Category Archives: Blog
Computer Vision in Autonomous Landing
Computer vision and map registration enable high-precision lunar landing that wasn’t possible with the radio-based techniques during the Apollo missions. Digital cameras, computers, algorithms, and global imagery unavailable to Apollo make this now possible. Map registration is the process of matching camera image features to a pre-built database of features from a map of the… {read more}
Gravity Offload Tracking
The simulation of the Moon’s gravity is key in testing the performance of our rovers. On the Moon, an object weighs one sixth of what it does on Earth. The gravity offloader lifts five sixths of the rover’s weight by hoisting the rover from above its center of mass. Real-time tracking ensures that the lift… {read more}
Test of Polaris Swing Arm
The composite swing arm of Polaris was tested to failure. A testing rig was developed from which weight could be hung until the swing arm broke. The test rig is composed of a metal top plate bolted to an L-shaped lower metal plate (figures 1 and 2). Between these two plates is the composite swing… {read more}
Fabrication of Polaris Swing Arm
First, carbon fiber sheets are cut into strips (figure 1). The carbon fiber strips are laid out on a table and covered in resin in figure 2. The resin hardens when it cures at high temperatures in an oven. The carbon fiber and resin are covered in a sheet of plastic and the resin is… {read more}
Distribution of Error During Cruise Stage
Serial mid-course corrections direct any spacecraft to approximate a pre-computed cruise trajectory. An iterative series of corrective rocket thrusts hone in on a desired trajectory. In the case of a moon-lander, a quality cruise trajectory is essential for precise orbit insertion. Although an ideal trajectory can be pre-computed, the corrections must be planned and implemented… {read more}
Composite Testing
Variations of materials, layup techniques and process variations affect carbon fiber composite strength, so samples are tested to determine bulk properties. This video conveys testing in action. Figure 1 shows several strips after pulling to failure, and Figure 2 shows a strip in the tensile test instrument.
