Accuracy and utility of the Structure Sensor for collecting 3D indoor information

Figures & data

Figure 1. Illustration of Structure Sensor.

Table 1. Structure Sensor specifications.

Parameter or specifications	Value or description
Length × Width × Height	119.2 mm × 27.9 mm × 29.0 mm
Min/Max sensing distance	40/350 cm
Resolution for depth data	VGA (640 × 480) QVGA (320 × 240)
Frame rate	30/60 fps
Power source	USB charged battery with 3–4 h of active sensing
Data transfer	Wi-Fi/USB
Field of view	58° Horizontal and 45° Vertical standard lens
System on a chip (SOC)	Prime Sense chip (Heindl 2014)

Figure 2. The geometry of converting disparity to depth.

Note: Adapted from Khoshelham and Elberink (2012).

Table 2. Case study rooms’ specifications (unit: m).

Case no.	Dimensions	Height
Room 1	6.54 × 6.29 × 4.61 × 4.55	2.90
Room 2	3.98 × 3.46 × 4.2 × 4.08	2.48
Room 3	2.13 × 3.30 × 3.32 × 3.32	2.46

Figure 3. Room 1 raw 3D models resulted with different data-capturing strategies. (a) one wall at a time; (b) 3×3 photogrammetry approach (Waldhäusl and Ogleby 1994); (c) circular trajectory; (d) half of the room at a time.

Figure 4. The 3D model for each study case and its 2D floor plan. (a) Room 1; (b) Room 2; (c) Room 3.

Figure 5. Absolute errors distribution for each scanned room in meter.

Figure 6. Relative fit of models’ measurements to existing data.

Figure 7. Vertical bands as artifact of the sensor. (a) Uncertain areas in depth image of the monitors near the window; (b) Parallel bands artefact shown at an approx. two-meter range from the door wall and coarse geometry due to high range value.

Table

Room No. / Measurement		Existing model	Raw model	Ae	Re
Room 1	Wall 1	6.544	5.776	0.768	0.117
	Wall 2	6.295	4.283	2.012	0.320
	Wall 3	4.607	3.359	1.248	0.271
	Wall 4	4.559	4.225	0.334	0.073
	Height	2.887	2.730	0.157	0.054
Room 3	Wall 1	2.130	2.109	0.021	0.010
	Wall 2	3.330	3.173	0.157	0.047
	Wall 3	3.320	2.730	0.590	0.178
	Wall 4	3.320	3.096	0.224	0.067
	Height	2.460	2.404	0.056	0.023
Room 2	Wall 1	3.980	3.763	0.217	0.055
	Wall 2	3.460	2.650	0.810	0.234
	Wall 3	4.200	3.710	0.490	0.117
	Wall 4	4.080	3.370	0.710	0.174
	Height	2.480	2.250	0.230	0.093
RMSE			0.742
MRE %			12.217
S^2			0.853
S			0.924		0.091

Heindl, C. 2014. Structure.io Sensor in ReconstructMe. Accessed September 20 http://reconstructme.net/2014/07/29/structure-io-sensor-in-reconstructme/

 Google Scholar

Khoshelham, K., and S. O. Elberink. 2012. “Accuracy and Resolution of Kinect Depth Data for Indoor Mapping Applications.” Sensors 12 (2): 1437–1454.10.3390/s120201437

 PubMed Web of Science ®Google Scholar

Waldhäusl, P., and C. Ogleby. 1994. “3×3 Rules For Simple Photogrammetric Documentation Of Architecture.” International Archives Of Photogrammetry and Remote Sensing 30: 426–429.

 Google Scholar