21.06.2021

7th-year students assemble a cart with a battery-powered electric motor

By Bruna Cronfli and Matheus Alves

Based on the knowledge previously acquired in Design Lab classes about pulleys and sheaves, the 7th-grade students (Y7) researched examples of objects that used such concepts. So, to apply the notions of strength and speed learned, they were challenged to assemble an electric motor cart, in which the chassis should consist of nine ice cream sticks.

The students had the autonomy to diagram and project the position of the sticks how they believed to be the most coherent. However, they should not only consider the positioning of the ice cream sticks. They also had to think about where to place the cart’s axles, reflecting on the possibility of the axle turning when glued directly to the chassis or whether it would be necessary to create a kind of pillow block to guarantee the operation of that axle. The entire preparation for using the parts (such as wheels, which had to be drilled to fit the axle) was done by the students under the teacher’s supervision. By connecting the motor to the shaft, the students could also conclude how the transformation of electrical energy into kinetic energy takes place.

The entire project was made from experimentation, trial and failures, which fed the learning process. The teacher did not deliver the results. In this way, students are encouraged to understand in practice how to build a functional cart. In addition, the project is considered to be of great complexity, requires experimentation, and depends on the applicability of knowledge acquired in other disciplines to guarantee the perfect functioning of the cart.

The idea is that when the 7th-grade (Y7) students move on to the next grade, they can use homemade photovoltaic panels, which they will learn to make in the 8th grade (Y8), to replace the energy source of their electric carts.