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Project Development Planning


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 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.



BOM(ongoing)