**4.3 Extending the possibility of patrolling by remote sensing to the third dimension**

As a next step, we can unlock the criteria for monitoring in two-dimensional area or standard but relatively at low-altitude (1500 m) observation. Based on it we can examine how the results change if we extend the possibility of patrolling to the third dimension. In this case we use the aerial autonomous systems like UAVs or drones as it was explained in the previous subchapter where 1500 m altitude was used. In this example we assume the same observation area that is 576 km<sup>2</sup> , the same maximum patrol speed that is 180 km/h, and the standard camera angle view that is 90°. However, we modify now the altitude of the flight path using 1500 m basic level—as it was in the previous subchapter—and raise it with double steps as well as 1500, 3000, 6000, and 12,000 m. Based on these conditions, the results are shown in **Table 3**.

It can be seen that by increasing the flight altitude, the ratio of the time under observation increases exponentially comparing to the total flight time. Non-observation time reduces in the same way but with the opposite direction as shown in **Table 3**.


**Table 3.**

*The effect of flight altitude of autonomous system for flight path.*

#### **Figure 8.**

*Changing flight altitude moves the flight path in to the centre of the observed area.*

**Figure 9.** *Higher observation altitude means that the flight path will move to the centre of the given area.*

Taking the forest fire detection as an example, the efficiency criterion is 15 min. This overflying time above the same point (pixel) can be assured at 6000 m flight altitude, ignoring the fact that the observation time ratio in this case is ¼. Increasing the observation altitude, the size of the observed area unit also increases. As the sample area is delimited, the centre of the larger area unit and the route of the patrol are moved toward the centre of the area as shown in **Figures 8** and **9**. In the "D" case of **Table 3**, we can see that by increasing the altitude, there is a point where the whole area can be monitored continuously.

Practically, the results are the same as we could see at the process of raising the camera angle view at the previous subchapter. Obvious changes of the flight paths are also the same in both cases as it can be seen in **Figures 6** and **8** as well as in **Figures 7** and **9**. Both in raising the flight altitude and the camera's angle view the efficiency of the detection increases significantly.

According to the example, the continuous monitoring was materialized quite high, that is, at 12,000 m. The possibility of it can be carried out by a mediumaltitude long-endurance (MALE) or high-altitude long-endurance (HALE) unmanned aerial vehicle (UAV) or system (UAS). Moreover, it can be served even by satellite-based monitoring systems.

**113**

**Figure 10.**

*Path Planning Optimization with Flexible Remote Sensing Application*

**4.4 Comparing the mobile and stabile remote sensing applications**

The effect of raising the camera angle of the autonomous system or the flight altitude of the aerial autonomous systems, like drone, UAV, or UAS results in the same effect meaning that the path will move to the centre of the responsible area.

The results from the increase of the flight altitude and of the camera angle, logically, will lead to further ascertainment. In both cases, the entire area can be observed simultaneously. This point locates in the centre of the area. From the data we can see that the speed value belonging to the centre point is zero. This is a very special situation: The camera of the autonomous system, as a monitoring device, does not require any movement, i.e. patrolling. The values in line "D" of **Table 2** and **Figure 7** show the increase of the camera's angle view—which justifies the full observation of the area—can be ensured if the observation is not only from the same point but also from the same height! This statement proves that the application of the mobile autonomous system with the help of a stable or fixed installed autonomous system—in case of a flat area—can be theoretically triggered.

The characteristics of the function between the monitored pixels and flight altitude (left) or camera's angle view (right) can be seen at **Figure 10**. In both cases we can see that there is a value where all pixels—which means the whole area—are

The comparison analysis based on economic base of the abovementioned ascer-

1.The camera, as a remote sensing device, would be present in both test lines, with approximately the same values in its technical parameters. Technically

2.According to **Table 2**, the fixed-system monitoring rate is apparently full, so the comparison with the use of a mobile device is definitely a disadvantage of

3.While using a fixed installation system, we should choose the solution, when the camera does not see the whole area at the same time but detects it moving

*Rate of blind and observation area depending on raising the flight altitude (left) and the camera angle (right).*

*DOI: http://dx.doi.org/10.5772/intechopen.86500*

under observation in the same time.

this would not cause a significant difference.

tainment gives results as follows:

the latter.

*Path Planning for Autonomous Vehicles - Ensuring Reliable Driverless Navigation...*

**Ao (km2 )** **l (km) Lp**

A 180 1500 90 9 3 192 64 1 63 1/64 B 180 3000 90 36 6 96 32 2 30 4/64 C 180 6000 90 144 12 48 16 4 12 16/64 D — 12,000 90 576 24 — — Cont. — 64/64

**(km)**

**tp (min)**

**to (min)**

**tblind (min)** **Ro (−)**

**Value event**

**Table 3.**

**Figure 8.**

**Figure 9.**

**Vp (km/h)** **Hp (m) α<sup>D</sup> ( 0 )**

*The effect of flight altitude of autonomous system for flight path.*

*Changing flight altitude moves the flight path in to the centre of the observed area.*

Taking the forest fire detection as an example, the efficiency criterion is 15 min.

Practically, the results are the same as we could see at the process of raising the camera angle view at the previous subchapter. Obvious changes of the flight paths are also the same in both cases as it can be seen in **Figures 6** and **8** as well as in **Figures 7** and **9**. Both in raising the flight altitude and the camera's angle view the

According to the example, the continuous monitoring was materialized quite high, that is, at 12,000 m. The possibility of it can be carried out by a mediumaltitude long-endurance (MALE) or high-altitude long-endurance (HALE) unmanned aerial vehicle (UAV) or system (UAS). Moreover, it can be served even

This overflying time above the same point (pixel) can be assured at 6000 m flight altitude, ignoring the fact that the observation time ratio in this case is ¼. Increasing the observation altitude, the size of the observed area unit also increases. As the sample area is delimited, the centre of the larger area unit and the route of the patrol are moved toward the centre of the area as shown in **Figures 8** and **9**. In the "D" case of **Table 3**, we can see that by increasing the altitude, there is a point

*Higher observation altitude means that the flight path will move to the centre of the given area.*

where the whole area can be monitored continuously.

efficiency of the detection increases significantly.

by satellite-based monitoring systems.

**112**

The effect of raising the camera angle of the autonomous system or the flight altitude of the aerial autonomous systems, like drone, UAV, or UAS results in the same effect meaning that the path will move to the centre of the responsible area.
