I always wanted to build a robot to address which could create a real practical and social impact. The natural choice was to develop something in the lines of construction, since I am working architect who happened to love robotics.
Being from India, I knew the problem of sanitation has always been there, and there were a few universities who were already tackling this issue with their research projects in 3d printing and deposition of concrete.
Initially I thought along the same lines and thought of developing my own concrete printer. I even did the BOM for a small toilet booth. Then it striked to me as why the implementation of 3d printing concrete might not have been feasible. The cost of concrete along with additives used was too high for something which needs to be created on a tight budget.
Then while creating another BOM for a client which needed me to state how many bricks and cement and sand would it require for his project, the idea hit me. Why not create a robot that automates the most common building method known to man - using brick and mortar.
It made sense. One can find bricks almost anywhere and the mortar mix needed to join them can be prepared without any hassle. I recalculated the building costs involved to build a toilet booth and it came out to be much less than the concrete printer (almost half).
I started building the prototype in 1:10 scale at my local makerspace.