Designing and Prototyping an LED Plant Grow Light

Project Info

Case:

The client that was a Canadian company working on in-house horticulture designs requested Meee-services for making the design and prototyping of a highly efficient LED plant grow light to be used in a 3-shelf unit for growing of nutrient-rich organic vegetables. Each LED panel was supposed to provide the light for each shelf in a way that all the underneath area was uniformly illuminated at an average of 30 Cms.

Also, the LED panels were requested to be electronically controllable by a control panel to imitate the sunlight spectrum throughout a whole day. The design needed other design specifications including:

  • The maximum dimensions of each panel was 400 x 400 x 10 mm
  • Max 30W power for each panel with V=12V and I= 2.5A

LED

Challenges:

Some of the challenges of this project as requested by the client included the following,

– Using a variety of light spectrum including

  • Violet
  • UV (starting at 280nm)
  • Some red
  • Some white to change the look for aesthetic purposes
  • RGB….

– Using the most efficient combination of light spectrum to best imitate the sunlight
– Choice of quality yet and high long life yet cost-effective LEDs that could provide the given wavelengths
– Using 3W power LEDs
– Considering a proper solution to prevent overheating of each LED panel in the unit
– Software control of each light spectrum color used in the design through a control panel with the following condition

o Control of light intensity at any given time
o Control on LED light on/off

– Each panel was to be controllable individually at any given time
– Completing the project and producing a functional prototype within 4 months
– Finally, the most challenging part was fitting the design to the already designed control panel that was earlier made by the company itself

Solution:

In order to meet the above requirements, the design team made a thorough research on the existing products and technologies aimed at finding the best solution satisfying the followings,

– An electronic design that could meet all the client’s requirements
– The most efficient color configuration for the design
– Finding an LED manufacturer that was capable of making quality customized LEDs according to the given specifications
– Providing the maximum flexibility for changing the color configuration during the test and actual application of the product

Following several weeks of research on the existing products and on the existing power LEDs for such a design, an Arduino based solution using I2C buss communication system was suggested. The Arduino board was fed by two wire SDA (Serial Data Line) and SCL (Serial Clock Line) system that was connected to the control panel.

LED

Also, during the course of the design, and in order to provide a highly uniform light on the underneath bet, the earlier requirement for using 3W power LEDs was replaced by using 64 LEDs with the power of 0.5 for each LED. The higher number of LEDs provided better coherency of light while keeping the power requirement.

The final design was finished after 3 months and after many technical sessions with the company’s product designers to check every detail of the design. After the design, it was applied for the prototyping.
You can see the design and the real prototype in the images.

Description

The final result was quite satisfactory, it included all the requirements requested by the client. Moreover, the first prototype successfully passed all the tests aimed at checking its capabilities for an in-house horticulture product. The in-house growing of cannabis was tested and the growing rate was almost similar to the growth rate under sunshine. To enhance the design and make it more efficient, more studies were scheduled to be made on finding a better light configuration and customized LEDs.

Client:
A. K. Sheppard
Date:
October 24, 2017
Location:
US
Category:
Electrical and Electronic Engineering