The effectiveness of disinfectant spraying based on drone technology

The disinfectant spraying activity includes a part of efforts to prevent the spread of Covid-19. Spraying is usually done by manual method. This condition results in uneven spraying and it takes a long time. So, automatic disinfectant sprayers is the way to resolve this problem. This study aims to determine the effectiveness of disinfectant spray devices based on drones. The application of automation is obtained from the use of drone technology and testing the spraying in interval time. This research is conducted by using a drone design study method and field testing. The design of the drone as a spray tool is based on the basic assembled X6 tarot framework. The drone that will be used later can lift up to 6 kg as a maximum weight. The design stage begins by conducting a literature study of the type of control use. Control settings are made by calibrating the device to the drone’s load to obtain the maximum movement. The use of drones for spraying disinfectant liquid is done by taking off using the flying mode automatically regulated through the Mission Planner software. The results showed that the prototype drone uses a 6-liter tank capacity with a flight time of 6-8. In this case, the use of drones as disinfectant sprayers can facilitate spraying activities and cut down on application time.


Introduction
There were two cases of Covid-19 that occurred in Indonesia on March 2, 2020 [1]. The increase in positive cases of Covid-19 continues to grow rapidly until the end of May 2020. Based on data reported until May 26, 2020, there were 23,165 positive cases of Covid-19 in Indonesia [2]. The implementation of disinfection is increasingly being carried out by various parties aimed at breaking the chain of transmission [3]. Disinfection is the process of reducing the possible number of microorganisms to a lower level of danger [4]. Various disinfectant spraying activities included in the part of efforts to prevent the spread of the Covid-19 virus. Spraying is usually done by manual methods. This condition results in uneven spraying and requires a relatively long time. One way to overcome this is to use an automatic disinfectant sprayer. In line with developments, unmanned aerial vehicle (UAV) is a technology that has enormous potential based on its capabilities. UAV is an aircraft that is autonomous and can be controlled manually via radio control or automatically by processing sensor data so that it can fly according to user needs [5]. One of the UAV systems, namely drones can be used for spraying activities. During the Covid-19 pandemic, the use of disinfectants had been widely applied to disinfect the surrounding environment, but spraying using automatic methods had not been widely applied. Then innovation is needed for spraying disinfectants. Through the design of a drone that is assembled with a special remote control, it aims to spray disinfectant liquid. The spray device designed has many advantages including the level of distribution of the disinfectant liquid that is sprayed more evenly, the safety factor of the sprayer because the distance between the drone and the controller can be adjusted, and minimizes the spraying time is shorter.

Methodology
The research methodology is needed in designing the drone system. The stages carried out include planning, making tools, and testing with the following explanation: 1. Stages of Planning, including drone design, selection of materials, and components. The drone system design is based on basic references in making drones. The design of the drone is based on the basic Tarot X6 framework. Drone design sketches are made using Corel Draw software, the selection of materials consists of the materials used to build the drone frame and the drone system as needed. While the selection of the right components needs to be considered in order to support system performance by producing good performance according to its function. 2. Manufacturing stages, including mechanical systems, electronic systems, and programs. Making a mechanical system that is drone assembly is based on a design drawing that has been made consisting of the dimensions of the drone framework in accordance with the plan drawings. The manufacture of an electronic system in the form of component placement must be adjusted to the drawing. Electronic components are placed on a mechanical system that has been assembled so that the electronic and mechanical components can form a unitary framework for the drone properly while the program is the structure of the work system as a whole. 3. Testing Stages, where the system will be tested after going through the planning and manufacturing stages is complete. Drone flight testing is carried out to obtain overall data when the drone is operating. If the testing phase is successful, data retrieval and analysis will be carried out.

Description of System
The drone system that works includes input, process, and output so that the drone can carry out direct flights. The input on the drone system is a remote control. In the process, there is a flight controller while the output there is an ESC which connected to each of the brushless motors. The system designed via a remote control command is then sent to the Naza-M V2 flight controller, and then the command is forwarded to the ESC to activate the brushless motor.

Figure 1. Block diagram system
The making of coordinate points was done using mission planner software. After the coordinates have been made, the pilot will send data to the flight controller. For the disinfectant, liquid is the same as when flying with GPS-hold mode, namely by pouring the disinfectant liquid into the container that is attached between the landing gear of the drone. When taking take-off using waypoint mode, the remote control is used to activate the throttle button and direct the throttle button-up (up throttle). The drone will automatically take-off and aim at the coordinates that have been made. When the quadcopter is at the coordinate point, it must activate the spray button on the remote control. Then the water-pump will be active and spray disinfectant in the intended direction until it runs out. After finishing spraying, it is necessary to turn off the spray button on the remote control. Then the drone will automatically land at the predetermined coordinate point.

Result and Discussion
Mechanical and electronic designs that have been assembled will form the drone system. In Figure 3 shown below, you can see the overall mechanical system, in making this mechanical system an aluminum frame is used as the drone frame. The frame is equipped with a brushless motor as a propeller drive. There are 6 brushless motors used. The use of arms on the drone frame is adjusted to the number of brushless motors installed which aims to increase lift on drones that have a total payload or load that is approximately 10 kg.  Based on the data in Table 2, spraying using a drone obtained an average spraying time with an experiment of 5 times, namely: Avarage = Σ / n (1) Avarage = 36,89 / 5 = 7, 38 minute (2)

Conclusion
Based on the results of testing the spray of disinfectant using drones that have been carried out, it can be concluded that the drone that has been designed is capable of flying well. However, there is a limit to the disinfectant liquid that the drone can transport, which is a maximum of 4500 ml so that the drone can take off successfully. The average spraying time obtained with a battery capacity of 22000 mAh is about 7.38 minutes. In the testing process, the remote control plays an important role in running the drone system, the components can operate according to their function and can spray disinfectant liquid. Spraying system using a drone can help in spraying easily and cut the amount of time needed.