Tsuyoshi Yokoyama

ENGINEERING DESIGN PORTFOLIO

TSUYOSHI YOKOYAMA

Phone Number:

416-834-4323

Email Address:

tsuyoshi.yokoyama@mail.uto

ronto.ca

Home Address:

Suite 3406, 832 Bay Street,

Toronto, ON, M5S 1Z6

Mechanical Engineering Graduate majoring in Solid Mechanics and

Mechatronics Design. Finished university degree with proven high

proficiency on Computer-Aided Design and Finite Element Analysis skills.

Drove the projects focusing on different field includes manufacturing,

electrical design, product design and programming. Earned reputation for

passionately and diligently working in individual and team-oriented

environment, and exceptional working ethic. Enjoy the process of seeking

for real-world engineering challenges, solving problems with creativity and

continuously making headway on the design till satisfaction. Currently

seeking for a job to apply knowledge and passion on practical engineering

design.

Multidisciplinary Project

1.1 Motor Performance Testing Platform & Prediction Tool

Computer-Aided Design Project

2.1 5-axis CNC Milling Machine Design

2.2 Wine Opener Design Improvement

2.3 Self-motivated CAD Projects

Finite Element Analysis Project

3.1 Tensile Members Design

3.2 Conceptual Fluid Dynamics Analyzation

Mechatronic Design Project

4.1 Robot Toy--PLEO rb programming

4.2 Closed-loop Controlled Quadcopter

TABLE OF CONTENTS

Motor Performance Testing Platform & Prediction Tool Objectives:

Our client, BionX tasked us to develop a

prediction tool which can predict the torque and

velocity performance of the BLDC motor that

they are currently developing. In addition to the

prediction tool design, a testing platform needs

to test a motor and verify the result with the

prediction tool. For the prototyping purpose,

the two designs need to produce a reasonable

accuracy within a 5 to 10 percent of error.

Design Features:

The testing platform measures the difference of

force applied by the motor on two ends of belt,

which is proportional to experiencing torque.

Leading Screw connecting to handle is used to

controlled the position of load cells, in other word,

the friction exerted on motor.

Iteratively redesigned the CAD model until feasible

and reliable final design agreed by every team

member.

Sufficient strength of structure is ensured with

ANSYS simulation under 500 N.

Considering low maintenance cost, the key inter-

connecting parts are using standard components.

Implemented microcontroller to collect, process

and display accurate testing result.

Prepared training manual and implementation plan

for future users.

Final Conclusion

Further improvement and expanded function is possible with current design, such as

stronger structure and integrated controller system. However, because of time and

financial constrain, the current design is shown as final design during capstone showcase.

5-Axis CNC Milling Machine Design Objectives:

As a course project, the team is asked to

perform professional engineering design on the

mechanism of CNC milling machine. We

choose to challenge CNC machine with 5-axis

movement includes linear motion in x, y, z axis

and rotation around x and z axis. My

responsibility is to design parts of movement

mechanism with high accuracy and low cost.

Design Features:

For higher accuracy and strength, the linear

motion is relying on leading screw rotation.

The rotation about x and z axis is realized

through belt connecting between motor and

working table.

For working table, we choose 4 jaw chunk as

our working table because it provides

maximum versatility and centering accuracy.

The frame supports the spindle and cutter on

top of the machine and utilized lead screw for

z-axis motion.

Developed final technical blueprints involved

3D & 2D drawings, BOMs and exploded

views.

Final Conclusion

First off, to ensure high centering accuracy,

the innovatively introduced 4-jaw chuck

into the system as a working table. Next,

lightweight materials for example aluminum

alloy was introduced and replaced the

traditional heavy frames made of stainless

steel. Our design further allows workpiece

motions in 5 directions. Finally, from

economic perspective, despite the fact that

candidate design 2 integrated new ideas and

technologies into product design, the cost

was successfully controlled under the

budget.

Wine Opener Design Improvement Objectives:

Our team is aimed to improve existing

mechanism design in the real world. We

choose to optimize butterfly wine opener.

After our research and survey, we defined

complicated operation, difficulty during

the drilling process and unstable wine

bottle stabilization are defined as the main

problem to solve for improvement.

Design Features:

• Downloaded 2D drawing for original wine

opener for and simulated the same model for

better understanding on the design.

• Tried and learnt to model complex features

from YouTube.

• Installed a clamp with rubber cover to

stabilize the bottle as the first step.

• Designed a gear train to turn ‘screwing’ and

‘pulling’ operation into back and force

turning of the level.

• Added an extra handle to make handle turning

much easier.

• Produced engineering blueprints which is

assumed to be ready for manufacture.

Final Conclusion

After adding mechanisms to the existing

design, new design has only one lever,

one clamp and 4 gears to transfer

motion. The 4 gears work in pairs, which

are essential in saving the energy to

screw the worm into the cork as well as

pulling the cork out of the bottle. Based

on data from Internet and calculation,

the existing design requires 88N to pull

the cork out of the bottle, whereas the

new design requires only 63.3N to

complete the removal process. This

saves almost 30% of force.

Steam Engine Vertical Reverse Gear

Wheel Chair Revolver

Self-motivated CAD Projects

Tensile Members Design

Objectives:

Designed and adjust two tensile members

with highest strength-to-weight ratio with

constrained components. Plate in

thickness of 0.25 inch is made of PMMA

and the other one in thickness of 0.0625

inch is made of Aluminum. Cut designed

components with waterjet cutting

machine and connect them together for

testing.

Design Features:

• Choose adhesive for connection

method between two plated for higher

strength and minimized stress

concentration.

• Removed unstressed material and

analyzed these holes with concentrated

mesh iteratively to reach highest

strength-to-weight ratio.

• Create new geometry for hole making

to deconcentrate the stress and remove

larger material at the same time.

• Endeavored to make the holes at two

ends of members, which is constrained

for this project, to stand the largest

tensile stress

Final Conclusion

Test result made large difference from expected value. First of all, aluminum plate experienced

large deformation without yielding on pin point although this was considered to be the biggest

threat during the simulation on ANSYS. In fact, adhesive is the main reason cause the failure.

Portion of adhesive dropped during the first stage of testing, and gave higher stress and pressure on

other portion of the parts. The originally adhesive part was exposed to high load, which is an

unexpected situation without simulation on the ANSYS. According to test result, it was believed

that mass on the aluminum can be further decreased due to its ductility. Besides, the geometry of

PMMA on adhesive area can be redesigned to prevent dropping of adhesive.

Conceptual Fluid Dynamics Analyzation

Objectives:

For this course, perspective to the CFD and

its application to fluid flow and heat transfer

is mainly introduced. In addition, the use of

a popular CFD package: ANSYS Fluent and

application of CFD to practical problems is

what we focusing on during the project, such

as analyzing air flow over wood plate in

certain temperature, or simulating water flow

pathline over a step.

Estimate

Design Features:

• Concentrated mesh around boundary

and steps for high accuracy estimation.

• Compared calculated and simulated

boundary layer.

• Plot velocity and temperature contour

for whole domain.

• Acknowledged the application of

boundary layer thickness and skin-

friction coefficient in industry and

Robot Toy--PLEO rb programming

Objectives:

For the whole course, teammates and I worked on

integrating and programming for the robot to

achieve different goals of contests. The first contest

is to knock down every blocks on the table. The

second one is to walk back and forth on the table

without running into another robot. The third one is

to design the motion to make audience to understand

what mood the robot is expressing.

Design Features:

• For every contest, the team plotted flow

diagram during initial stage of design.

• Analyzed utilities and limitations of different

sensors to reach safe and reliable detection.

• Reduced complexity of code implementation

for the same function but with higher

accuracy and faster response.

• Tested and optimized the code to prevent

possible accidents.

Final Conclusion

For the first contest, we won the 1st place among the

class. And for the later two, preventing detecting error

from the sensor is able to help the team reach higher

score.

Closed-loop Controlled Quadcopter

Objectives:

The initial plan for our design project was to design

a quadcopter which is able to balance itself and

move around according to user input. The

quadcopter was to feature an Arduino UNO

microcontroller as the processing unit and an

accelerometer to detect its Euler angles, most

importantly roll and pitch according to the fact that

a quadcopter will move to the direction it is leaning

into. The balancing and movement of the

quadcopter is based on its current Euler angles and

a desired set of Euler angles, which is calculated

with the command given by the user.

Design Features:

• Utilized and set up the sensors to detect

experiencing Euler angle and 3-axis

acceleration.

• Assembled frame, motors and

• Derived relationship among detected

value from sensors, the current position

of the quadcopter and needed motor

power to reach the desired position.

• Applied PD controller for movement

stabilization.

• Two Bluetooth module are required to

achieve a cheap two-way communication

channel between the drone and the

controller device.

Final Conclusion

Many techniques taught in the course had

been applied such as control loop construction

and code optimization to maximize our

system’s efficiency and response speed.

During various soft tests, we have observed

that the system response is as desired, but

unfortunately we were not able to further tune

it according to the actual behavior of the

quadcopter due to repeated ESC failures. The

team, however, will continue working on it

based on interest and it will work hopefully in

the near future.