The Gridfollower is a vehicle that can navigate to a defined point on a grid.

Description

As you can see, most modern logistics centers use autonomous vans to transport goods. In this project we built our own autonomous transporter. The idea was to build and program a vehicle which can navigate to a specific coordinate on a grid.

Technology

Arduino, L298N, TCRT5000


Partners

Benedict Dorndorf

Construction

This Project was About to built and develop a vehicle which can navigate to a specific coordinate on a 6x6 grid.

Video

Sensors

Process

1

At the beginning of the project, we tried to run the two motors of the Gridfollower. The hardest part here was to make them run synchronous because they weren't the best quality and did spin at different speeds even though we put the same amount of voltage on them. We solved this problem by creating an algorithm called PID.

Tha algorithm looks like this:

2

The second task was to make the vehicle follow a line. To solve this task we soldered Five reflective sensors on a circuit board and connected them to the Arduino board. With the reflective sensors, we can check if the vehicle still is on the line or if it has to drive a curve.

To visualize wich reflective sensor is currently on the line we added an LED strip. When one of the five reflective sensors is over the black line the LED on the fitting position lights up. We also have added rubber bands to avoid slipping.

3

After the vehicle can follow a line now we tried to figure out how we can make it navigate on a grid. The vehicle always starts from the left bottom position so we defined two variables in which we put the amount of "steps" it should go in X and Y direction. The gridfollower does a "step" when all five reflective sensors cross a line.

When the vehicle finished his steps in Y direction it does a 90 degrees turn to the right and does his amount of steps in X direction. The 90 degrees turn finishes when the reflective sensor in the middle of the vehicle is over a line again.

To clarify this process I visualized it in an animation: