OVERVIEW
Introducing our innovative camera model, which seamlessly integrates the realms of photography and GPS technology. Its primary function is to streamline the process of identifying specific biosensors and accurately locating their deployment points. This device lets explorers precisely track each biosensor's whereabouts while evaluating lithium availability in these areas.
Our intended market comprises small-scale miners in Ghana who may not own or have limited experience with mobile phones. Its user-friendly design makes this device remarkably straightforward, requiring minimal user experience and expertise. This simplicity sets it apart from smartphones, which can often be more complex to navigate.
Each biosensor before deployment will be attached with a unique barcode. The camera will take an image of this barcode and save it with its GPS location, and that image is saved onto an SD card in the camera.
AI Thinker ESP32 CAM
This microcontroller combines an Espressif ESP32-S MCU chip with an ArduCam OV2640 camera [1]. It has Input / Output pins to which we can connect other peripheral electrical components controlled by the Espressif ESP32-S MCU chip. It needs 5V to operate. This has an inbuilt SD card module onto which we insert the SD card to save the images of barcodes and GPS locations that have been taken.
Adafruit 2.8-inch TFT Touch Shield
This screen was used to preview the images the OV2640 views, so the user is aware of the image they are taking before pressing the button to take the image. It needs 5V to operate.
GY-NEO6MV2 GPS Module
This module provides its location on the earth as latitude and longitude coordinates to the microcontroller it is connected to. It needs a supply voltage between 3.3V to 5V to operate.
ESP32 DOIT DEVKIT
This microcontroller unit (MCU) was added to the camera module because the AI Thinker ESP32 CAM did not have enough pins to accommodate all the peripherals. Hence, it was included to receive data from the button and the GY-NEO6MV2 GPS Module and communicate the data received to the AI Thinker ESP32 CAM. It needs 5V to operate.
Two 3.7V 18650 Lithium-Ion Batteries
This is the primary supply voltage to the entire camera module. The two batteries are connected in series, giving us a total voltage of 7.4 V.
LM2596 DC to DC Buck Converter
The maximum voltage needed by all other components to operate is 5V. However, the primary supply voltage is 7.4 V. Hence, we needed a converter to decrease the supply voltage from 7.4V to 5V. We included the LM2596 DC to DC Buck Converter in our circuit. This regulator has a fixed output voltage of 5V.
Demo of our Electrical Hardware Prototype
After the biosensor has been linked to a GPS and extracted from the ground, the procedure involves users sending both the biosensors and the SD card containing images of the barcodes associated with GPS locations. Once we receive these biosensors, we can remove the hydrogels and group them based on their GPS locations. We capture images of the hydrogels to document any color changes and process this data through specialized software. This software model generates a probability map for lithium distribution across different sections of the surveyed field. This resulting surface plot provides valuable information to our users or consumers, enabling them to pinpoint the exact location within the field suitable for lithium mining. More details on the software model can be found here.
