South Pointing Chariot

This chariot was first made by a Chinese king who asked his men to build a chariot which always points in the direction of his kingdom, no matter where the chariot went.
And it doesn’t use any compass but differential gears to keep the man in the same direction. It was the first use of differential gears in the world.

Spherical Tetrahedron

The interior angles of these triangles do not add to 180 degrees (like planar triangles). The tetrahedron is formed by joining 6 great circles (circles whose radius is equal to the radius of the sphere).

Triangular Wave car

This car draws triangular wave when it moves!

Triangular wave means that the y-component is proportional to the x-component  (which is the distance traveled by the car).

The y-component is the half circumference of the middle gear and the x-component is the circumference of the car wheel. In our case, both the radii are same.

Thus, the distance traveled in y-direction is half of that in x-direction.

Therefore, the slope of the lines, tan θ = 1/2


Sine Wave Car


This special car draws a sine wave as it moves!

On y-axis, we have the sinθ component of the circle as shown in the upper figure, and on x-axis we have the movement of car which is rθ.

Therefore, the graph would be between (sinθ, rθ) which would be a sine curve.

Everyone has seen the above image of a unit circle, but when we showed this car to engineering students, they were not able to explain why the car draws a sine curve.

Meritorious students from all over Gujarat spend a month and Science City and their project culminated at IIT Gandhinagar

Yesterday, 30 children from science city visited IIT Gandhinagar. Their children are toppers from every district of Gujarat and have been selected to be part of a month-long program organized by Science City to exposure children to have awareness about biodiversity. They had a wonderful time to tinker with lots of low-cost hands-on science and mathematics toys. After the hands-on session, children visited the CLI lab where they got chance to explore various exhibits in detail like the south-pointing chariot, enigma machine, a simple bot based on Chebyshev 4 bar mechanism to name a few. They were also amazed to see the car which makes sine wave and triangular wave when it moves on the floor. The mechanism left the children mesmerized. After having lunch in mess, the children got the visited labs at IITGN and library too. They were really fascinated to see the infrastructures and design of the campus and many of them who aspired to be engineers inquired about the process of getting enrolled in IITGN. We hope that this experience will inspire them to achieve success in future.

Glimpses can be found here: