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Project Development Planning

Please see open the tabs to see the specific actions that each section demands and the percentage of the action achieved.


Time Table

Mounting

Motor Control

Sensor Control

Electronics

Electronics Programming

User Interface



Week 1: Concept Development


In this week we did some general sketches.


Relevant Questions:

  • Tape over the wall surface, we want to reduce friction while keeping tightness for the optics.


Week 2: Cad Design


For this week I designed a fusion model for smart trap that I am building. Some of the questions. I have are:


  • Impact of depth of focus and angled camera, will ortho-rectification be necessary?
  • Optical magnification or higher resolution, necessary?



Week 3: Sticky Tape Roll


This week I looked for potential rolls of sticky tape. Some of the characteristics that we were looking for were:

  • small i.e. less than 20 cm in width and not to heavy as this will require a bigger motor.
  • have glue only on one side so it is easy to unroll, they typically have glue on both sides.
  • ideally be yellow.

Luckily, I discovered a roll of sticky tape from a crop protection equipment supplier based in Spain. The roll is very small and contains up-to 6 meters of sticky tape, and has a length of 10.5 cm and a width of 4.81 cm. The price was about 5.86 euros per roll. It was the only roll that had a waxy layer on one side of the tape. The color is not yellow is blue which is supposed to attract thrips.

Thrips source: Wikipedia
Thrips source: Wikipedia


A point to make is that the tape is semi translucent and you can see patches of glue which might not be ideal for object detection it might be necessary to place it against a white background.


Week 4: Camera and Connection


During this week of embedded electronics, I tested the microntroller XIAO ESP32 S3 sense. This microcontroller has a camera and wifi capabilities which is perfect for my device. I tried to make it work both in C++ and micro python. Thereafter, I tried to send pictures through WiFi to my computer but this is still a work in progress.



Relevant Questions: Processing of the pictures for object detection (applying weights) and image processing should be done on the micro-controller or in the computer. That’s is the difference between sending a picture or a vector with counts.

Week 5: Bearing Holder


This week I printed some holders for holing the bearings that will help facilitate the rotation of the sticky trap roll. I printed the piece in white PLA filament.



Week 6: Electronic Components


The peripherals I will be using for my project are:

  • DHT22 sensor

with following electrical specifications:

  • 3.5-5.5 VDC
  • Operating current 0.3mA and 60uA (standby)
  • PW,GND and data pins
  • Price aprox 1 dollar.

and

  • a DC motor,with following electrical specifications:

  • 12VDC

  • Current@ Max Efficiency (RPM): 120

  • Current @ Max. Efficiency (mA) 74

  • Price: 10.95 US$


Motor Data Sheet

In order to work with the motor we need to have a larger power source that the XIAO ESP32S3 can handle. At least a 9V battery or higher. Ideally, we can utilize this battery to power also the ESP32 therefore, we will need also a module to reduce the power from 9 or 12V to 5 volts. In addition we will need to get a half h bridge driver to operate the motors

I watched a video on how to use motor drivers

https://www.youtube.com/watch?v=NIx_KycgOJM

I looked at different videos and found this particularly useful. From the table in this video we can see that the TB6612FNG is in the range of voltage that we need is not expensive and has very low current standby mode.

https://www.youtube.com/watch?v=PVyAcgYkzDs


We can find the pin out for this half bridge below from electropeak:



I found that the following site has a robot car project where the electronic requirements are quite similar to mine, I think I could apply their circuit schematics.


Dronebot workshop project

Here I have tried to replicated using Kicad.

Week 9: Input devices


For this I week I tested the temperature and relative humidity sensor I outlined in week 6.


I as well built a mdf case for mounting the camera for testing



Testing of the camera indicated that the light is very low, and the angle view (66 deg) was not sufficient to cover a good portion of the sticky tape.



I ordered a new camera that has a larger field view (120 deg.)


I also cut a acrylic roof to allow more light in which I still need to test.


Week 10: Output devices

For this week I fabricated a PCB board for my bridge.

and I also tested the bridge and the motor using a 9V battery that feeds the motor and the Xiao controller using a voltage reductor.

I also designed and 3D printed an axis to mount the Sticky Tape roll.

Finally, I tested the system to assess if the DC motor was strong enough to roll the tape.



The motor and the motor-tape axis works well.


Week 11: Networking and Communications


For this week I wrote some scripts to transfer images and files between a server and two clients.


I also milled a board that will be used for the Xiao Server. This board is also connected to SD card reader that will be useful in storing the data from camera traps.



I was able to send images and text files between two Xiaos.





There were some problems in sending pictures between the Xiao server and my computer specifically I could transfer an entire picture.


Week 13: Molding and Casting

For this week, I wanted to design some buttons in silicone that will have the objective of covering buttons used to mount and unmount the roll of tape into the trap.

I designed the buttons in fusion

And then I milled a block of wax

poured the silicon

and here you can see the result.



Week 14: Interphase Development


The objective was to develop a user interface that could:

  • Connect to the Xiao server to retrieve stored data from the Xiao Smart Trap,
  • Display the images captured by the trap and
  • Visualize the recorded temperature data.


The final dashboard interface based on R’s Shiny framework is shown below:


R: Shiny

Week 15: Project Integration

PCBs

For the project, I will use a total of three PCBs. The first PCB will house the Xiao microcontroller and provide connections for the DHT11 sensor, motor driver, and control buttons. Additionally, this board will be connected to an LED to ensure consistent lighting for image capture.

Motor bridge

the motor bridge controls the motor responsible for advancing or replacing the sticky tape. Both components are connected to the main PCB, ensuring coordinated functionality within the system.

Button board

The button board is used to manually control the tape mechanism—rolling the tape when a new roll is installed in the system and unrolling it when the tape is fully used, allowing for easy removal and replacement. Aside from manual operation, the tape is also rolled forward automatically on a weekly schedule.

MCU board

The MCU board will serve as both the server and the main controller for the camera trap sensor, handling some data processing and communication.

In the server it will have connections to:

In the camera trap, the system will be connected to the following components:

Communications

In the past, I encountered significant communication issues between the Xiaos. To resolve this, I integrated antennas, ensuring they are properly connected to the MCUs for better performance.

Energy source

The Smart Trap will be powered by a battery, which will drive the motors. To reduce the voltage for the Xiao, a step-down converter, the DM0014X8, will be used.

Week 16, Wildcard week image detection


Case

The cases for both the server and the camera trap will be 3D printed.



Schedule


BOM(ongoing)