## 4 Results
### Quadruped Robot Dog and Networked External Sensor Circuit for Air Quality Monitoring  
The results of the QRD air quality monitoring in confined space are captured by a sensor board that transmits data via a Wi-Fi connection and uploads it to a database. This enables near-real-time, interactive monitoring of the sensor measurements. Using Grafana for data visualization enhances this process, offering an intuitive view of all sensor data. Since all components are locally hosted and data transmission occurs through a local wireless network, the sensor data remain confined to the host and client interaction, ensuring their privacy. Figure 10 shows a Grafana Dashboard with three different elements: (1) a near-real-time graph that simultaneously visualizes sensor data, and each one of these readings can be toggled for an individual view of the sensor data, (2) an enlarged numerical panel that highlights the most recent sensor outputs, and (3) a detailed table presenting a list of collected sensor readings. As InfluxbB is time-based, each sensor batch is indexed via time within the \"Sensor Data Tabulation\" and within the structure of the database itself. Each sub-panel within this Dashboard displays specific data based on individualized queries into the locally hosted InfluxbB database. It is therefore important to keep database queries efficient. In this specific snapshot, the QRD maneuvered into the CO\({}_{2}\) testing confined space and detected the transmitted elevated CO\({}_{2}\) corresponding to deliberate release of CO\({}_{2}\) via a valve. A remote operator can see the environmental context in which CO\({}_{2}\) measurements are taken. Quadruped Robot Dog Floor Mapping with Infrastructural Acoustic Analysis and Low-Light Visual Inspection  
In this section, the result of the QRD LiDAR mapping experiment is compared with the original floor plan. Figure 11 shows the floor plan of the building overlaid with the map received by RViz from the QRD floor survey. As displayed in Figure 11, the robot was able to cover all the area and determine the walls accurately. This ensures that the human user receives gathered data and safety information that spans the entire building floor. Using the Canny edge detection algorithm [56], the floor plan was compared with the QRD LiDAR map by calculating the similarity of the given edges using the ratio of the sum  
Figure 10: A sensor application reporting telemetry from a sensor board mounted on QRD in near-real time. It consists of a graph in the top left corner, the most recent data readings in the top right corner, and a data tabulation in the bottom half (Figure edited for clarity). of the pixel intensity square valued to be 1.0858, in which the values closer to 1 indicate more similarity between the images. As many homes use pumps to circulate water for heating and cooling, the results of this section are crucial in verifying the application of this framework in detecting early signs of damage in the pump. The QRD enters through a small rectangular opening and inspects a pump in low-light conditions. An infrared LED camera and microphone collect data to analyze the frequency of the pump cycling on and off, using MATLAB to create a spectrogram. Figure 12 shows the visual live stream of data in low-light conditions that are clearly visible to the user viewing it in AR for a safety inspection. Figure 13 shows that the pump was turned on for about 13 s.  
The acoustic data are recorded using a sampling rate of 44,100 Hz to capture the cycling of the pump. Figure 13 demonstrates the changes in the spectrogram of the pump with data acquisition occurring with a 1-year gap. Comparing the spectrogram of the water pump over time shows the changes in power over frequency. This could indicate the mechanical components of the water pump are vibrating at different frequencies, in which the great differences may imply a damaged pump and require a detailed inspection to prevent failure of the system. Figure 11: A comparison of the floor plan with the QRD LiDAR mapping.