Course:VANT151/2023/Capstone/APSC/Team4

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Welcome

Welcome to the wiki page of VANT 151 team 4. We are nine first-year students in Vantage Applied Sciences from the University of British Columbia. We implemented a project to design and build a scaled-down prototype of an energy-recovery laundry dryer (EneRec Dryer). This page documents our design process and the final design details of the prototype.

Introduction

In 2018, the British Columbia government developed and implemented energy efficiency policies and regulations to support the province's energy, economic, and greenhouse gas reduction priorities. The government has established two energy goals for British Columbia: accelerating efforts to decarbonize BC and encouraging British Columbians to choose greener products^[1]. Drying clothes is an essential household chore, and the dryer also plays a vital role. However, traditional clothes dryers consume much energy, leading to high electricity bills and increased greenhouse gas emissions.

To design and fabricate the components and assemble a scaled-down prototype of an energy-recovery clothes dryer for drying a cotton handkerchief. By July 10, 2023, use University-provided components and tools to maximize the heat transfer from the hot air and steam exiting the dryer to the air entering the dryer.

This project allows us to have a deeper understanding of the meaning of sustainable development and let us learn how to use the corresponding knowledge to realize the recycling of product energy, thereby reducing the impact of human activities on the environment. The program runs for eight weeks, from May 18, 2023, to July 10, 2023. We subdivided the 9-member team into five sub-teams: Document, Electrical, Mechanical, Structural, and User-interface. Among them, except for the Document sub-team, composed of one person, the rest are composed of two members. In the following sections, we describe each sub-teams work content, process, and results in detail. The Gantt chart in the appendix to this page shows all our teams' timelines and work plans. Short biographies of members are in the last section.

Team Requirements

Problem Statement

The guiding statement indicating the issue this design aims to address:

A significant problem with some standard dryers on the market is that they consume a lot of energy. These dryers work by continuously heating the fresh air, turning the gas into hot air, and letting it out after only one-time use. It not only wastes a lot of energy but also harms the environment.

Functions

Overall, the prototype should be able to:

adjust the drying time and temperature using an Alphanumeric LCD display and navigation buttons.
put clothes in or take them out of the drum.
heat the clothes fully by rotating the drum.
heat the fresh air and remove the stale air out.
dry clothes by converting electricity to thermal energy.

Objectives

General Goals to be achieved as much as possible:

High drying efficiency.
Low gas emissions.
Accurate temperature selection.
Effective heat transfer between the intake and stale air.
Good sealing during the machine during the working.
Low whole prototype weight.
Low operation noise.

Constraints

The prototype shall:

have an external structure not larger than 250 mm x 220 mm x 300 mm, and thus all the components can be placed inside of the external structure;
have at least 0.5 L capacity drum;
not allows electrical power consumption larger than 24 V AC and 40 VA;
be able to dry a cotton handkerchief with size 15 cm x 15 cm (± 3 cm) in less than 1 hour;
have automatic operating mode;
have manual operating mode to be able to set drying time, temperature, and dryness;
be able to complete it in 8 week time.

Electrical / Electronic design

Figure 1: connection of the whole circuit without sensor.

The electronic and electrical sub-team (EE team) is in charge of all electronic circuits, including but not limited to motors, fans, heaters, power sources, and sensors, as well as the EneRec system associated with automatic and manual Arduino programs. Figure 1 is the connection of the whole circuit except the sensor.

Requirements

Functions

The functions of the electrical/electronic sub-system are:

A DHT22 sensor measures the temperature and humidity of a cotton handkerchief.
Using a heater to dry the cotton handkerchief in a safe temperature drum.
Setting manual or automatic mode based on dry time, temperature and dryness.
Making heat cycle and heat flow by fan.
Receiving and input commands and information through the Arduino board.

Objectives

The objectives of the electrical and electronic sub-systems are:

High efficiency heat of flow and heat circulation.
The components in circuit have a low power consumption.
Accurate temperature in drum to avoid cotton handkerchief damage.
Cost-effective and cost saving.

Constraints

The constrains of the electrical and electronic sub-systems are:

using of 24V AC, 40 VA power supply.
Different size of sensor cause DHT22 cannot fit the hole at back of the drum.
DC in motor and fan, AC in Heater.

Main Components

Table 1: Components in the circuit.
Components Name	Specification of Components
Motor	Hobby Gearmotor Yellow, 4.5 V DC
Fan	20 AWG 2 core wire
Temperature/humidity sensor	DHT 22, 5V
Microcontroller	Arduino Uno R3 ATMEGA328
Heater	/

The components in Table 1 are provided by the professor, and these devices all work closely with the EneRec Dryer.

The Design

Power Supply

Figure 2: Convert AC to DC.

The maximum voltage in this design is 24 VAC. Except the heater requires 12 VAC, the other components use DC power supply; therefore, a bridge rectifier circuit was used to build the AC to DC conversion part. Because the Arduino Uno requires 9 VDC, a voltage regulator and capacitors were used drop the 12 VDC to 9 VDC and insure the power supply maintaining at that level. The AC to DC conversion part has been show below as Figure 2.

Fan Circuit

Figure 8: flow chart of fan

The purpose of the fan circuit is to control the airflow in the drying machine. The fan circuit requires 9 VDC (from the AC to DC conversion), A fan, a resistor (10k), a capacitor (0.1 u, > 50V), a MOSFET (IRLB8721), and a diode (1A, 50 ns, UF4004). To use Arduino to controlled the fan speed, the MOSFET is required to connect to the arduino board (Pin 9). Figure 3 shows the fan circuit.

Figure 3: The fan circuit

Drum Motor Circuit

The purpose of the drum motor circuit is to control the rolling of the drum in the circuit via controlling the rotations of gears on both the motor and drum. A motor, a resistor (10k), capacitors (0.1u, 220u), a diode (1A, 50ns, UF4004), a MOSFET (IRLB8721), and a 5VDC power supply are required in this circuit. To use Arduino to controlled the rotation of the drum, the MOSFET is required to connect to the arduino board (Pin 10). Figure 4 shows the motor circuit.

Figure 9: flow chart of motor

Table 2, Alternatives of rotation design
	Weight	Single rotation	Variable rotation
Effectiveness	40	50	30
Stability	30	30	20
Contact Surface	30	20	50
Score	100	33	28

Figure 4: The motor circuit

Temperature and Humidity Sensor

Figure 10: flow chart of heater

The purpose of using the temperature and humidity sensor is to determine whether the cloth has been dried properly by testing the temperature and humidity inside the drum. In this sensor circuit, a temperature and humidity sensor (DHT 11) and a capacitor (50 V, 10 µF). The temperature and humidity sensor circuit requires 5 VDC power supply, and its data pin connects to pin 2 of the arduino board to transmit temperature and humidity have been tested. Figure 5 shows the sensor circuit.

Table 3 Alternative Design of Temperature Program
	Weight (%)	Certain value (%)	Certain range (%)	Certain time (%)
Energy/Component Consumption	30	35	30	25
Response Time	20	35	15	25
Duration	10	20	15	15
Practicability	40	10	35	30
Total Score	100	23.5	32	26

In table 3, the process of designing the Temperature program, different angles of temperature control were considered. The first was to stop the circuit when the temperature was above 35 degrees Celsius. The second is to stop the circuit when the temperature is between 30 and 40 degrees Celsius, when the temperature is above 35 degrees Celsius, and to keep the program running when the temperature is above 30 degrees Celsius and below 35 degrees Celsius. The third way is to set a definite time during which the dryer will continue to work until the time is completed. By using four different indicators (energy, component consumption, response time, duration and practicability) with different weights, it was concluded that the most suitable method for us was a certain range.

Figure 5: The sensor circuit

Figure 7: Flow chart of the Electrical programming

Heat Circuit

The purpose of the heater circuit is to heat the air which been blowed into the drum. This system requires a heater, resistors (10k, 39, 270, 150), a capacitor (10 n), an Opto Triac, a LED, a Triac, and a 12VAC power supply. Pin 8 of the arduino board is used to connect the heater circuit and control the temperature of the heater. Figure 6 shows the heater circuit.

Figure 6: The Heater Circuit

Control Programs

The circuit is controlled by Arduino board. The purpose of the Arduino board is to control the heater, motor, sensor, and fan in the circuit via the code programme. First check the room temperature. When the room temperature meets the criteria, the motor, fan and heater are switched on in sequence. If, during the working of the part, the humidity is detected to be greater than the temperature at which the dryer is drying, the components of the dryer will automatically stop. Figure 4 shows the flow chart of arduino board.

Extra Feature

Door Locking system

Figure 11: the flow chart of buzzer programming

Door locking system is operated by mounting the limit switch with the door. When the door is opened, the limit switch will also open and the Arduino board will receive a signal from the limit switch. This causes the components in the circuit to stop working.

Table 3. Alternative design of Switch
	Weight (%)	Limit Switch (%)	Button(%)	Inductance Switch (%)	Photodiode (%)
Practicability	30	35	30	25	10
Stability	30	35	35	25	10
Installation Difficulty	20	15	15	15	20
Cost	15	15	15	20	10
Total Score	100	30.5	25.5	21.75	12.75

In table 3, we have four different ideas for Alternative designs of switches. The first and second are the limit switch and button provided by the teacher, both of which work by turning the circuit on via a button and allowing the Arduino to detect it. The third method is the inductance switch, which works by allowing current to flow normally through the wire; opening the switch causes the magnetic field to collapse, keeping the bulb lit until the field collapses[2].

Figure 12: the switch circuit

Buzzer

The buzzer is designed to alert the user with an alarm or music when the device is finished running or when the device is interrupted.

Figure 13: the buzzer circuit

Final Design

Figure 14: final design 1

Figure 15: final design 2

Electrical&Electronic sub-system performance results

Figure 16: ENERGY CONSUMPTION

After 30 minutes of dryer rotation, 0.023kwh was consumed.

Figure 17: Test Result

Recommendation

During the programming process, the Arduino Editor can be used to test the input and output data from components, and bugs in programs can be avoided by doing that. During the circuital building process, using the multimeter to test the power supply for each electric components can minimize the circuit problem.

Mechanical Design

The mechanical sub-team designed the Drum Size, Drive System and Motor Support, Heat Exchanger and Temperature and Humidity Sensor based on objectives, functions and constraints.

Requirements:

Functions:

1. Drum can rotate which can accomodate clothes and dry them.

2. Drum can be drived by a motor.

3. Lint can be blocked from getting into the copper pipies by filter

Objectives

1. Maximize the contact area of clothes with hot air in the drum.

2. Minimize transmission losses between mechanical elements, and maximize the rotation efficiency.

3. Minimizes the loss of hot air during operation.

Constraints:

1. The minimum capacity of dryer is 0.5L

2. The transmission ratio between motor and drum must about 1:2.

3. The Drum needs a minimum of 360degree/second rotation speed.

Drum Drive Mechanism Design

The msot important mechanical part of the dryer is the drum itself and the transmissions relationship between the motor and the drum. In order to achieve the motor to durm power transimiss efficiently, many transmisssion mechods were considered. Figure 1 and 2 shows two types of power transimision that we considered. Figure 1 demostrate the Spur gears option, and the figure 2 shows the helical gears option. For determine whic drive we finally use, we compared the pros and cons of the two options.

Figure 1: Spur gears option

Figure 2: Helical gears option

Comparing between different transmission methods
Idea	Advantages	Disadvantages	Final decision
Spur gears	Simple manufacturing (No support need) Negligible lateral forces Enought power for Drum drive	Noisy Not the best choose for high power transimission	Yes
Helical gears	High transmission efficiency less noisy	Hard to produce (Unignored support affect transmissions capacity)	No

We finally decided to use spur gears as our drive structure. We believe that transimission efficiency along does not determine our choice, but rather we need to choose the option that is better suited to our needs. For the case of 3D printing, compared helical gears, spur gears do not have very outstanding points, but the smaller need for load and transmission accuracy makes spur gears more suitable for our projects.

Drum Size

The drum size is about 500 cubic centimeters.

Drum Drive Components

Power Transmission:

We decided to arrange two spur gears on the motor and drum. The ratio of the small and large gears is 20 : 48, which meets the minimum 1 : 2 ratio required in the constrain. The motor drives the large gear on the drum by turning the small gear.

Figure 3: Small gear and big gear

Motor and motor support:

Because of the large size of the large and small gears, the available space left for the motor is greatliy reduced. Finally, after taking measurements, we decideed to place the motor at a specific angle. Our designed the motor support to hold the motor firmly and stably at a 25 degree angel to the y-axis.

Figure 4: Motor and motor support

Figure 5: Motor and Drum

Drum and Bearing:

In order to reduce the friction generated by the drum rotation, we decided to build a bearing. Bearing can reduce friction resistance, reduce the power consumption, improve the starting performance[3]. Compared to spherical bearing, rollor bearing are mroe suitbale for 3D printing.

Figure 6: Drum Drive

Figure 7: Rollor Demonstration

Heat Exchanger

Figure 8: Heat Exchanger

A heat exchanger is a system used to transfer heat between a source and a working fluid. Heat exchangers can be used for both cooling and heating processes. A heat exchanger is used in a dryer model to ensure the correct temperature within the model.The heat exchange system is a combination of air ducts, transparent tubes, copper tubes, and sleeves. The hot and cold air will be exchanged through the air duct, and the copper tube will transfer the hot air to the tray (shown in Figure 3).

Temperature and Humidity Sensor

The placement of the temperature and humidity sensors is crucial for their proper operation. Due to the high temperature in the area around the heater and its potential impact on the sensor's ability to measure temperature, the sensor should be placed far from the heater. To determine whether the airflow to the dryer is normal, the sensor should measure the temperature and humidity of the warm, humid air entering the heat exchanger. In our group's original design, it was inserted in the U-turn (Figure 5.1). However, the fact that the data is correct for the whole group is a more important case, according to the table below. After that, the sensor was put on the back of the air duct, as the blue part in Figures 5.2 and 5.3 shows.


Ideas	Pros	Cons	Final Choice
Inserted in The U-turn	Humidity measurement is not affected by water vapor	Incorrect position leads to incorrect temperature data	No
The Back of The Air Duct	Sensor measures temperature and humidity uniformly	May be exposed to water vapor	Yes

Figure 9.2: Front Side of Sensor

Figure 9.1: Initial Position of Sensor

Figure 9.3: Back Side of Sensor

Recommendations:

1.The design should not be overly idealized and problems may occur during installation.

2. If separate 3D printed parts need to remain relatively stationary, it is best to design removeable attachment units.

3. The gear density ont eh motor canbe reduced and the high weight of the gear increase the load on the motor.

Mechnical sub-system performance results

Test:

Result:

Structure Design

Requirements:

The structural team is required to work on the enclosure, opening/holes, door & latch, tray, seals/insulation design. The enclosure consists of all parts and elements including openings and their doors and the placements of holes on the panels. The dimensions of all holes and doors are presented in the Solidworks.

Objectives:

The objective of structure sub-teams is to design the enclosure of the clothes dryer (including door opening, tray) with safety and convenient features:

1. The door can be closed easily.

2. The tray can be taken out from the holes easily.

3. The positions of opengins and holes are accurate.

4.The panels can cover whole dryers.

Functions:

The functions are designing the overall framework for the clothes dryer which includes:

1. The door to ensure the clothes do not fall out.

2. The hangers on the door to ensure the door can be opened easily.

3. The tray can collect the water when the dryer is working.

4. The lock can ensure the door cannot be opened while the dryer is working.

5. User interface is making sure the user can order the function of dryers.

Constraints:

The design is constrained by the dimension of Al frames. The position of all the holes are constrained by the dimensions and requirements of other elements including motor & fan, heater, sensor:

1. Size of the EneRec Dryer: 250 x 220 x 300 mm.

2. The temperature of water in the tray cannot be too high.

3. The all materials can be used are provided by the lab.

4. Door must be lcoked while the dryer is working.

5. The dyers must stop working while door is opened.

6. The material of frame must be aluminum.

Enclosure

Figure 1: The Aluminum frame of dryer

The enclosure of the dryer is constructed by the aluminum frame. The frame is used to fix the front wall, side wall and top wall.

Generating Sketch

The following sketch shows the feature of doors:

1.Door Sketch:

Option 1: Round door

Figure 2.1: Round door front view

Figure 2.2: Round door side view

Figure 2.3: Round door whole view

Option 2: Square door

Figure 2.4: Square door front view

Figure 2.5: Square door side view

Figure 2.6: Square door whole view

2.Latch Sketch

Figure 2.7: Snap-fit latch

Option1: Snap-fit

Snap-fit latch is the most common kind of latch in our life, and it is the easiest one to make. To use snap-fit latch, we just need to push the key part into the lock, they are easy to lock because of the slide oblique sides, and once it's locked, it will be impossible to open by pulling parts away. To open it, we need to pull one side of the lock away from the key. An obvious disadvantage of this kind of latch is that 3D printing plastic does not have the flexibility that this latch requires.

Figure 2.8: Cross lock

Option 2: Cross lock

Cross lock is also common and usually applied in washrooms and old houses. This latch is combined with at least two holes and a middle slide bar. Also, there is a small handle on the side of the bar. As shown in figure 2.8, when we try to open or close the latch, we need to rotate the small handle to go through the gap in the second lock hole. This kind of lock is easy to operate, and wear and tear of material is much lesser compared to option 1. However, the only trouble is that there are too many parts we need to screw on, and there might not be enough space on the door for the latch to located on, therefore we did not choose this option in the end.

Figure 2.9: Double-slides lock

Option 3: Double-slides latch

Double-slides lock is commonly seen in family dryers, and it is usually connected to electrical circuits. It is easy to open and close, by just pulling and pushing. Due to its high convenience, double-slides latch is the option we finally choose to use. To build our own double-slides lock, we used 3D printing to print out the lock cover, and used metal sheet to make the lock by bending. Another obvious advantage of this kind of lock is that it doesn't need too much space.

The only hard part for this lock is that we need to bend sheet metal by our own instead of using 3D printing, because the material of 3D printing is rigid, not so flexible compared to sheet metal.

In figure 2.9, the yellow part of the lock will be insert in and will stuck above the yellow part of the lock cover.

Evaluation

The door we designed is downward-opened, and there are several reasons. First, opening downward can make customers easier to put clothes into the laundry machine, and they do not have to worry about dropping cleaned clothes on the ground because the door will be like a plate. Second, this kind of door would not block the view inside the machine. Also, as we know, sometimes sided-opened doors would block the way of customers, and it is hard for users to either see the inside or put in clothes and do further operations. As for the shape we chose when designing the door, we first thought about a round door, but we discovered there wouldn't be enough space for the latch and the hinge if we designed it that way. Therefore, we decided to choose the rectangular (160mm x 160 mm) bottom-shaped door.

Evaluation for Shape of the Door
	Safety (%)	Space for Screws and Lock (%)	Convenience (%)	Durability (%)	Total score (%)
weight (%)	20	50	15	15	-
round door	70	20	40	70	40.5
square door	30	80	60	30	59.5

Therefore, we decided to choose square door instead of round door, mainly because square door provides more space for other parts such as screw holes for hinges and handle, and the space for lock.

Evaluation for Opening Directions of the Door
	Convenience for Space (%)	Convenience for Opening (%)	Protecting Clothes from Dropping (%)	Durability (%)	Total score (%)
weight (%)	20	20	25	35	-
open side	35	70	20	65	48.75
open down	65	30	80	35	51.25

In the end, by evaluation, we decided to choose the door opened downwards, because it can better protect clothes from dropping to the ground and it would not block the side space for users to put clothes in the dryer.

Designs

1.Door

Figure 3.1: front board design

Figure 3.2: door holes design

2.Latch

The latches are designed to lock the door while the dryer is operating and prevent any leakage. We first thought about snap-fit locks for the decision of latches, but we wanted it to be more convenient to open and close. Therefore, we chose a double-slide latch. In addition, this kind of latch can be applied as an extra feature: when the customers open the door, the circuit will be cut off, and the machine will stop working immediately. The insde of the latch is designed with a cambered shape for the purpose that it can lock the key firmly.

Figure 3.3: bottom view of the lock hole

Figure 3.4: front view of the lock hole

Figure 3.5: Lock sketch and its screw holes

As shown in figure 5.4.3, the location of one of the screw hole if movable, the purpose of that is to make the lock flexible, so that the door can be easier opened and closed, also, it can make the latch locking more tight.

3. Location of the control Panel

The location of control Panel is chosen by considering the convenience for users to use. In this case, the control panel is selected to put on the top of the dryer's panel, which is capable for the users to operate and visible. And easy for users to operate. Figure 3.6 illustrates the holes for the LCD and buttons.

Figure 3.6: top board

4. Holes of Water tray standard Design

The tray is designed with the dimensions of 84.5×40×25 mm. The dimension is calculated by considering the maximum holes that can chisel on the side panel. The shape of design is trying to make sure that the tray can be easily taken out from the hole. Figure 3.7 represents the design of hole for inserting the tray and the small holes uses for vending.

Figure 3.7: right side board

5. Handle

Figure 3.8: handle design

Test and Results

Following pictures are the final product for door and latch:

Figure 4.1: whole view of the door

Figure 4.2: top view of the door

Figure 4.3: close view of the lock

Recommendation

During the design and operating process of the door and latch, our team reflected ourselves and found out that we could still improve our design in some aspects. First, the lock design should be improved. During the process of making the key using metal sheet, we made a lot of mistakes and broke most of them due to the durability of the material, aluminum sheet is too fragile. On the other hand, the friction between the key and the latch is bigger than what we expected. In addition, our front board touched the roller when we did the final test. Therefore, We should: 1, Use more stable metal to make the key or use 3D printing; 2, try to make the measurement of the key and lock more accurate in solid works so that it can be smoother; 3, communicate better with other teams and measure more accurate about the size of the boards and frames.

User-Interface Design

Requirements

The user-interface sub-team is required to work on the operation of the UI program, LCD connections and button connections. The operation of the UI program includes starting, stopping drying the clothes and the menu design. The user interface program is required to read the buttons and display the LCD.

Functions

The functions of the User-Interface sub-system are:

1. Two drying modes: Manu and Auto

2. Remaining time display

3. Two drying operations for Auto mode: Temperature and Dryness

4. Time and temperature control in manu mode

Objectives

The objectives of the User-Interface sub-system should be:

1. Functions focus of the clothes dryer that users need

2. Menu design focus including system convenience, operating simplification, and various functions

Constraints

The constraints of the User-Interface sub-system must be:

1. Limitation of LCD screen size (4×20)

2. Maximum drying time is 200 minutes

3. The number of operations of the automatic mode button is controlled within 10 times, and the manual mode operation is controlled within 20 times.

The Design

Design alternatives for menu structure:

Menu Structure design 1

Menu Structure design 2

Menu structure design 3


	Convenience	Protect Clothes	Degree of Freedom	Total
Weight	25%	50%	25%
Option 1	5	3	2	3.75
Option 2	4	5	4	4.5
Option 3	2	5	5	4.25

In the first option, the menu of automatic mode does not allow the user to set the temperature and target humidity during drying. This reduces some of the operations but does not take into account the fact that the default values do not cover the appropriate temperature and humidity range for all fabrics and may cause damage to the fabric. In second option, the automatic mode has some quick questions to reduce this problem, and the manual mode gives the user greater freedom of operation to set the temperature and time of dryer operation at will. In the third choice, the manual mode covers more motor speed and fan speed than the other modes. Although this improves the user's freedom of operation, it makes the process of operation more tedious. And, because the mechanical group has added a paddle to the drum, the purpose of the drum turning over the clothes has been achieved, so it actually makes little sense to change the speed of the motor and drum.

Design alternatives for Buttons:

Button Design Sketch1

Button Design Sketch2

Button Design Sketch3

Button Design Sketch 4

Final Design for Button Design:

Final design has three buttons as its inputs. These three buttons help users to efficiently navigate through the menu options provided on the LCD and enter options and information. The top button is "BACK" for clearing all selections and returning the device to its initial state, the middle button is "OK" for confirming the selection, and the bottom button is "NEXT" for switching options.

The reasons for choosing this design for this project are:

- 2-3 listed options on the menu (Up to three options in the menu options in one page, only need push Next to switch options and push OK to confirm the option)

- Quick maintenance and cost savings

- Operation simplification and low operating threshold

- Small oprating area (Buttons are at the same side of LCD, button distances are small)

Through the Buttons Design Score Table shown below, the Final Sketch has 4.4 point in total which is obveiously the best choice.

Buttons Design Score
	Convenience	Low Maintenance Fee	Button Area	Function	Total
Weight	50%	20%	20%	10%
Sketch 1	3	2	2	5	2.8
Sketch 2	4	3	3	4	3.6
Sketch 3	4	3	3	4	3.6
Sketch 4	5	4	4	3	4.4

Final Sketch

Final Buttons Design

UI design including LCD and 3 buttons

Hardware Layout

1. Buttons

The design has three buttons as its input: Back, OK, and Next respectively. Reasons why three buttons are used is because we want to simplify the operation and use fewer wires.

2. Main Menu Page

Two options are provided: Manu(Manual) and Auto:

(1) Auto: The first option is temperature, users can choose high temp, middle temp or low temp; the last option in auto is dryness, users can choose more dry, normal dry or less dry.

(2) Manu: Manual mode does not provide set options; it provides more accurate settings for users. First is temperature, users can hold the next button or back button to set the specific temperature. As same as the time, users can set the specific time and dryness.

Temperature and Humidity Sensor

The dryer will automatically detect the temperature and humidity of the clothes periodically, and the system will determine the state of the clothes and adjust the working status of the equipment according to the detection results.

Operating Sequence

On the main page, the users are prompted to choose the mode between Auto mode and Manual mode.

Press the "NEXT" button to switch options, press "OK" to confirm the selection and go to the next page. Press "BACK" to reset everything.

(1) Auto Mode: Users are provided with preset options for temperature and dryness (Auto and Manu modes use the same picture).

The first option is temperature, and users can select from high temperature, middle temperature, or low temperature.

The next option is dryness, where users can choose from more dry, normal dry, or less dry settings. This mode offers convenience by providing predefined settings for different laundry loads.

Then the LCD panel shows "Drying". the dryer will stop automatically when the humidity decreases to the present value.

(2) Manual Mode: Users have more control and can set the parameters more accurately.

The first setting is temperature, and users can adjust it by pressing the next button to reach the desired temperature.

Similarly, users can set the specific time for the cycle by using the same button. This mode allows users to customize the temperature and time according to their specific requirements.

And at the end , users can enter their desired humidity level and the dryer will make corrective adjustments to the data they provide.

Then the LCD panel display the time remain.

When the dryer is running, if the user presses OK to pause the system. Press OK again to resume work, or press Back to cancel the task.

When the dryer is running, if the user opens the door, the system will suspend operation and issue an alarm. Close the door to continue working, and press back to cancel this task.

Compare our menu design with others'
Menu	Advantages	Disadvantages
Our	Simple, easy to understand, easy to operate, low maintenance fee	Long processing time
Others	Various functions may attract buyers	Long processing time, complicate functions, gimmick function, high maintenance fee

Program Flowchart

User-interface Sub-System Performance Results

LCD menu structure final result

Final Buttons Design

Extra Feature

Components	Purpose	Objective
Buzzer	Notice users that the drying process is finished	Buzzer makes a sound
Door status detection	Protect users when they open the door when drying clothes	Stop drying when door is opened

Buzzer and Door Detection Flow Chart

Recommendations:

1. Being creative and try to come up with various alternatives and choose the best one, not just use one idea at first.

2. Less is more, more buttons with more functions could become a gimmick and menu with more options could be confused.

3. The flow chart is a very important draft when programming, it helps you to clarify your thinking and find logical errors.

4. After you finish the program, ask your teammates to help you test it, as theory and application often diverge.

Conclusion

In conclusion, our energy recovery clothes dryer encompasses advancements in documentary, electrical, structural, mechanical, and user interface aspects. By significantly reducing energy consumption, optimizing heat transfer, and enhancing user convenience, this dryer represents a substantial step forward in the pursuit of energy-efficient appliances. Its potential for widespread adoption holds great promise for mitigating environmental impact, conserving energy resources, and promoting a greener and more sustainable future.

From a documentary perspective, our energy recovery clothes dryer offers a promising solution by incorporating advanced energy recovery technologies. This innovation significantly reduces energy consumption compared to conventional dryers, thereby addressing the environmental impact associated with excessive energy usage.

On the electrical front, our dryer demonstrates remarkable efficiency by optimizing power consumption through intelligent control systems. The integration of energy recovery mechanisms allows for the reuse of heat generated during the drying process, minimizing energy wastage and promoting sustainable energy management.

Structurally, our energy recovery clothes dryer has been designed with careful consideration of thermal insulation and heat transfer mechanisms. By implementing efficient insulation materials and optimizing airflow patterns, heat loss is minimized, leading to improved energy recovery and enhanced overall performance.

Mechanically, our dryer prototype is engineered to maximize energy recovery while maintaining the essential features and performance standards of conventional dryers. Through innovative heat exchanger designs and advanced airflow management, we ensure optimal heat transfer and drying efficiency, resulting in reduced energy consumption and shorter drying times.

Additionally, the user interface of our energy recovery clothes dryer has been designed with user convenience in mind. We have incorporated intuitive controls, informative displays, and automated features to enhance usability and provide users with a seamless and effortless drying experience. By empowering users to make energy-conscious decisions and easily monitor the dryer's energy-saving capabilities, we promote a sustainable mindset and encourage responsible energy consumption.

Figure: Dryer

Appendices

Gantt Chart

The gannt chart one is the plan of each team in this project, The gannt chart two is the daily work ratio of each team member.

Gantt Chart 1

Gantt Chart 2

Gantt Chart PDF File:G4 Gantt Chart.pdf

PDF Drawing

Assembly drawing (1): File:EneRec Dryer (outside).pdf

Assembly drawing (2): File:EneRec Dryer (Inside).pdf

Part Drawing 1 (Drum Drive): File:Drum Drive.pdf

Part Drawing 2 (Motor support): File:Motor support.pdf

Renders

Render is a photo of the details of the dryer. It allows the audience to better understand each part or combination of the dryer.

Arduino Code

File:Code of UI and EE.pdf

Sustainability

Since we specified the use of 3D printing this time, in the future we will design our dryers using more sustainable materials.

Reference

[1] "Policy, Regulations and Bylaws - Province of British Columbia," Government of British Columbia. [Online]. Available: https://www2.gov.bc.ca/gov/content/industry/electricity-alternative-energy/energy-efficiency-conservation/policy-regulations. [Accessed: 13 June 2023].

[2]“Photodiode - Symbol, Working and Types - Diode,” www.physics-and-radio-electronics.com. https://www.physics-and-radio-electronics.com/electronic-devices-and-circuits/semiconductor-diodes/photodiodesymboltypes.html#:~:text=%EE%80%80Photodiode%20symbol%EE%80%81.%20The%20%EE%80%80symbol%EE%80%81%20of%20%EE%80%80photodiode%EE%80%81%20is%20similar (accessed Jun. 28, 2023).

[3] YB Components, “Understanding the different types of bearings and their advantages - YB components - UK,” YB Components, https://ybcomponents.co.uk/understanding-the-different-types-of-bearings-and-their-advantages/ (accessed Jun. 28, 2023).

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About us

We are international students from 9 different provinces and cities in China. We are good friends in private and good teammates at work. In the team, we cooperated tacitly, helped each other, and finally completed the invention of EneRec Dryer.

Sub-teams:

Document
Jiaming Han Jiaming Han Document sub-team member I am an international student from Wenzhou City, Zhejiang Province, China. I'm an engineering student interested in web design, article writing, and the science side. Throughout the project, I contributed to designing the website and Gantt charts for the whole team, assembling drawings, and providing photo view 360 rendering pictures. Also, I am very interested in mechanical engineering, and I helped them when they needed it. I am proud of the Gantt chart and web design for this project.
Electrical
Haoyang Guan Haoyang Guan Electrical sub-team member and team leader I am an International student from Henan Province in China, committed to being a good engineer. I work with the team member on the circuitry of the entire project and the corresponding code program, and I also help other group members solve their related problems. I really enjoyed the discussions and research with my teammates.	Boby Wang Boby Wang Electrical sub-team member I am an international student from Taizhou, Zhejiang Province, China. I am interested in robots and programming. Through this Drying Machine Project, I contribute to the electoral and electronic parts with their grogram. I have learned the theory of electronic components and the programming of temperature and humidity sensor.
Mechanical
Haozheng Wang Haozheng Wang Mechanical sub-team member I am an international student from Hebei Province in China. My dream is to become a successful engineer. I like to work with my group members and enjoy the process of communication and cooperation. I also enjoy thinking about the mechanics.	Yaoruo Wang Yaoruo Wang Mechanical sub-team member My name is Yaoruo Wang and I am a international student from Jiangsu Province. I am a group member of Mechanical sub-team and working for the part of heat exchanger. Such as the top of heat exchanger and the position of sensor. The work was challenging for me because I had never been exposed to modeling before.
Structural
Yifan Wang Yifan Wang Structural sub-team member I am Yifan Wang, an international student from Hubei Province in China. I am working in the strucutre-sub team in the design of dryer. Although I am not familiar with strucutural design, I have tried my best to cooperate with other group members and think of ideas of design. Moreover, I usually searched on the internet of lock design which is an extra feature in the design of the dryer and I am enjoy to provide ideas and communicate with other groups member.	Tianyi Li Tianyi Li Structural sub-team member I am Tianyi Li, from China. I like running and drawing. I am a member of the structural team in the course VANT 151. I contributed to the stretch of the door and latch design, measuring the open holes of the enclosure, participating in modeling the latch, door, and enclosure in Solidworks, and I made the lock using the metal sheet.
User-Interface
Yichen Li Yichen Li User Interface sub-team member I am an international student from Jiangsu Province in China, my aspiration is to become an Integrated Engineer. In my current position on the UI sub-team, I focus on leveraging my programming skills, which happen to be one of my strengths. Recognizing that the user interface serves as the bridge between users and devices, I am deeply committed to enhancing user experience and bringing greater freedom and convenience to the users of the operating system. Moreover, during my free time, I enjoy providing technical assistance to other groups, be it aiding in mechanical bearing design or assisting with electrical circuit connections. Through these activities, I continue to refine my skills while contributing to the overall success of the projects.	Yuji Chen Yuji Chen User Interface sub-team member I am an international student from Zhejiang Province in China, I have always wanted to be an excellent engineer to let everyone enjoy the fun of technology. I am in User-interface sub-team, working on the entire UI program and relevant hardware layout and design. I also communicate with structural sub-team to deal with their related problems. I really enjoy being in this big group, and designing the LCD menu is my favourite part in this project.