• Atuchukwu, A. J.,  Atanmo, P.N.,  Eme, L.C.,  Joe-Ikechebelu, N. N.,  Babayemi, A. K.,  Nwabueze, C.A.,  Owuama, K.C.,  Iloh, J.P.,  Ezeugo, J.,  Akaneme, S.,  Okwuowulu, C., &  Ezechukwu, E.

Faculty of Engineering, Chukwuemeka Odumegwu Ojukwu University (COOU), Uli Campus.

Nigeria Coalition of Ecosocial Health Research (NCEHR), Awka, Anambra State.

Faculty of Medicine, Community Medicine, and Primary Health Care, COOU, Amaku-Awka Campus.

 

Corresponding Author: Eme, L.C

 

Abstract

Disinfecting machines that are available in Nigeria have been found to be unaffordable because the fabricated materials are from sources outside Nigeria.

The aim of this research project is to design and fabricate an effective solar-powered automated disinfecting system for the COVID-19 pandemic prevention in Anambra state. The objectives of the project are: (i) to optimize locally selected materials for various parts of the machine, (ii) to design and incorporate an automated operation of the machine using artificial intelligence (AI) that can realize a 100% non-contact system, (iii) to reduce the transmission of the coronavirus through personal hygiene, and (iv) to promote the use of the machine for effective prevention.

The method used was the system engineering approach which includes: use of cost-effective locally available material and a team of public health professionals of engineers, scientists, and technologists were tasked to design and fabricate a solar automated disinfectant system with an interactive user interface of four adjustable timers with beaming infrared lights within one month.

The result of the findings showed that when the machine is subjected to series of technical trials with optimizing of the components, the correlation of the model and the prototype using Pearson moment product correlation was (r = 1.0), which is interpreted as a 100% performance. Further, the fabricated experimental model showed a multipurpose machine with various operational stages from the supply of soap and water to the drying and sanitizing of the hands within 20 seconds per person at a cost of N80,000 to N250, 000 (USD$210 – $657) per unit cost for use in communities. The disinfectant machine through mass production will be deployed to communities after commissioning of the machine by the state. Apart from the recommendation to communities who will need this machine, it is expected that the project will help to hasten future challenges associated with lockdown or slow down, and to reduce economic losses from the COVID-19 pandemic.

 

Keywords: Machine, Sensors, Solar, Powered, and Hand Wash.

 

Introduction

Nigeria is presently faced with the challenge of coping with the demand for personal protective equipment (PPEs) and other necessary facilities for fighting the COVID-19 pandemic. One of such facilities is the automatic non-contact hand washing and sanitizing machines. At present, the common hand sanitizing practice is such that the user opens the dispensing taps with an unwashed hand and after washing the hand, the user uses the same washed hand to close the tap earlier touched with the unwashed hand thereby re-contaminating the hand. With this practice, there are still chances that users of such washing machines can transmit or contract the coronavirus through contact with the dispensing taps. Several attempts have been made by researchers and fabricators towards developing locally made non-contact versions of the handwashing and sanitizing machines. However, Anambra State requires cost-effective machines that are actually serving the desired purpose of washing and sanitizing the hands in a non-contact fashion.

 

Statement of Problem

There are noticeable design flaws associated with most of the machines in Nigeria, which include improper selections of materials, waste in terms of size and machines, poor ergonomics, provision for automatic operation, poor finishing, the exorbitant cost of the finished product, and poor prospects for mass production technology and uptake. Thus, there is a need for the development of a non-contact hand washing and sanitizing machine engineered to address these flaws within our Anambra state’s public health system.

 

Aim/Objectives

This research investigated a solar-powered non-contact handwashing and sanitizing machine. It is solely aimed at designing and fabricating an effective solar-powered automated disinfecting system for the COVID-19 pandemic prevention in Anambra state. The objectives of this project are: (i) to optimize locally selected materials for various parts of the machine, (ii) to design and incorporate an automated operation of the machine using artificial intelligence (AI) that can realize a 100% non-contact system, (iii) to reduce the transmission of the coronavirus through personal hygiene, and (iv) to promote the use of the machine for effective prevention. These aims are necessary because of the problems associated with improper selection of production materials, wastages in terms of size and machines with associated challenges from poor ergonomics, the exorbitant cost of the finished product, and poor prospects toward mass production technology, which make the disinfecting machine in Anambra state to be unaffordable. Further, it is imperative to educate the community about the machine and to reinforce the importance of effective handwashing as part of personal hygiene using health promotional activities.

 

 

Methodology

This project used a system engineering approach that is cost-effective and a team of public health professionals tasked to design and fabricate the machine within one month to quickly be deployed to combat the COVID-19 pandemic using locally resourced materials. It involves the design and incorporation of a non-contact thermometer to measure body temperature as well as apply the principle of engineering ergonomic to ensure optimal use of the machine; to evaluate the performance of the machine in relation to the existing local counterparts and finally to carry out a cost-benefit analysis for the machine to determine its viability for mass production with Pearson moment product correlation and optimization models.

 

Discussion of Operation of the Machine

The machine is a 4-in-one functional system that detects the presence of hands, dispenses soap first, followed by water for washing the hands after which it dries the hands, and finally applies hand sanitizing liquid on the dried hand. The machine has four sensing units. Each of the sensing units has a light-dependent resistor (LDR) and a LED laser light. The LDR is fixed inside the horizontally placed cylinder with a small hole drilled on the cylinder for passage of light from the LED laser light. LED light is fixed at the base of the wash hand basin such that light from it is focused on the LDR through the hole. Once the machine is turned on, the light continuously strikes the LDR. The sensing units are designed to work as dark operated units. In essence, the actuating signals from the sensing units are only sent when an obstacle (in this case, a human hand) is placed in between the LDR and the LED laser light thus blocking the light from reaching the LDR, causing the system to sense darkness. Once this happens, the control circuit carries out the necessary action depending on the particular sensing unit that sent the actuating signal. The four sensing units are designed such that each of them sends its actuating signal in a pre-defined sequence numbered 1-2-3-4. Sensing units numbered 1,2, and 4 are each connected to the circuit operating the 12V DC submersible pump for applying soap, water, and sanitizer respectively, while the sensing unit numbered 3 is for actuating the hand drying circuit operating a 12V DC  fan and a 20W DC heating element. The system is powered from a 12V 18AH battery bank which is regularly recharged through the 54 watts solar panel. The machine is designed as a standalone system with all the component parts including the containers for the soap, water, and sanitizer housed inside one chamber. However, a provision is made for connecting the water inlet and outlet pipes to the water supply system of an existing building.

 

Conclusion 

The results of the experimental models show that the multipurpose machine with the following operational stages: soap supply, water supply, hand drying, and sanitizing for mass production, about N80,000 – N250,000/unit (USD $210-$657 from www.xe.com). The faculty has the capacity to produce 10 units monthly. The prototype machine was subjected to a series of technical trials, optimization of components, and correlation of the model and the prototype. The performance between the model and prototype using Pearson moment product correlation was (1.0), which is interpreted as 100% performance. More so, the disinfectant system is fully automated with an interactive user- interface with four adjustable timers with infrared lights beaming continuously; the power supply is solar with a rechargeable battery. The targeted users of the recommended machine are targeted to different communities, such as schools, places of worship, hospitality industries. However, social promotional activities, such as public health education and media promotion are yet to be conducted.

 

The research is expected to provide a response to the acute shortage of affordable automatic non-contact hand washing and sanitizing machines for fighting the COVID-19 pandemic and similar outbreaks of other infectious diseases. The prototype developed will be patented for mass production for use in communities, such as schools, offices, homes, markets, and other public and private places where the regular hand-washing practice is needed to help combat the COVID-19 pandemic as well as to generate huge revenue and job creation in the economy of Anambra state.

 

Acknowledgment

We acknowledge, with appreciation, the team of public health professionals, who contributed so much of their time and knowledge with amazing and engaging insights to make this dream come through. We would also like to acknowledge and thank the leadership team of COOU: the former Dean of Engineering, Atuchukwu A. J., the Deputy Vice-Chancellor, Idemobi E., and the Vice-Chancellor, Nwakoby G., for their support and encouragement.

The prototype machine was presented to the University management and commissioned on 30th June 2020 by Honorable Sally Mbanefo, who is the Commissioner for Tertiary Education in Anambra State, Nigeria.

 

Picture of the Commissioning of the Prototype Machine.