2. Ramp width, lip measurement and slope of ramp can successfully be extracted from both LiDAR scanner and Structure Sensor. This finding is significant given the length of time required to collect these measurements. In addition, team members noted a self-conscious feeling when bending down, pulling out a tape measure, and measuring curbs in a busy street. It was noted that 3D, sensor-based data extraction may overcome this. Structure Sensor scans took our team members 5 minutes but further product development could reduce this significantly. It was noted that volunteers may be able to extract physical measurements of built environment features more effectively using a 3D scanner than by using a tape measure, since sensor use does not evoke the same feelings of awkwardness (or risk of tripping up pedestrians) that use of a tape measure creates. For wheelchair users interested in crowd-sourcing accessibility data, it was noted that sensor use may be feasible whereas manual measurements are not.
4. Structure Sensor demonstrates the viability and utility of 3D sensing for streetscape features. This is important given future 3D-scan smartphone capabilities.
5. Because of structure sensor is based on Infrared technology, so it requires weather as sunny days which have enough light and minimum street water deposit reflection. 

Recommendation and preliminary design for 3D-enabled smartphone app

  • App should combine the field survey method with 3D imagery capture.
  • Design criteria: Require user to enter bare minimum of data, lowering the time requirement below ‘pain threshold’ and allowing for a large user base.