CE432 Robotics II   Fall 2021
Tutorial 3: ESP32-CAM
Humberto Arredondo
harredondoperez@fortlewis.com

Using ESP32-CAM

1.- Introduction
In this tutorial the students were assigned to do more challenging tasks using the ESP32-CAM module and its video options using the Web Server. Also, they were able to paired up a sensor to measure altitude, temperature and presure.

The equipment and materials used for this tutorial was: 2.- Methods and Results



Task 1

For this task, a code for streaming video in a Web Server was loaded to the ESP32-CAM module and It was found in Rui's textbook. After loading the code and copying the IP address i the browser, an image of the web Browser can be seen below in Figure 1 . This also worked in a cellphone (Figure
2).


Figure 1. Image shows myself while working on this video streaming.




Figure 2. Screenshot of the streaming video working on a cellphone.


Task 2

For this task, A webserver was used to displayed Temperature, Pressure and Altitude. This data was obtained by a BMP180 Sensor. In order to make this possible, the librarys of ESPAsyncWebServer and the AsyncTCP  were installed in the Arduino  IDE.  Code from Rui's book was used for this tasks, but some changes needed to be done. After adding the WiFi credentials to the code, the IP address was obtained from the Serial Monitor and copied to the browser. In Figure 3, these measurements can be seen. In Figure 4, the altitude of Durango, Colorado obtained from Google can be observe, and compare to the value was obtaing by the sensor.



Figure 3. Web Server is displaying the video streaming, Temperature, Altitude and Pressure.




Figure 4. Durango, Colorado's altitude obtaing from Google.


Task 3

In this task, the ESP32-CAM was used to added to a remote controlled car robot with a camera that was able to be controlled from a Web Server. In the Web Server 5 different functianlity buttons were made (Forward, Backward,Left, Rigth and Stop). This robot car has 3 batteries that provided a total of 11.1V that power up directly the L298N motor driver and also a voltage regulator that reduces the voltage to 5V that powers the ESP32-CAM module. After some soldering and changes to the code provided from Rui's textbook, the front view of the finalized product can be seen in Figure 5, below. The side view can be seen on Figure 6. On Figure 7, a short video of the car functioning using the commands on the Web Server is shown.



Figure 5. Kit car front view.



Figure 6. Robot car side view.



 Figure 7. Robot car demostration of the final product functioning.

After we confirmed that everything is working properly, we designed a PCB for the robot car in EAGLE. Creating a PCB is a great way to clean up the project and help with cable management. The schematic and layout of the PCB is show below.


Figure 8. Schematic of the PCB.

The schematic showed in Figure 8 contains an ESP32-CAM module, pins for the motor driver, two power connections, a three pin connector for programming reasons and a jumper for when code replacement is needed.



Figure 9. Layout of PCB.

The layout in this PCB showed in Figure 9 shows the final look of the PCB it self. The hole in the bottom is there for a L-bracket that will hold the PCB to the chasis of the Robot Car.



Figure 10. Robot car with PCB installed final view (missing the antenna).

In Figure 10 the antenna was not capture at te time the picture was taking. we can see the functioning Robot Car with the PCB in Figure 11.



Figure 11. Final Product.

Discussion:

This robot car tutorial was the most exciting one because the students were able to do hands on assembling this car kit and, modified the code provided to make it work. The students discover a handful of new applications for this module. In this process were a lot of issues such as module's Wi-Fi misfunctioning, code for wheels troubleshooting, faulty camera and rotating the image 90 degrees. The PCB was designed and replaced successfully, and all the components needed were soldered. Making the holes in the car's chassis was challenging because the material is brittle. We can see in Figure 10 how the car is missing some pieces.