT, 5 on the Robotic Arm, and 3 on the Inlet Covers). Sixteen of the mechanisms are driven by rotary actuators consisti ng of brushless motors with planetary gearboxes, and  encoders as commutation and motor position feedback devices. Drill percussion uses a linear voice coil actuator. Many devices include pow er-off brakes. The actuators on t he Robotic Arm also have output  resolvers.  Functionality

These 17 degrees-of-freedom are used in a coordinated fashion to perform the operations used to prepare, acquire, process, and deliver samples, and to  support other activities necessary for conducting  the scientific investigation on Ma rs. The required operations are: 

• Remove dust from the surface of rocks with the DRT  • Place MAHLI and APXS on rock and regolith targets for in situ  analysis  • Acquire powdered sample from rock interiors, 20 to 50 mm deep  • Acquire regolith sample from the Martian surface  • Process the sample by sorting into fines less than 150 µm and creating up to 6 portions of  volume 45 to 65 mm 3 each  • Process the sample by sorting into fines le ss than 1 mm and creating a single portion of volume  45 to 130 mm3  • Deliver the portions of sub-150 µm sample to SAM and Chemin  • Deliver the portion of sub-1 mm sample to SAM  • Deliver the remaining sub-150 µm sample to the Observation Tray  • Use the DRT to clean the Observation Tray  • Place APXS and MAHLI on their respective calibration targets  • Acquire powdered sample from the OCM on the Rover using the Drill  • Acquire a bit from a bit box  • Open and close the Inlet Covers over the SAM and Chemin funnels   The 2-meter-long Robotic Arm places and holds t he turret-mounted tools and instruments on both rock  and regolith targets in its primary workspace and on Rover-mounted hardware such as the Observation Tray, OCM, and Bit Boxes. The Arm also repositions  the Drill and CHIMRA with respect to gravity during  their sample processing and sample flow activities. Finally the Arm brings CHIMRA into close proximity  with the SAM and Chemin solid sample inlet funnels so that CHIMRA can drop its sample portions into  the instruments. Figure 5 illustrates the Arm in representative poses for each of t hese types of activities.  Figure 5a shows operation in the primary workspace. Fi gure 5b indicates a sample processing activity. In  Figure 5c, the Arm positions the Turret near an inlet funnel.  The Turret is formed by attaching the 4 other Turret devices to the Drill. The CHIMRA is connected with a  parallel blade flexure, the DRT is connected with  a bracket, and both instruments (APXS and MAHLI)  have a vibration isolator between it  and its mounting bracket connected to the Drill. The Drill is attached  to the Arm output plate which is rotated using the Turret actuator of the Arm. It is  likely obvious by looking  at the Turret in Figure 2 that the task of confi guring and packaging the Turret was a very challenging  endeavor. The challenge is caused both by the large amount of functionality placed on the Turret and by  the number and complexity of the interactions with  the Martian surface and the Rover-mounted hardware.  Choosing this mounting scheme means that the Dr ill cannot be removed from the Turret without   NASA/CP-2010-216272