• Raspberry Pi 3 Model an AI weed killer using sunlight and Raspberry Pi as key components is intriguing, but specific details are unavailable. Understanding how these elements could be integrated into an AI-based weed control system is essential.
  • This is one of those YouTube videos that spread like wildfire across Pi Towers, which is exactly what we hope will not happen as a result of this initiative or any others like it. Do not create one of these, let it roam the area, and then set your entire region on fire. That is not what we want to happen. If you are considering creating fire using the actual Sun’s energy, please exercise extreme caution. We want you to think there’s a lot that may go wrong in this situation. Be careful.

Parts list:

1. Raspberry Pi 3 Model B+ (Robot requires low processing power, suitable for any board):

The final revision of our third-generation single-board computer1.4GHz 64-bit quad-core processor, dual-band wireless LAN, Bluetooth 4.2/BLE, faster Ethernet, and Power-over-Ethernet support (with separate PoE HAT).

The Raspberry Pi 3 Model B+ is the final revision in the Raspberry Pi 3 range.

  • Broadcom BCM2837B0, Cortex-A53 (ARMv8) 64-bit SoC @ 1.4GHz
  • 2.4GHz and 5GHz IEEE 802.11.b/g/n/ac wireless LAN, Bluetooth 4.2, BLE
  • Gigabit Ethernet over USB 2.0 (maximum throughput 300 Mbps)
  • Extended 40-pin GPIO header
  • Full-size HDMI®
  • 4 USB 2.0 ports
  • CSI camera port for connecting a Raspberry Pi camera
  • DSI display port for connecting a Raspberry Pi touchscreen display
  • 4-pole stereo output and composite video port
  • Micro SD port for loading your operating system and storing data
  • 5V/2.5A DC power input
    1. Power-over-Ethernet (PoE) support (requires separate PoE HAT)

2. Fresnel lens (aka giant magnifying glass PLEASE BE CAREFUL):

A Fresnel lens is a form of lens that has concentric rings or ridges on its surface as opposed to being a solid piece of glass or plastic and is frequently referred to as a large magnifying glass. The lens can be significantly thinner and lighter than conventional lenses while still having the same optical qualities because to its distinctive design.

  1. Design: After their creator, Augustin-Jean Fresnel, Fresnel lenses are named. They usually have several thin concentric grooves or ridges on one or both sides and are flat. These grooves serve to concentrate and deflect light, giving the lens optical effects that are comparable to those of standard lenses.
  2. Focusing capabilities: Fresnel lenses have the ability to focus light by bending and refocusing it towards a particular point or focal length. They are frequently referred to as “giant magnifying glasses” because of this characteristic. A Fresnel lens may concentrate sunlight onto a small region to provide enhanced heat or illumination when sunlight passes through it.
  3. Applications: Fresnel lenses are essential in various applications, including solar energy, optics, lighting, visual aids, and photography and cinematography. They concentrate sunlight on small areas, increase energy production, and are found in solar cookers, furnaces, and power plants. They also control and focus light beams in stage lighting, projection systems, and traffic signals, contributing to efficient light distribution. Fresnel lens elements enhance focusing capabilities and performance in photography and cinematography.

3. Cytron motors to move the lens and lift the lid

Cytron motors are utilized in various applications, such as moving lenses and lifting lids, by Cytron Technologies, a company specializing in electronic components and motor control systems.

  • Motor Types:

Cytron provides a variety of motor types that are appropriate for various applications. DC motors and stepper motors and servo motors are a few common motor types for lens movement and lid raising.

  • DC (Direct Current) Motors:

For applications that call for continuous rotation, DC (Direct Current) motors are frequently employed. They are renowned for being straightforward and simple to use. DC motors can be used to power pulleys or gears, enabling the exact movement of lifting devices or lenses.

  • Stepper motors:

In applications that call for precise positioning, stepper motors are frequently utilized. They have remarkable control over rotation angles and move in distinct phases. When precise lens movement or lid raising is necessary, stepper motors are frequently selected.

  • Servo motors:

It’s a compact, precise angular position controller used in applications requiring accuracy, stability, and feedback control. They are suitable for lens movement and lid lifting, ensuring precise positioning.

  • Motor Control Systems:

Cytron offers motor control systems for seamless integration, enabling precise speed, direction, position sensing, and feedback control for lens movement and lid lifting.

  • Applications:

Cytron motors are utilized in various industries for lens movement and lid lifting, including camera systems, robotics, and industrial automation. They enable autofocus, zoom, lens adjustment, and lid opening/closing in camera lenses while controlling lens position and lid lifting in manufacturing processes.

4. Photoresistors to track the sun:

  • Working Principle:

Photoresistors adjust their resistance in response to the amount of light that strikes their surface. They are constructed of a semiconductor substance that grows more conducive to rising light levels. A photoresistor’s resistance increases in the absence of light and reduces when exposed to it.

  • Sun Tracking, Analog Output, Sun Tracking Mechanisms:

Photoresistors detect sunlight direction by measuring intensity. By placing multiple photoresistors in an array, an electronic circuit can compare resistance values and determine the sun’s position. Analog outputs can be processed by microcontrollers to calculate the sun’s position. Sun-tracking mechanisms involve photoresistors connected to motors or actuators that adjust solar panels, mirrors, or other light-tracking devices. By continuously monitoring resistance values, the system can accurately position solar panels or mirrors to face the sun, maximizing sunlight capture.

  • Applications:

By continuously lining up panels with the position of the sun, photoresistors in solar energy systems, such as photovoltaic panels and concentrators, increase efficiency and energy output.

5. Old phone charger for power

  • Older phone chargers with USB connectors offer low-voltage DC output compatible with various devices.
  • Old phone chargers offer 5-10 watts (5V, 1-2A) power for smartphones, tablets, and Bluetooth speakers.
  • “It is crucial to ensure that the voltage and current output of an old phone charger match the device’s requirements to avoid damage or safety risks. Additionally, before use, inspect the charger for visible damage or frayed wires. Furthermore, the USB connector allows for compatibility with a wide range of devices, making it convenient to use an old phone charger with various gadgets. Moreover, the compact size of phone chargers makes them portable, which is ideal for traveling or in locations without wall sockets.”
  • Old phone chargers may not be suitable for high-power devices like laptops or power-hungry appliances due to limited power output and insufficient power for larger devices with higher voltage or current levels.

How does it work?

  • The Raspberry Pi camera is mounted on the bottom of the robot rig. The robot takes aerial photos of the landscape as it traverses the garden.
  • The robot learned to distinguish between weeds and plants that Nathan wants to retain thanks to a TensorFlow custom image classification model. Additionally, the motors flip out the enormous lens when the Raspberry Pi detects a weed and move it into position right over the unfortunate plant. Moreover, photoresistors keep track of the light’s source and supply the data required to focus the sun’s beam via the lens. Furthermore, the plant then perishes in a fire. However, sounds gloomy, yet nature is harsh because it must be.
  • The lens is approximately moved into place by two motors. Subsequently, the sun is then precisely focused on top of the weed by three more motors. Additionally, in order to prevent grass and other plants from being burned while the robot is moving, the large lens has a cover that only lifts when it is in the proper position. Consequently, there is a lot happening right now.

Fresnel lighthouse lenses

  • Nathan describes how this build cleverly reuses a Fresnel lens. One would typically be in use atop a lighthouse. When used for what it was designed to do, it positions itself in front of a strong light source and concentrates the light into a precise beam. Moreover, Fresnel lenses accomplish this while requiring less material than a traditional lens and can have a generally flat form. Furthermore, this powerful, focused beam can be seen farther away by ship crews, making it simpler to avoid the treacherous rocks that support the lighthouse.
  • Similar to how it is employed in other weed-killing projects, the flat Fresnel lens concentrates sunlight on a point approximately two feet beneath it. In this application, the light source must be concentrated into a single powerful beam in the same manner, even though it does not need to go very far to alert vessels that are miles away.

Alternative weed killing

Although we really want to complete this project, we have to admit that we won’t be able to use it to its full potential on our sometimes cloud-covered island. However, we’ll have to keep using Shake ‘n Vac-style chemicals to treat the truly weedy areas of the garden. Furthermore, we’ll then use our bare hands to remove them from flower beds.

AI algorithms

AI algorithms analyse images, detect plant species, and identify weeds, enabling intelligent weed killers to target weeds efficiently.

Weed elimination mechanisms:

AI systems utilize targeted spraying, precision cutting, or other weed control methods to eliminate weeds.

You can check our blogs like- Overview of Infographic, Chandrayaan 3, Overview of Podcast and many more.

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An inventive method of weed control is the use of a Raspberry Pi and sunlight in an AI weed killer. Moreover, the AI weed killer can concentrate and direct energy onto specific weeds, efficiently destroying them, by utilizing the power of sunshine. Additionally, the system’s use of the versatile and small Raspberry Pi computer enables complex control, analysis, and decision-making procedures. Furthermore, this pairing of the Raspberry Pi with sunlight demonstrates how cutting-edge technology has the ability to transform conventional agriculture practices and drive the development of more effective and sustainable weed control techniques.