Indian scientists from the Indian Institute of Technology, Madras, Tamil Nadu have come up with a robot, called- 'HomoSEP' that could save and transform the lives of manual scavengers and help in terminating the inhumane practicing of manual scavenging forever. 

As per census, 2011, around 794,000 cases of manual scavenging were reported across India. The state of Maharashtra topped the chart with a score of 63,173 cases; the other states that followed the list were: Madhya Pradesh, Uttar Pradesh, Tripura and Karnataka. 

Manual scavenging is a term primarily used for carrying/cleaning human excreta or disposals from an open drain or from a septic tank/sewer with the use of hands manually. In the year 2013, the definition and expression of the term 'manual scavenger' expanded. It depicted the persons or the people engaged or employed at the commencement of this Act or anytime thereafter, by any local authority/agency or by a contractor, for manually cleaning/carrying/handling in any manner, human excreta taken from an insanitary latrines/sewer/open drain, disposed to other spaces/premises as notified by the central government or the state government governed under that particular region (manual scavenging/Wikipedia).

In a general practice, these manual scavengers use hand-tools, for instance- buckets, brooms and shovels by which they move human excreta and disposals into baskets, which then is carried by them to the specified locations marked by the local authorities.

This dehumanizing practice of cleaning is very much prevalent in many parts of India and its neighbouring countries. People engaged in this occupation are exposed to deadly substances and gases produced from these human coprolites (faecal matter); they rarely carry any personal protective equipment (PPE) to cover themselves. These PPEs include protective clothing, helmets, goggles, designed to protect wearers' bodies from any kind of harm/injuries- physical, biological, chemical, electrical, heat or infections carried by the air-borne particulate matters.

The robot 'HomoSEP' will be able able to perform all the actions carried by any manual scavenger. It will clean-up the decomposed domestic wastes from the septic tanks. We already have an idea, what kind of toxic wastes/gases are generated inside a septic tank. Methane (CH4), Hydrogen Sulphide(H2S), Carbon-di-oxide(CO2), ammonia(NH3), Nitrogen-di-oxide(NO2) and traces of carbon mono-oxide (CO) etc are the most prominent ones.

These hazardous gases are present in high and low concentrated forms. When present as low concentrates, they can cause irritation in eyes, sore throat, suffocation, coughing, and other breathing problems; whereas, loss of consciousness and eventual death could be the leading consequences of the highly concentrated forms.

Under the supervision of Prabhu Rajagopal and Divanshu Kumar, a team of researchers, prepared and designed a highly sophisticated rotary cutters, which basically functions like the blades present in a homely-run mixer-blender; homogenizing the hard sludge/slurry present within a septic tank. 

These cutters are very sharp and and could enter a narrow manhole in a retracted position, forming an umbrella later. The robots are adjustable and can be integrated with any vehicle that has a power backup and a carriage, for example tractor/earth mover/JCBs etc. The resulting sludge can be transferred to a definite spot for recycling purposes. The slurry can be carried out with the use of a suction pump; can be treated at a water treatment plant.

Such inventions are truly remarkable for the welfare of humankind. 

In the year 2020, a new proposition on the 'Prohibition of the Employment as Manual Scavengers and their Rehabilitation (Amendment) Bill called for a complete mechanization of sewer cleaning, better protection of manual scavengers at work and proper compensation in case of any unfortunate circumstances/accidents.

https://www.nature.com/articles/d44151-022-00063-z

Note: a few lines of the term manual scavenging taken from wikipedia

Image Courtesy: Google (not for commercial purposes, but for a cause)