DFRobot Science Lab Season 2
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EP10: Automatic Plants Fill Light
Introduction
Standards
NGSS
5-PS3-1 Use models to describe that the energy in animals’ food (used for body repair, growth, movement, and to maintain body warmth) was once from the sun.
3-LS3-2 Use evidence to support the explanation that traits can be influenced by the environment.
Science - Grade 3-5
Overview
The shortage of sunlight often slows the plants growth down significantly. In this lesson, students will discuss how to solve the problem of lack of sunlight in a greenhouse in winter or rainy days, and try making an automatic light fill device to help plants grow better!
According to the NGSS standard engineering design requirement in 3-5 grades, the course is divided into 3 parts, they are respectively “DEFINE ENGINEERING PROBLEMS, DEVELOPING POSSIBLE SOLUTIONS, OPTIMIZING THE DESIGN SOLUTION”. Just like engineers, students will find problems, set goals, design plans, build and test models, optimize and improve models, and finally complete the engineering design task.
Activity 1 DEFINE ENGINEERING PROBLEMS
Find Problem
In cold winter, fresh fruits and vegetables cannot grow naturally, and often need to be planted in warm greenhouses. However, the sunshine time in winter is short and there are often cloudy days, plants are hard to grow in such conditions. How to solve this problem? Let's find out a solution together!
In the previous project, we talked about that the point of direct sunlight will change in winter. This is the time of the year when the sun is slanting the strongest, so the light is very weak and the sunshine period is short. In order to solve the problem of lack of light in greenhouse, we can design a device that automatically supplies light for plants, let's try it together!
Engineering Goals
Make an automatic light-supplying device for plants.
Activity 2 DEVELOPING POSSIBLE SOLUTIONS
After determining the engineering goals, let us follow the process of “Brainstorming-Drawing Prototype Diagram-What You Need-What You Do-Test and Evaluate”to develop a solution and complete the building of auto light-supplying device.
Brainstorm
Let’s first brainstorm how to build an automatic light-supplying device. In the process, try drawing a prototype of the automatic light-supplying device.
Raw Prototype Diagram
In the brainstorming, we have initially understood the function and structure of the automatic light-supplying device. Try drawing a prototype diagram. In the production process, the prototype diagram will be an important reference.
What You Need
What You Do
Test and evaluate
After the above steps, a simple automatic light-supplying device is done! Put it next to the plants, when the light sensor detects that the light is weak, it will automatically turn on the LED light to supply light.
Do you think there is still something to be optimized for the device? Can the supplement be achieved manually? For example, by pressing a switch, you can manually turn on the lamp. Try to come up with an optimization plan.
Activity 3 OPTIMIZING THE DESIGN SOLUTION
Let us continue the process of “Brainstorming-Drawing Prototype Diagram -What You Need-What You Do-Test and Evaluate” to carry out optimization and iteration of light-fill device and add manual controlling function.
Brainstorm
What You Need
Based on the above activities, add the following BOSON modules and other materials.
What You Do
Test and evaluate
The optimized device realizes automatic and manual control at the same time. When the light sensor detects that the natural light becomes weak, it will automatically turn on the LED light. When we press the button, we can also manually light up the LED light.
Further Development
In this activity, we made a very simple automatic light-supplying device for plants, and we can also continue to optimize the design of the device. For example, what color of light helps plants grow better? Let’s continue to explore it!
Science Background
Why do plants need light?
As the saying goes, "All living things depend on the sun for their growth”. Most of the energy on the earth comes from the sun. Through its photosynthesis, plants can convert solar energy into chemical energy, which is stored in the formed organic compounds.
Photosynthesis refers to the process by which plants absorb energy from sunlight and convert carbon dioxide and water into oxygen and their chemical energy. In photosynthesis, plants first absorb the energy of the sun, and then use this energy to decompose water molecules into hydrogen and oxygen, and finally oxygen is released into the atmosphere. The hydrogen and carbon dioxide combine to form glucose or plant food, which is stored in leaves, roots or fruits.
The energy produced through photosynthesis not only meets the needs of plants for their growth, but also provides a source of food for humans and animals. In this way, plants are like a giant energy conversion station, converting solar energy into energy that can be used by humans and animals.
What color of light do plants like?
Green plants have the strongest absorption of red light and blue-purple light and can perform photosynthesis best, so plants prefer red and blue-purple light. This is why the fill-in lamps on the market are generally red light and blue-purple light.
Conclusion
In this project, we made an automatic light-supplying device for plants, and solved the problem of lack of light for plants in winter or rainy days. In the further development, we also mentioned the effect of light color on plant growth. Choosing an appropriate color helps optimize the design of the device.
The project is going to an end, please remove cables, and put all the BOSON modules back into the original positions of the kit.
![[Boson for micro:bit] Mind+ and micro: bit 01](https://dfimg.dfrobot.com/5dbaa190f2c4183e48c5a2b7/makelog/03f9dae68bc594a9f63386774fe54ee7_224x164.jpg)
