Spacecraft Azimuth Variations

Aim and Objectives

Purpose of Test 11: To evaluate SPC's ability to represent a simplified 'boulder' which has a constant 20 degree slope.

Objective for Tests 11 F, G, H, I &J, Spacecraft Azimuth Variations

To investigate the effect of varying the combination of spacecraft azimuths with respect to a landmark contained in the image suite;

To investigate the effect of the number of images and viewing conditions.

Methodology

The 'boulder' was simulated by generating a simple axi-symmetric, flat-topped cone (peak) with a constant 20 degree slope. Multiple peaks and (simplified) craters are randomly placed in an otherwise flat landscape of width approx. 22.5m.

Entire Truth map: REGION.MAP

Bigmaps

The following TAG1 bigmaps were tiled/iterated and evaluated:

Starting topography defined from: START1.MAP at pixel/line location 49, 49 (= REGION.MAP at p/l 1125, 1125).

Step	GSD	Overlap Ratio	Q Size	Width	Center
START.MAP	20cm	-	49	20m	REGION.MAP p/l 1125, 1125 (center)
10cm-Tiling	10cm	1.3	130	20m	START1.MAP, p/l 49, 49
5cm-Tiling	5cm	1.3	250	20m	START1.MAP, p/l 49, 49
5cm-Iterations	5cm	-	-	20m	START1.MAP, p/l 49, 49
Portion Truth Map (011TRU.MAP)	1cm	-	200	4m	REGION.MAP, p/l 996, 1005

Tiling/Iteration Parameters

Auto-Elimination Parameters:	0, 60, .25, .25, 0, 3
Reset albedo/slopes	NO
Determine Central Vector	YES
Differential Stereo	YES
Shadows	YES

Tiling seed files: t11-10.seed , t11-05.seed

Iteration seed file : Piteate2StSh-woAYY

Data

Data was generated by Eric.

Image resolutions: 2cm/pixel.

Viewing Conditions

Name	Sun	S/C Az	S/C Zenith	Total Number of Images
Test11F	45, 0, -45	every 20	45	72
Test11G	45, 0, -45	every 30	45	48
Test11H	45, 0, -45	every 45	45	32
Test11I	45, 0, -45	every 60	45	24
Test11J	45, 0, -45	every 90	45	16

Test 11F Viewing Conditions

Test 11G Viewing Conditions

Test 11H Viewing Conditions

Test 11I Viewing Conditions

Test 11J Viewing Conditions

Results ( All with overlaps)

Test Over11FGHIJ Comparative Results

Test Over11F Results

Test Over11G Results

Test Over11H Results

Test Over11I Results

Test Over11J Results

IMPORTANT Note: The heat maps are made from CompMapVec where optimal translation and rotation is not used.

Heat Maps Discussion

Observing the heat maps show a clear tilt that is present since one side of the Effort's bigamp topography is always lower than the Truth's after the tiling step. Then, as iterations occur, SPC starts to bring the entire topography up to account for this tilt, but SPC overshoots the Truth leaving most of the Effort's topography now greater than the Truth. The heat maps also indicate the iterations where the Effort's topography best matches the Truth; which are 10 ,20, 20, 30, and 30 for Tests F, G, H, J , and I respectfully. This completely agrees with Figure 1 in the Test Over11FGHIJ Comparative Results Section.