8.6. Mars Exploration Rovers

The Mars Exploration Rovers (MER) have several cameras on board and they all seem to have a stereo pair. With ASP you are able to process the PANCAM, NAVCAM, and HAZCAM camera images. ISIS has no telemetry or camera intrinsic supports for these images. That however is not a problem as their raw images contain the cameras information in JPL’s CAHV, CAHVOR, and CHAVORE formats.

These cameras are all variations of a simple pinhole camera model so they are processed with ASP in the Pinhole session instead of the usual ISIS. ASP only supports creating of point clouds. The *-PC.tif is a raw point cloud with the first 3 channels being XYZ in the rover site’s coordinate frame. We don’t support the creation of DEMs from these images and that is left as an exercise for the user.

An example of using ASP with MER data is included in the examples/MER directory (just type ‘make’ there).

See Section 8.12.5 for an analogous example for the MSL Curiosity rover using CSM cameras, and Section 9.3 for a processing example for MSL based on Structure-from-Motion.


All of these cameras are processed the same way. We’ll be showing 3D processing of the front hazard cams. The only new things in the pipeline is the new executable mer2camera along with the use of alignment-method epipolar. This example is also provided in the MER data example directory.


Fig. 8.4 Example output possible with the front hazard cameras. Commands

Download 2f194370083effap00p1214l0m1.img and 2f194370083effap00p1214r0m1.img from the PDS.

ISIS> mer2camera 2f194370083effap00p1214l0m1.img
ISIS> mer2camera 2f194370083effap00p1214r0m1.img
ISIS> parallel_stereo 2f194370083effap00p1214l0m1.img     \
                      2f194370083effap00p1214r0m1.img     \
                      2f194370083effap00p1214l0m1.cahvore \
                      2f194370083effap00p1214r0m1.cahvore \

See Section 6 for a discussion about various speed-vs-quality choices.

It is suggested to filter out points that are not triangulated well because they are too close to robot’s camera or are extremely far away, using the parallel_stereo options:

--universe-center camera --near-universe-radius 0.7 \
   --far-universe-radius 80.0

These are suggested as well:

--alignment-method epipolar --force-use-entire-range