There have been several instances and a multitude of records showing manual scavenging, an activity of taking out waste with the help of the human workforce, a lethal crime. Although the perilous activity has been banned in India since 1993, 620 death cases have been reported in sewage cleaning, according to the latest report released by the Social Justice and Empowerment Ministry, as many as 88 cases were recorded in the past three years alone. According to a 2018 report by the National Commission for Safai Karamcharis (NCSK), one person loses his life in every five days while cleaning sewers and septic tanks across the country.

The Trepidation: Rising problems

India has around 8,00,000 sewage cleaners who come from lower-income groups and are propelled to get down into the sewer lines at the cost of their lives.

These unskilled labourers are forced to get down in the filth without any safety gears, getting exposed to poisonous gases.

There are two types of lines - septic and sewer. Every sewer line gets wider as it reaches close to a treatment plant or big sewer tanks. "Sewer lines is not the main area of concern but septic tanks, as people mostly die while cleaning septic tanks," mentioned prof IIT-Madras professor Dr. Prabhu Rajagopal.

Generally, household, business parks, public toilets, etc are connected with septic tanks. Since these are not cleaned regularly, a lot of mud accumulates into the lines and people have to get down to clear the passage of waste.

What is the solution to manual scavenging?

Professor Dr. Prabhu Rajagopal, from the Centre for Non-Destructive Evaluation at IIT-Madras has invented an electronically-powered, remote-controlled robot, which can be sent down in the septic lines for the purpose of cleaning.

The unique machine is named as Sepoy Septic Tank Robot, has 360-degree motion arm technology which helps in homogenisation of the tank.

"Our goal is to prevent human entry into septic tanks. It is a question of the life of the human beings entering into the tanks which contain hazardous gases and harmful microbes. Our current Robot and future additions are aimed at achieving an integrated solution such that no human entry will be required to access, clean and maintain Septic Tanks," says Dr Prabhu Rajagopal, IIT Madras professor.

About Sepoy Septic Tank Robot

It is a robot which works with the help of a camera installed in it.

The operator can see the condition of a septic line on a screen outside while regulating the machine.

The Sepoy Septic Tank Robot uses high-velocity cutters to cut through the thick sludge in the septic tank.

The machine does not require much maintenance.

"We aim to produce intrinsically safe, a spark-proof machine with very minimalistic maintenance, easy cleaning, modality," prof Rajagopal said.

The mechanism

The cleaning is proposed to be done in two phases.

In the first phase, a mechanical operated and externally powered, intrinsically safe cutter system is inserted to perform an initial homogenization.

In the second phase, the robot is inserted after pumping out some of the contents and filling the tank with water.

The future plan

The team of the Centre for Non-Destructive Evaluation at IIT-Madras has been connected with the Safai Karamchari Andolan, an NGO, and aims to get in touch with the related ministries and Municipal Corporation Departments.

"We are applying for sanitation ministry grants. We took part in a project last year, but because of elections the process has gone slow," he said.

The robots are expected to hit the market in a year or two. The lab trial for the project has been done, "we need to do extensive field trial and mock-up trial which depend upon the support we receive. We are looking for commercial partners," he added.

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