Goodbye to manual scavenging? IIT Madras develops robots for task

Researchers at the Indian Institute of Technology, Madras, have developed a robot to clean septic tanks without human intervention.

Named “HomoSEP”, ten units are planned to be deployed across Tamil Nadu and the researchers are in touch with sanitation workers to identify the locations, officials said.

Gujarat and Maharashtra are being considered for the deployment of the robots that have been developed with an aim to eliminate manual scavenging in the next phase, they said.

At present, first two HomoSEP units have been distributed to self-help groups led by Nagamma and Ruth Mary whose husbands died tragically during sanitation work, through the support of the NGO, Safai Karamchari Andolan.

"The septic tank is a poisonous environment, filled with semi-solid and semi-fluid human faecal material that make up about two-thirds of the tank," said Prabhu Rajagopal, professor, department of mechanical engineering, IIT Madras.

"Hundreds of deaths are reported every year across India, due to manual scavenging in septic tanks despite bans and prohibitory orders,” he added.

Rajagopal explained that the HomoSEP can homogenise the hard sludge in septic tanks through custom-developed rotary blade mechanism and pump the tank slurry using an integrated suction mechanism.

“Sanitation workers will be able to operate the HomoSEP on their own, after being provided with relevant training and appropriate guidance along with necessary safety measures, both of which our team is working on right now," he said.

"Safety plays a vital role in this whole procedure, starting with the design of HomoSEP itself,” he added.

HomoSEP was first developed as a final year masters' project by Divanshu Kumar under the guidance of Rajagopal and showcased at the IIT Madras Carbon Zerp Challenge 2019, after receiving seed support from IIT Madras' Socially Relevant Projects initiative.

Despite the pandemic-related difficulties over the next couple of years, the IIT Madras researchers collaborated with an IIT Madras-incubated start-up Solinas Integrity Private Limited (now headed by Kumar) to further develop HomoSEP.

GAIL (India) further supported product development and CapGemini supported efforts towards miniaturisation and portability of the robot, through their CSR initiatives.

Over the last year, NSE Foundation and L&T Technology Services Foundation have commissioned the fabrication and distribution of 8 and 2 numbers of HomoSEP robots respectively, through CSR support.

"The HomoSEP project is unique as it has brought together key stakeholders, including our team, an NGO, industry CSR and a start-up to develop a solution to an urgent and pressing social problem," Rajagopal said.
"No doubt the problem is large and complex, and we hope that our efforts serve as an inspiration for others to join in the push,” he added.

Deepthi Sukumar, national core team member of the SKA said, "SKA, a movement against manual scavenging, has been campaigning for the mechanisation of all sewerage work."

"This is history in the making as Nagamma, a widow of a person who died in a septic tank, becomes the owner and an entrepreneur of mechanised septic tank cleaning services," she said.

"This enterprise will focus on changing lives of sanitation worker communities with dignified livelihoods providing mechanised sanitation solutions to stop manual scavenging deaths and will engage with IIT Madras for their technical expertise and support," she added.