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Our Team 4 from Vantage College of Applied Science, consists of 5 sub-teams with specified distributed works: Documentation, Electrical, Mechanical, Structural, and User-Interfaces. We applied the engineering design processes for the successful design project of the Energy Recovery Clothes Dryer.

Energy Recovery Clothes Dryer with Music Player Reminding the End of a Cycle

Clothes dryers consume electricity and other sources of non-renewable energy to function. To encourage energy sustainability, our design of dryers are taking the main objective of high efficiency. Other key design objectives of our group’s clothes dryer design are short drying time (max. 1hr), quality of drying performance, reasonable capacity per period (250*220*300mm), and appropriate price range competing for the average market price ($360). The key features of our group’s clothes dryer prototype must include a function of playing music after a successful period of operation. Another essential prototype of our design is a function of Bluetooth connection with phones for setting a specific song from a playlist and getting notifications of the current progress of drying. Also, the dryer must be hazard-free from any safety concerns including flaming, toxic, and others. Considering these objectives, functions, and constraints of the design, reliable and detailed plan and progress of the design are explained in the next pages.

Project Overview

Multidisciplinary Engineering Design Project: Energy Recovery Dryer

Problem Statement: Clothes dryers are powered household appliances used commonly to dry the washed clothes more quickly and successfully than natural evaporation. However, dryers usually use a lot of electricity and other sources of non-renewable energy to function. Moreover, to encourage environmental sustainability, the dryer needs to use a better method to conserve electricity. If the dryer is able to properly function using solar energy or any natural source of energy, this would be very beneficial to the environment. Adopting an expensive non-renewable style might end up backfiring on the environment, as it would even be better to dry clothes on a rack in the sun. Therefore, the main goal of the design of Energy Recovery dryer is to be sustainable with the great energy efficiency.

Design Objective: The key design objectives of our group’s clothes dryer design are short drying time, quality of drying performance, efficient energy consumption, adequate capacity per period, and appropriate price range competing for the average market price ($360).

Constraints: The rules that cannot be violated by this prototype are any drying operation without the user’s command, not exceeding reasonable size to be fitted in a regular household (250*220*300), and safety concerns including flaming, electric shock, and others.

The Electrical and Electronic Design

The main aim of this sub-team is to understand and analyze the principle of the electronic components used for the project. This group seeks to connect the motor, fans, heater, sensor and breadboard together. Because of this, there were interactions with the Documentation Sub-Team to discuss the functions, objectives and constraints, and the Mechanical Sub-Team to discuss the locations in terms of the motor, fans, heater and sensors. In addition to that, a correct Arduino Code was written to operate the project.

Electrical/electronic sub-system



The functions of the electrical components of the Energy Recovery Dryer are as follows:

  1. The electrical components of the Energy Recovery Clothes Dryer must generate enough power to dry the clothes at the set temperatures, whether manual or automatic.


The objectives of the electrical components of the Energy Recovery Dryer are as follows:

  1. To design the prototype of an Energy Recovery Clothes Dryer (EneRec Dryer) by July 14th , 2020; using different software such as Arduino (for the User-Interface, operational and electrical programs). The various electrical components is used, such as diodes, capacitors, resistors, jumping wires, heaters and fans to achieve a goal of short drying time, high quality of drying performance, efficient energy consumption, adequate capacity per period, and appropriate price.


The constraints of the electrical components of the Energy Recovery Dryer are as follows:

  1. Limited maximum voltages.
  2. A limitation of electrical components.


Power Supply - Switches

According to the functions, objectives and constraints proposed by our group, we comprehensively found that the MOSFET is most suitable as a switch for the dryer, as for the reasons will be analyzed in the following article. The MOSFET is a type of field effect transistor with an insulated gate from the channel and the voltage at the gate terminal determines the conductivity. The advantage of this switch is that during the on-state, there should be no limit to the amount of current it can carry. In the off state, the blocking voltage should not have any restrictions and the resistance is infinite and the operating speed of the device is not limited. When the device is turned on, the voltage should drop to be zero.

According to the working characteristics of MOSFET, we also found a suitable voltage for the dryer. Because low threshold type power MOSFET may not switch on until at least 3V or 4V has been applied to its gate and if the output from the logic gate is only +5V logic, it may be insufficient to fully drive the MOSFET into saturation. Using a lower threshold MOSFET designed for switches that have thresholds as low as 1.5V to 2.0V is available, and its maximum value up to 12V.

The voltage we are going to use is 9V, as the dryness quality objective seeks to accomplish. The voltage should be high enough to make the dryer efficient. For the circuit, we choose a DC circuit to power up our electrical parts. There are three reasons that we decided to use DC. Firstly, Direct Current is more stable than Alternative Current, which is more secure for the components used. The objective is to dry clothes in a short period. The voltage of the alternating current will keep changing. The voltage will be from high to low and from low to high. It is a process of changing the voltage, which is not what we expected. However, the AC circuit is less expensive than the DC circuit, which is something to be considered in the choice between them.

Another reason for using DC is that DC is safer than AC. When people touch the circuit, they act as resistance. So, DC is much safer than AC, as in AC the voltage fluctuates. Therefore, the most suitable choice of the dryer is DC.  

Fan circuit

Fan Circuit

The fan circuit consists of the following components:

  1. 9V DC
  2. Capacitor (Ceramic Capacitor)
  3. Resistor (R2 10k resistor)
  4. Diode (D1)
  5. Fans
  6. MOSFET (Gate, Drain, source)
Motor circuit

Drum Motor Circuit

The drum motor circuit consists of the following electrical components:

  1. 5V DC
  2. Arduino Uno
  3. Resistor (10k R3)
  4. Motor
  5. MOSFET (Q1)
  6. Capacitor (C6,C10)
  7. Diode (D1)
Heater circuit

Heater Circuit

The heater circuit consists of the following electrical components:

  1. Heater
  2. Resistor (R1, R6, R7, R8)
  3. Capacitor (C7)
  4. Opto Triac (OK1)
  5. LED2
  6. Triac (T1)

Temperature and Humidity Sensor

The main purpose of the sensor is to detect the temperature and the humidity of the dryer. It is recommended that is the sensor should be placed between the circuit and the drum. Around this setup are the motor, belt and the fans. After discussing with the M sub-team, the decision we made is that the position of the sensor should be between the drum and the circuit. If the temperature and the humidity are appropriate, the system will work. Otherwise, the system will be paused.

Mechanical Design



  1. The motor support should be able to support the motor stable for a long time
  2. The mechanism of the connection between motor and drum needs to have a high drive efficiency to transfer the kinetic energy of the motor to the drum.


  1. The production cost of the motor support should be affordable.
  2. The support should occupy as less space as possible, the inside space of the dryer is limited.
  3. The mechanism of the motor connection is asked to produce noise as little as possible.
  4. The mechanism needs to have a long life-time, low failure rate and low wear rate for components.


  1. The machine size must be at most 250 mm by 220 mm by 300 mm
  2. The capacity of the dryer must be at least 0.5 L
  3. The mass of the support can not be too large.

The Design

Drum Size

Figure 1 - a Gear Mechanism

Because of the constraint of the machine size at most 250 mm * 220 mm * 300 mm, as well as the capacity of at least 0.5 L, we discussed that there could be about three different diameters of drum size in our consideration. One with the diameter of 200mm, another with the diameter of 100mm, and the other with the diameter of 50mm. In terms of the length, 100, 150, and 200mm are in consideration. In order to select the final design, the criteria consist of the cost of the material, the cost of each use, the capacity of the clothes, and the practicality. The Pugh Method is also used.

Table 1. Drum Size (diameter) using Pugh Method
Diameter (mm) 200 100 50
Cost of the material -1 0 1
Cost of each use -1 0 1
Clothes capacity 1 0 -1
Practicality -1 1 -1
SUM -2 1 0
Table 2. Drum Size (length) using Pugh Method
Length (mm) 200 150 100
cost of the material -1 0 1
cost of each use -1 0 1
capacity of the clothes 1 0 -1
practicality -1 1 -1
SUM -2 1 0
Figure 1 of a L-Shape Support for a Motor

According to the Pugh matrix, the too large or too small sizes could lead to the low practicality because the 200mm diameter and 200mm length drum could leave the spare space in use, while the drum with 50mm diameter and 100mm length could also be impractical because of its small capacity. In summary, the drum with 100mm diameter and 150mm length is chosen.

Drive System and Motor Support

The final design (Fig.1) we chose for the drive mechanism is gear, it is the mechanism which is composed of a gear connected to the motor and another gear connected to the back ring of the drum. The drum is rotated by the gear which is carried by the motor. In this design the motor is set away from the drum by means of a continuous belt loop which means the connection between motor and drum is indirect. This can minimize the vibration of the mechanism during operation and other problems which are caused by vibration such as wear, noise, low life-time and so on. This design also has low production cost since the belt is very cheap and the mechanism has simple structure.

Combined Tubes with Heat Insulation materials and fins

The final design we choose for the support of the motor is the “L” shape support (steel). The “L” shape structure of the support provides a better stability and firmness than other types of supports. The steel also makes the support stronger and wight. The support is attached to the motor through two screws in the side of the motor. This simple design also facilitates its production.

Heat Exchanger Top

The final design we choose for the support of the motor is separate tubes. Although this design has a lower heat exchange efficiency, the cost and counter space are better than other designs. Combined tubes with heat insulation material and fins can save a large amount of power to heat the incoming air, but low air passage efficiency and cost are unacceptable. Combined tubes with heat insulation material have similar problems.

Structural Design


Structure of the Water Collection Tray

The requirements for the structural design (the functions, objectives and constraints)


  1. To design a water collection tray.
  2. To design a steel or plastic enclosure
  3. To design a thermal insulating door.
Structure of the Enclosure


  1. The water collection tray is used to collect the water from the clothes when the dryer is working.
  2. The enclosure and the door work together to ensure that the clothes do not fall out when they are drying.


  1. The size of the dryer is within 250×220×300 (mm).
  2. It should contain an LCD display and some navigation buttons for the user interface.
  3. It should have different modes of operation depending on the user's needs.
  4. The temperature must not be too high. Must be below the maximum heat resistance of the material.
  5. Consider the economic costs.
  6. There should not be any safety risks.

The Design

The overall shape is rectangular parallel piped, where the drum is horizontal. The final design has the following advantages:

Using automatic control device.

The drum is made of high-quality stainless steel with high temperature resistance.

The door is fitted with a glass inspection window for easier access to clothes.


Figure 2: Structure of the Latch in the Closed State

The enclosure includes some panels, which are inlaid in different places according to different uses.

Figure 1: Structure of the Latch in the Open State


A latch is a mechanical fastener that fixes the door and front panel. Figure 1 is the closed state, figure 2 is the open state. The movable part is fixed on the door, and the fixed point is fixed on the front panel.


Structure of the Door's Front

The final design of the door is a side-hung door with a door handle. when opening, it will be more labor-saving. The round design is to conform to the shape of the drum. We added a rubber sealing ring on the back of the door to be leak-proof and hermetically sealed.

Structure of the Location of the LCD and Buttons

LCD and buttons & matching openings location

We arranged the corresponding positions on the front panel according to the components that need to be installed. We arranged the components that need to interact with the user above the front panel. We arranged the parts that need to interact with the user above the front panel to facilitate the user to operate.

Water collection tray

Structure of the Door's Back

This designed tray could be pulled out like a drawer. It is placed in the lower-left corner of the front panel. The hollowed-out design in the middle allows fingers to reach in and pull it out easily.

Extra features

We added some additional features to the dryer to complete the drying of clothes.

The first is when designing the door, our extra design is to add a rubber ring on the back of the door to increase the sealing of the dryer.

The second is that we plan to use transparent materials on the front of the water collection drawer, so that in real use scenarios, users can see the actual amount of water collected in the water drawer.

User-Interface Design

The User interface is the manner a user can interact with a machine. Programming facilitates this interaction between the EneRec Dryer (in this case) and the user. In this project, the User Interface sub-team is in charge of some features. The basic features that need to be present into the dryer performance are: the operational program (starting and stopping the machine), the user-interface program (where the user can interact with the EneRec dryer using an LCD and buttons), the LCD and input hardware, and the security system (track the machine status and warn user when the dryer is in abnormal operation). Although the team needs to incorporate these basic features, some additional features may be also included. The user interface of a machine is divided into two parts: Inputs and Outputs of the machine. The Inputs are all the instructions that users give to perform some activity, whereas the Outputs are messages or ways of communication that the machine uses to communicate with the user. In this project, a microcontroller (Arduino Uno) is used to control the dryer.



1. The Energy Recovery Dryer must be able to interact with the user.

2. It must have multiple washing modes (Automatic and Manual modes).

3. The EneRec dryer must completely dry the clothes within 1 hour.

4. Receive signals from the sensors to ensure the door is closed.

5. The dryer may have some added features, in this case:

  • To play music after the drying cycle is done
  • To work interact with the user using a Bluetooth device


1. The EneRec dryer should have a simple User Interface.

2. It should dry in a short amount of time.


1. The size must not exceed 250 x 220 x 300 mm, therefore, large components cannot be added.

2. The power consumption of the entire system should not exceed 12V AC.

3. The EneRec Dryer must use an Alphanumeric Liquid Crystal Display (LCD) and navigation buttons for user interface.

Placement the User Interface components (in color)

The Design

Hardware Layout

The dryer design has 4 buttons, a LCD, a piezo, a LED, and a Bluetooth component. For this design, the two buttons are for selecting the objects as cursors ("up" and "down"), one is used to confirm ("okay"), and the other one is to start the cycle ("start" button). This buttons are located on the front of the dryer which facilitates the user with the machine-user interaction. The LCD is located to the right of the buttons. The piezo and Bluetooth components are located on the inside of the dryer

Operating Sequence and Program Flow Chart


The Energy Recovery dryer has two drying modes for the user to choose, Automatic and Manual. If the Automatic mode is selected, the dryer temperature is set to 30 degrees Celsius, the time is set to 50 minutes and the desired dryness is set to 100%. The Manual mode, as its name present, is the mode where the user can manually adjust the desired time, temperature and dryness. After any of these modes is selected, and the time, temperature and desired dryness are set, the EneRec Dryer will ask the user if the clothes are already inside and if they are ready to start the drying cycle. When the clothes drying cycle is finalized, the EneRec Dryer's LCD or the user's phone, will prompt "The clothes are ready" and a music will play using the piezo.

Virtual and Actual Prototype Demo

The following videos present the Electrical/Electronics and User Interface Arduino's program working.

This video shows the twoo modes available and how do they work. This video also presents the mode selection, and how the EneRec Dryer will work after given values.

The following video is a demonstration of the fan, heater and overall electrical system working.


[1] “Clothes dryer,” Wikipedia, 29-May-2020. [Online]. Available: [Accessed: 09-Jun-2020].

[2] “Electricity usage of a Clothes Dryer,” Electricity usage of a Clothes Dryer - Energy Use Calculator. [Online]. Available: [Accessed: 09-Jun-2020].

[3] A. Holst, “Washing machine ownership 1970-2018,” Statista, 08-May-2020. [Online]. Available: [Accessed: 09-Jun-2020].

[4] P. P. Inc., "Dr. Dry Portable Clothing Dryer 1000W Heater,", 11 June 2019. [Online]. Available: [Accessed 11 June 2019].

[5] “Products,” - Washers & Dryers - Washer & Dryer Prices - The Cost of Washers & Dryers. [Online]. Available: [Accessed: 09-Jun-2020]

Live Chat

We are on duty during capstone hours according to this roster:

Day One: Monday Jul 13th, 2020

Day Two: Tuesday July 14th, 2020Min

Names Day & Time
Ore Adeniyi and Sinung Choi Day 1, 11:15am – 1:00pm
Aurea Gutierrez and Ore Adeniyi Day 1, 1:00 - 2:45pm
Ore Adeniyi and Xiang Ren Day 1, 2:45 - 4:30 pm
Harley Han and Suri Huang Day 1, 4:30 - 6:00 pm
Xiang Ren and Sinung Choi Day 1, 6:00* - 7:45 pm
Minrui Jiang and Aurea Gutierrez Day 2, 8:00 - 9:50am
Aurea Gutierrez and Jiaxiang Li Day 2, 9:50 - 11:40am
Andy Zhang and Yang Wang Day 2, 11:40 - 1:15pm

Chat with us on Collaborate Ultra!

*Team 4 will not be available from 6:00 to 6:30 pm due to the interview and assessment by our professor Dr. Goh

About Us

Usually , in most assignments and projects at Vantage, the students are placed in groups of two, three, four or five. However, for the VANT 151 project, the students in this team were placed into a group of ten. In addition to that, there also smaller sub-teams of two people each who operate in five different areas to make this project function appropriately in every regard. The sub-teams are:

  1. Documentation Sub-Team
  2. Electrical Sub-Team
  3. Mechanical Sub-Team
  4. Structural Sub-Team
  5. User Interface Sub-Team

Documentation Sub-Team

Ore Adeniyi

Ore Adeniyi

Documentation Sub-Team contributor

I am Ore Adeniyi and I am an engineering student at UBC. As a member of the Documentation Sub-Team, I compiled the information to the oral presentation, the website and the report of the project. From the Energy Recovery Dryer project, I learned about the work required in compiling the work of the other students. Also, from these experiences, I am able to learn about various aspects of the project. In addition to that, I learnt about being accountable to other people, as most of the work done is as a team.

Sinung Choi

Sinung Choi

Documentation Sub-Team contributor

My name is Sinung Choi, a documentation sub-team member and a partner of Ore Adeniyi. I contributed to the general documentation of the project (report, presentation, and website) with Ore. I was also in charge of constructing an overall plan or task at a group level by gathering and combining work from our group members from other sub-teams. As a team 4 group member in a multidisciplinary engineering design project, I realized the variety of working and its beauty of collaboration for one successful engineering project. I appreciate the value of the diverse role of each team and team members for their dedication to cooperative technical communication online.

Electrical Sub-Team

Andy Zhang

Andy Zhang

Electrical Sub-Team contributor

I am Andy Zhang, an engineering student from UBC. As an electricla group member, I worked with Yang on the electronics circuit, assembling the components, and designing the prototype of the Energy Recovery Clothes Dryer. I was resonsible of the objectives, constraints, and the functions of the electrical design. Also, I provided a new circuit schematic and description of the motor. During this project completion, I leared how to program using Arduino and how the components (motor, fan and heater) should be connected to the microcontroller. I learned how a clothes dryer mainly work and how some added features may improve the final product. After working with my team, I also learned to listen to the ideas given and how to make them work with the project to successfully achive our alternative design.

Yang Wang

Yang Wang

Electrical Sub-Team Contributor

My name is Yang Wang and I am a student from UBC. As an electrical group member, I mainly work on the circuit schematics, assemble the components and design the prototype of the dryer. After this project, I learned how to use Arduino to operate the motor, fans and heater. I also learned the principle of a clothes dryer. At the same time, it also improved my teamwork ability.

Mechanical Sub-Team

Xiang Ren

Xiang Ren

Mechanical Sub-Team contributor

I am Xiang Ren, an engineering student at UBC. I am part of the Mechanical subteam, where with the help od Minrui, we contributed to design different parts of the EneRec Dryer: the drum size, the motor-drum connection and the motor support. Me and Minrui designed these parts using a CAD software named Solidworks, facilitating the design process. After teamwork, I have learned how to express my ideas in an efficient manner, and to connect my idea with my teammates' to succesfully desing our Energy Recovery Clothes Dryer.

Minrui Jiang

Minrui Jiang

Mechanical Sub-Team contributor

I am Minrui Jiang and I am currently studying engineering at UBC. In Mechanical Sub-Team, I contributed to the design of drum size, motor drum connection and the motor support. I designed these parts using Solidworks, a Computer-Aided Design (CAD) software. This software faciliteted us the design process. In this project, I learned some useful techniques in designing and realize the importance of teamwork and communication.

Structural Sub-Team

Harley Han

Harley Han

Structural Sub-Team contributor

I am Harley Han and I am currently studying at UBC. I am part of the Structural subteam, where I contributed designing the water collection tray, the latch, the door, and some of the additional features of the project. During this project completion, I have learned to work with my team, listenign to all ideas and merging them to meet the requirements. I have also learned how to use Computer-Aided Design (CAD) softwares, Solidworks in this case, to design the structural parts.

Shurui Huang

Suri Huang

Structural Sub-Team contributor

I am Shurui Huang and I currently am studying engineering at UBC. As a member of the Structural Sub-Team, I contributed to the design of the doors, the latch, the water collection tray, and some of the additional features of the project. From this project, I've learned the importance of teamwork and how to work on a certain project by communicating and cooperating with my teammates.

User Interface Sub-Team

Aurea C. Gutierrez Basurto

Aurea Gutierrez Basurto

Team Leader

User Interface contributor

I am Aurea Carmen Gutierrez Basurto and I am currently studying engineering at UBC. As the team leader, I have to help my group in the creation of the Energy Recovery Clothes Dryer. I worked with them discussing the possible features which may be added, took all those ideas given and merge them to successfully meet the requirements. I was in charge of the overall project to be congruent. On the other hand, as an User Interface group member, Jiaxiang and I mainly work on the Operation and User Interface programs to make the dryer efficient and simple to use. During this project, I learned how to lead a team and all the parts that are needed to succeed in a project planning process. I learned how to use Arduino coding and components, how does an LCD work, and how is a clothes dryer programmed to have different features.

Jiaxiang Li

Jiaxiang Li

User Interface contributor

I am Jiaxiang Li and I am a current engineering student at UBC. As an User Interface group member, Aurea and I were in change of the EneRec Clothes Dryer operational and user-interface programs. With this project I learned how to work as a team and how to apply what you have learned flexibly in real product. In addition, network cooperation is a very interesting and novel way to work and study together, and I have learned a lot from this project.