Creative electronics

Conga is a self-stirring cup holder coaster. By placing a cup on the conga and starting to pour in a liquid the conga will start to turn the mug so the liquid will get stirred.
There is a pressure sensor mounted to the bottom of conga, this is used to determine when the mug should start spinning. A spoon can be placed in the mug and with the help of a magnet in the conga, the spoon should stay in place.

Hardware & Software

The frame of the Conga is made from laser cut MDF, the top of the frame is a freely rotating disc that is attached to a small dc motor. On the bottom of the Conga is a pressure sensor that measures the weight of the Conga and what is placed on top.
Inside the Conga are an Arduino and a motor driver.
The Arduino reeds an Analog value from the pressure sensor and determines based on a threshold if the motor should start spinning.


It turned out that the dc-motor that we picked was not strong enough to turn the disc if a mug was placed on top of the Conga. When it did spin, there was no good way of controlling the speed. This problem could be fixed by using a continuous rotation servo instead of the dc motor. This way we would be able to control the speed, and the servo should have enough power to rotate a mug.
We never had a good chance to test if the spoon would actually stay in place, the answer is probably no. The spoon would need to be designed so it would stay in place if the mug started turning.

Course reflection

At the beginning of the course, we had different partners. I only did the first assignment with my previous partner, and he wasn't even there. When I found out my new partner I was very confident the collaboration would be fine. My goals for the course were to get a better understanding of electrical components, and how to use them. Through the lectures and the practical assignments, I got to know a lot of components and also understand how to use them in practical situations. When doing the practical assignments we had a nice flow, and always finished on time, even if we had some difficulty with a certain part of the assignment. We usually prepared the assignment beforehand, this helped a lot, but also led to some extra challenges during the first practical assignment in the report where we had put together a lot of resistors to get the desired resistance values. It was nice to get some hands-on experience with electronics and learn about different electrical components and their function. I can say that I achieved my goal for the course, and I hope we can show that in the mini project. I think Bart and I were a good team, and we worked well together.

Conga was created for the course ‘Creative Electronics’ by Peter Peters at the Eindhoven University of Technology. Creative electronics is one of the basic courses for first-year Industrial Design students.

In collaboration with Bart Bolluijt.