HKU Robocon 2020

Host department: Department of Industrial and Manufacturing Systems Engineering

Supervisor: Dr. H.H. Cheung (Department of Industrial and Manufacturing Systems Engineering)

Background of the project

The annual Robocon competition project allows HKU engineering students from different disciplines to design and fabricate innovative robots with an integration of various advanced technologies, including IoT sensors, AI, computer vision, and mobile computing. Besides, it provides hands-on experiences on product design, prototyping, CNC machining, design and fabrication of electric circuit and PCB, control program development, etc.

Furthermore, senior members mentor junior members in each year and hence valuable experiences, knowledge, and skills for design and fabrication of robots can be sustained for next year competition. In addition, it enables the HKU students to exchange their knowledge and skills with students from local and other countries’ universities. Therefore, it motivates the students to engage in experiential learning via exploring and integrating various advanced technologies. As a result, students’ innovation and teamwork abilities would be enhanced.

Project details and process

Our team was basically preparing four robots for the Robocon 2020 local context. Our robot development stage was basically divided into 3 stages.

1. Prototyping (September & October 2019)

Develop different approaches and proof-of-concept prototypes for passing, trying and kicking rugby

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2. Design stage (November 2019 to March 2020)

Mechanical design and programming

3. Final Adjustment (April to August 2020)

Fine-tuning and extensive testing of the four robots

Each team was required to complete 3 rounds of flying during 2nd and 3rd day: No payload in 1st round while a payload weighted up to a maximum value of 2kg and 4kg in the 2nd and 3rd round respectively. Our teams completed all the tasks and our design achieved the performance as expected.

Project result

Build two set of robots for two teams, respectively.
Complete the competition.
Nurture a group of well-trained new members.

Student learning and achievements

HKU students have been joining ABU Robocon competition since 2004. In recent years, more and more students join the competition, and the performances of our teams are sustainably improved.

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Some students, who have accumulated rich experiences on design and fabrication of robots based on annual competition’s rules, mentor and train junior students. As a result, such junior students would be capable of developing robots and become core members for next year competition.

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Therefore, this project is a good platform to allow students to gain hands-on and teamwork skills via design and fabrication of robots. Such skills are useful for their career development.

Lastly, through mini-Robocon for secondary school students, we can promote HKU Engineering to the future engineers. They may become part of the HKU Engineering Family and even a future member of the HKU Robocon Team. It makes HKU Engineering and our Team sustainable.

Future plan

Our future plan is to participate in the ABU Robocon 2021. Main goal is the win the local context and subsequently the Asia-Pacific context.

Sharing by supervisors

We appreciate it so much that HKU Robocon team spent efforts and time on design and manufacturing of robots and participation in the competition.

Sharing by students

“Hello. I am Alex, a team member of HKU Robocon. I have joined in since last year and have participated in designing some parts of the contest robot for Robocon 2019, as well as fine-tuning the performance of the said robot. I am a mechanical engineering student and have a great interest in robotics and control, and hence wish to pursue a future in those fields. Joining this team surely does help a lot, for example, I learned to use CAD software (SolidWorks), manufacturing processes like using the vertical milling machines to make parts for our robots (Aluminum tubes, even sometimes parts). Since I am also trying to pursue a future career in Robotics and Control, I can also have a chance to apply the knowledge learned in the control courses offered in this university to optimizing the performance of the robots. As of now, since the theme for Robocon 2020-21 is issued, I am working on the preliminary designs in hopes to speed up our R&D phase.“

Alex, Department of Mechanical Engineering

“I am Peter, a year 4 student studying Computer Engineering. I have stayed in HKU Robocon studio for 3 years witnessing victories and failures of us. Meanwhile, I have learned and applied knowledge in MCU programming and PCB designing on the robots we made, which are part of the main components in forming a robot. These experiences are unique and cannot be acquired barely from the courses we study. I am grateful that I have engaged in the team which brings me a fruitful campus life. In Robocon 2020, I will focus more on programming and I will strive hard to contribute more on our robots.“

Peter, Computer Engineering, Department of Electrical and Electronic Engineering

“Here is Heidi. It is my third year in the university and HKU Robocon Studio. I study computer science and work as a programmer. In the M2 lab, people flourish with their passion and potential. Students from various backgrounds join and meet here, working and fighting for one common goal. The contest is a rare chance that an engineering student could found to consolidate their knowledge and try out the latest technology. As a programmer, I do the automation, computer vision and strive to figure out the best strategy in the program flow. There are still a lot to learn and unknowns to solve, but it is the time we spent together here allows us to overcome all of it. The topic for 2020 Robocon is out, I am looking forward to seeing how our design is going to evolve in this year.”

Heidi, Department of Computer Science

“In the late May, we participated the competition organized by the British Model Flying Association (BMFA) in the United Kingdom. This competition is about designing an aircraft based on the requirements and confinement of specific discipline. We take the participation in the payload challenge. It aims to carry 4kg of payload while minimize the weight of the aircraft. Our team, HKUFO, planned over a year to design an aircraft to win the competition.

However, it is not that smooth during the whole process. Designing an aircraft is never an easy task. Since all our team members are inexperienced, we spent a lot of time to acquire the knowledge from reference books. We also seek for the assistance and consultation from Dr C. K. Chan and Mr C. K. Leung. We did argue. We did frustrate. We did disappoint. This is because the results of the flight tests are not always satisfactory. Nevertheless, we still designed an aircraft that we believed can win the game. But, our aircraft crashed for 3 times just a few days before the one-day competition. From unavailable condition to ready-to-fly, it took us so much time to recover it even working overnight in a tiny bedroom.

Finally, our recovered aircraft carried 4.16kg payload with merely 1.1kg empty aircraft weight. It landed successfully. Yet, we solely got the second place in the competition with 2.5 marks legging behind. It is ridiculous that I do not feel unhappy once I know the result. In contrast, I am proud of our design, proud of the concerted efforts of our whole team, proud of the spirit of never give up until the last moment. We utilized the engineering knowledge that we learnt in the past 4 years. Even though we only got a certification in term of tangible stuff, it is an unforgettable experience for me. I believed that I will remember that day for lifelong time.

This means more.“

Lai Tsz Ho, Team 3

“It was a fruitful experience to take part in the BMFA competition. I have learnt the technical knowledge in designing and manufacturing a model aircraft. Our supervisor has shared his precious experience with us in designing an aircraft model. Although our team has decided to use the traditional plane as our design, we have tried different structural design to better match with the goal of the competition. Failures occurred frequently in the past test flight because we were too aggressive on the design and hence the structure of the plane was too weak. Improvements on the plane have been made after each failure and we have learnt great lessons from it as well. The final model for the competition was completed a few days before the competition with the help of great teamwork and effort. We were able to achieve our original target which is to build a 1kg model for the competition.

But things did not go as planned when we arrived in the UK to prepare for the competition. Our model was damaged during transportation, but we were able to fix the issue immediately. However, the aircraft model crashed three time before the competition due to multiple reasons like disconnection of control cable and material issue. It was very disappointing to us and we thought we could not complete the competition with a broken model. But with the strong team effort, we all try our best to repair the aircraft within a tight schedule. We have working day and night and the model was ready for the competition just before it was started. Lots of reinforcements have been made which lowered the performance of the model. Fortunately, we were able to complete all the missions and got the 1st runner up at the end.

It might not be the best ending for us, but most important is that we did learn a lot in the process. From designing a model aircraft to building prototypes using raw material. I am thankful that I could overcome all the challenges during these months in the end with my teammates and endless support from our supervisors.“

Lai Wing Tak, Team 3

“In early June 2019, our team took part in the “BMFA Payload Challenge” held by the British Model Flying Association. Thanks to various people who have offered aid to our team, which included our supervisor Dr CK Chan, our instructor Mr CK Leung, G14 technician Mr CK Chan, etc, our team has won the 1st runner up in this prestigious weight challenge. Our effort paid since 2018 summer was also paid off. In the following passage, I am going to shed some light on my thoughts and feelings about the competition.

First and foremost, the competition taught me that building something from scratch involves complex planning, researching, designing, modelling, testing and refining. In order to build an RC plane that can be flown properly, we started our planning as early as July last year. In these 10 months time, we have gone through the steps mentioned above. Especially in 3 months prior to the competition, design of the wing has been changed 2 times for the sake of improving lift and aerodynamic performance. It is not as simple as I thought to produce a mechanical product.

Second of all, a design project requires tight collaboration between parts responsible by different people. An RC plane is composed of various parts such as the fuselage, tails, wing, payload box and wheels. It is just like any proper project done in any engineering field which requires continuous communication and collaboration between even more divisions. Preparing for this competition made me recognize the importance of cooperation and information circulation between teammates.

In the process of the competition, I have understood something that contradicts with my existing belief to quite a large extent ——- not every effort is guaranteed to be paid off. Before departing for the UK for attending the competition, we have had a few rounds of flight tests in HK. Unfortunately, most of our prototypes crashed due to different reasons like fatigue and failure of a carbon rod inside the wings, wrong electronic connection of the control, an insufficient amount of battery during a flight, etc. Frankly speaking, I have once doubted the meaning and value of taking part in this endless crash-and-rebuild cycle as I have been feeling that our effort paid has always been in vain. This is a lot different from exams and tests in which the score always more or less reflects the time and effort that a person has spent. Luckily, my teammates and I did not give up and kept on endeavouring until the very end.

Last but not least, I have enjoyed the competition on a whole. We can proudly say that we have made our greatest effort during the preparation period and the competition. Especially during our days in the UK, numerous crashes of our prototype in-flight tests right before the competition day have brought us desperation and several sleepless nights for repairing the plane. I believe that enjoying the process instead of caring so much about the outcome is one the key factors that contribute to our final glorious result of getting a 1st runner up.“

Tong Hon Sing, Team 3

“The objective of our final year project is to complete in the competition ‘British Model Flying Association 2019 University and Schools Flight Challenge 5 – Weight’. To win the competition, we had to build a remote-control plane with the highest payload to empty weight ratio. Report writing, drawings and presentation were also counted into the total score apart from the three flights scores.

In the beginning, we did not have much understanding and knowledge about how to design an aircraft. We had to do a lot of research and self-learning in order to create the first preliminary design of our aircraft in a short period of time. This has not just boosted our academic knowledge, but also the ability of self-learning.

Thought out the project, we have experienced many that cannot be taught in lectures, such as the development of engineering sense, decision making, the ways to verify your idea, creative thinking, problem-solving skills, etc. As there were many assumptions and possibilities in the design. To make our final decision, we have to do numbers of tests to find out the best solution without flying our plane as we did not have many chances to have a flight test in the airfield. By learning from failure, our engineering sense has developed so we can determine whether the structure or the selected material is feasible or not. This allowed us to work more efficiently.

Apart from the hands-on skills, we have also learnt how to present our idea to others formally and clearly. In our interim presentation and report, we did not prepare the presentation material in the view of the audience and the materials were not friendly to read and follow. We then learnt from failure and eventually, our final report and presentation were not bad.

In three days before the competition, we did three flight tests and our plane crashed in all the flight tests. We worked overnight these days to repair and rebuild the damaged parts. Although it was tiring, tough and discouraging, we did not give up. Instead, we learnt from the failures and successfully rebuilt the plane. Fortunately, our plane flew nicely in the competition and we got the first runner-up. The key of the project is not the result, it is the soft skills we have learnt instead, like team spirit, communication and corporation skills, being persevered and supportive, etc. We had to communicate well to avoid misunderstanding that made the working process more efficient which is crucial especially in those days just before the competition. Working as a team, when teammate faced any troublesome, other teammates were supportive and worked so hard to solve the problem.

Lastly, in our whole journey, we were so lucky to have our supervisor Dr. Chan, our pilot Mr. Leung and technician Mr. Chan for helping us a lot in preparing the tools and materials, teaching us so much about different aircraft structures and giving us advice on how we can improve the performance of our aircraft. Therefore, I would like to express my gratitude to their generous support.“

Yiu Wai Ying, Team 3

“Our team represented HKU in a 3-day competition, 2019 University and Schools Flight Challenge 5 – Weight, held by the British Model Flying Association (BMFA) in Buckminster, the U.K during 30th May to 2nd June, 2019. The team was honoured as the champion of the competition, scoring the highest points in report and drawing, presentation and flying round.

BMFA is the United Kingdom’s National Governing Body for the sport of model aircraft flying and one of its key aims is to increase interest in aviation and engineering through education. The BMFA Flight Challenges require students to design, build and fly load-carrying model aircraft. The competition requires each team to display design flair, technical knowledge and teamwork. The competition is judged by a panel of professional engineers and examiners, the challenge is partnered by the Royal Aeronautical Society and also enjoys the support of BAE SYSTEMS.

The competition is part of the capstone project our team has worked on for the past 2 semesters. We adopted an engineering approach to design and construct remote-controlled planes for the BMFA competition in June 2019. It aims to build a light plane to carry water load weighted up to four kilograms with a target empty weight of 1.2 kilograms to score high marks in the competition. Different aircraft components have been constructed with light materials with innovative manufacturing method to build a light plane with excellent aerodynamic characteristics. At the beginning of the project in 2018 summer, our plane weighed 1.7 kg and can only carry 2 kg payload. The plane that we used in the competition at the end weighed 1.1 kg and was able to carry a 4 kg payload.

To ensure the aircraft is safe and reliable for the competition, different tests were conducted by the group before going to the U.K., namely motor tests and flight tests.

The motor test is conducted to ensure the safety of the motor in performing the designated flight during competition. It also provided parameters for the group to select the most suitable propeller for the aircraft. Upon testing of the motor, the 12×6 propeller was selected, and the motor is proven to be safe to fly with the aircraft prototype. Five flight tests are conducted to test the airworthiness of the three prototypes. These tests provided the group with valuable information and direction to improve the aircraft on. The importance of these flight tests is demonstrated by the fact that the aircraft performance has improved as we progress to the next flight test, with the improvement in weight reduction and landing gear performance being the most significant. The result of flight test 4 is the most satisfactory amongst all, with smooth takeoffs and landings upon a modification of aircraft design from tricycles to taildragger.

One of the biggest challenges in the project and competition is weight reduction. To achieve the lightest aircraft possible, the group modified its design in all the aircraft parts. In the design stage, a lighter airfoil and an optimized wing area were designed to reduce weight. In addition, the empennage was designed with the most optimized shape to achieve a good flight performance, while reducing the overall weight. Fuselage design was also made thinner to reduce any redundant space for payload installation, and hence make the aircraft lighter. The group has also evaluated its manufacturing process to reduce any excessive materials used to produce the aircraft so that an aircraft with the lightest weight can be produced for the competition.

Our team departed Hong Kong on 26th June, one week before the competition, to settle in and prepare for the competition. During the week before the competition commenced, we performed final flight tests to examine the rolling performance on a grass runway, aerodynamic properties of the aircraft at the competition airfield. Then we made slight adjustments on the aircraft, allowing it to adapt to the local windy condition. We also explored the area around the motel we stayed at, like Grantham, Woolsthorpe Manor, where Isaac Newton was born in and got inspired by the apple falling off from the tree.

On 1st June, the flying round began. First, we brought our plane to the examiners for scrutineering. Our official payload empty weight was 1.1 kg. The first flying round is to fly without payload. Our plane achieved this with ease as it took off like a kite into the air. The second round requires us to fly with 2kg payload. Our team successfully achieved this too. The final round is to fly with 4kg maximum payload, a weight our team had never achieved to carry before in our prototypes. However, we kept our faith and the plane achieved this goal.

We would like to thank the generous support from Chui’s Student Excellence Scheme Ho Wing Hing Talent Fund. The fund allowed us to focus on the project and competition without worrying about the financial burdens. Our teamwork, presentation and communication skills are greatly refined from this competition. Our group hopes that our innovation in this BMFA competition can contribute to the world by increasing the payload-to-empty weight ratio of cargo planes, so that the air cargos can carry more goods with a low cost to maximize the income of logistics business, while delivering goods around the globe with higher efficiency.“

All members, Team 4

“Quote of wisdom – You don’t choose DBF, DBF chooses you!

Boeing 747, one of the most iconic, popular airliners and my personal favourite, has many names – the Queen of the Skies, Jumbo Jet and Humpback. The original engineers of 747 were called “The Incredibles” for they had defied gravity – building the first 747, the largest plane of their time, in just 29 months from conception to rollout. Sleeping at the desks rather than going home, pushing the flight envelopes with each improved prototype and working the fingers to the bones, I am honoured to get a similar taste of these giants’ aircraft design and build experience with my teammates in DBF. If I had a chance to propose a team name again, I would go for something like “the 6 Incredibles”, for what we were able to achieve as a team together.

Even though it is a cliché to say “process is more important than the result”, this is the most appropriate phrase I can find to describe my learning from this project. The sensation of knowing nothing at all at first and gradually evolving into a crafts-master at the end is unparalleled. The application of aeronautical knowledge inscribed into our heads from classes into the project is pretty cool. The joy of witnessing the aircraft took off and soared is nervously good and overwhelming every time. DBF is a hands-on experience full of memorable moments that is hardly comparable to other capstone projects you will find.

The friendship we forged was quite amazing given the fact that most of us didn’t know one another before the project. DBF has given us a chance to know ourselves more and learn from others. The unique characteristics of each teammate are the reason that makes our team chemistry is so unique. Inventory Manager is a jack of all trades, and will roast anyone relentlessly given the opportunity. Wing Designer has a special kind of vibe and positive attitude that make everyone less tense. Empennage Designer is passionate for aviation and has an inexplicable, persevering fondness for 芙蓉蛋飯. One, actually two, Undercarriage and the other Wing Designer, are always calm, cool on the outside but have all sorts of crazy, dark of thoughts deep inside. The bond and memories with these people are what I will cherish for life.

To conclude, the key of this project is to keep believing in yourself and your teammates, then everything will turn out right at the end. To those who are considering DBF as their capstone project and come across this passage, my advice is do not hesitate, just go for it! Even though there is absolutely no escape from the hardships once you choose DBF, I can guarantee that you will be aboard for an adventure of a lifetime.”

Cheung Yat Hei Hywel, Team 4

“I am honoured to have this chance to participate in the BMFA payload challenge. I would like to share some memorable moments during the whole year of preparation and competition. This is the first time I represent HKU in a competition. My grades at school are not really outstanding, therefore I have never thought of representing HKU. When the supervisor texted our team leader about we can join the BMFA payload challenge, my teammates and I was so happy and excited. I immediately told my floormates and family about this. I will never forget that day.

The second memorable moment that I would like to share is our first flight test. In our first prototype, as we lacked experiences and knowledge, some details were not well thought. We were so nervous before the test flight, because we thought it might very unlikely able to fly. However, it took off successfully and looking our aircraft flew was so satisfying.

I have gained a lot this year. I have learnt about the technical knowledge of designing and building an aircraft, the key to work as a team player, how to use engineering approach for a problem etc. And I have met 5 interesting people during the project. Without any of my groupmates, the project could never have been done. I am glad that I have chosen this topic for my final year project and would like to thank everyone who has helped in this year!“

Tang Nok Ping, Team 4

“The competition has ended with a great victory for HKU, but it is the friendship and technical knowledge I obtained that will last forever. At the beginning of the project, most of us were beginners who do not have much knowledge of building an aircraft. We rely much on our supervisors – Mr Leung and Dr Chan to guide us and enlighten us with innovative ideas to build an aircraft. Therefore, I would like to thank our supervisors for their efforts and guidance during the year. On top of that, I learnt a lot of crafting skills from the technicians in the G14 lab. I will never forget the day when I weld my own wiring connection with the fuse box and electronic speed control unit!

Engineering is an academic subject that often requires students to learn in a theoretical way rather than a practical way. On top of that, the judging criteria for a successful project can differ between practical ways and academic ways. For instance, despite winning the competition in BMFA with the highest score in all categories (including report and presentation) in the UK, we still only obtain a B+ grade in HKU. This speaks to the difference in judging criteria for different academic institutions, and it is somewhat difficult to draw a line as to what a successful project should be. Nonetheless, upon attending this project, I realize that both practical and theory should go hand in hand in order for engineering students to understand what they are actually learning. I am very glad that I had this opportunity to learn.

To conclude, for those who are planning to attend Design, Build and Fly in the following years, my advice is “Rome is not built in a day”. Even though at the beginning of the project you might face a challenge in understanding anything at all or struggle in building a flyable plane, you will soon succeed after a year of training in terms of running flight tests and simulations. And ultimately, joy and adrenaline will burst in your mind when you see the plane handmade by you take flight into the sky and catch your dreams.”

Chak Kwok Wang, Team 4

“DBF is really a good opportunity for final year students to learn more about design and manufacture. We have the chance to design and build our own aircraft, the Skycatcher, and I was so overwhelmed to see it took off for the first time. Thought out the project, our team spent lots of days and nights in the lab to build our aircraft. With much help and advice from Dr Chan, Mr Leung, and technician Mr Chan, I gained so much and would like to thank them again. It is so honoured to get the first place in the BMFA. To sum up, although the grades cannot represent the results we have got and the efforts we have paid, DBF is still a good experience and memory for me. Regret is the only thing I do not get after joining DBF!“

Sin Ching Cho, Team 4

“It’s my great honour to have this chance to participate as a representative from HKU in this amazing “design, build and fly” competition. As an aviation enthusiast, it is also a good opportunity for me to gain more experience and aeronautical knowledge through the competition. Also, this is a great moment to meet all aviation lovers from all over the world. What is important in the competition is the team spirit among our groupmates. It is not a one-man-work. Without them, we would not make it.

At the first beginning, we knew almost nothing about building a radio-controlled aircraft, although we all had a great passion in aviation. However, with the help and guidance from our supervisors, Dr Chan, Mr Leung and Mr Chan, we had a big improvement in our aeronautical knowledge and craftsmanship in building the aircraft. Thus, I would like to take this opportunity to thank them for the professional guidance and valuable advice. Throughout the competition, we used to crash the aircraft. We used to be frustrated. However, with the support from the supervisors and groupmates, and we believed that rainbow will come after the rain, we finally overcame it and made it to the success. And it is so honoured to win the first-place.

To conclude, it was a memorable and precious experience in my life ever. Apart from the technical knowledge I gained, the most important gain from this competition was the friendship. My groupmates and I worked together to make the aircraft with a countless sleepless night. We met aviation professionals from all over the world. It was such a great and astonishing experience meeting and gathering with aviation enthusiast!“

Lai Wing Ki, Team 4

“Although this final year project required us to start our work even in the summer of our third year of study, it is still one of the most memorable, educational and rewarding projects of my entire university life. I had the opportunity to design an aircraft’s wing, which has allowed me to learn huge amount of new knowledge that i normally would not have the chance to study and make it practical. We not only had the chance to learn how to design and build an RC plane from zero, but we also forged a strong relationship between us, filled with many unforgettable memories, for example, the first time we saw our aircraft soared in the sky. This sense of achievement has been the fuel to drive us through much difficult time. It is so satisfying that we did finally won the championship of the competition. The journey to England would remain one of my shining mark in my life!“

Li Kam Pang, Team 4

Awards

Payload Challenge 5 of British Model Flying Association 2019 University and Schools Flight Challenges

This article appears in the news from the HKU Engineering Faulty website

Three “Design, Build and Fly” teams from the Department of Mechanical Engineering dominated the Payload Challenge 5 of the British Model Flying Association (BMFA) 2019 University and Schools Flight Challenges. They won the champion, 1st runner-up and 3rd runner-up respectively after three days of competition.

The British Model Flying Association 2019 University and Schools Flight Challenges was held in BMFA Buckminster, Sewstern Lane, Grantham, Lincolnshire, NG33 5RW from May 31 to June 2, 2019. With the technical support from the Hong Kong Air Cadet Corp (HKACC) and the Hong Kong Model Engineering Club Limited (HKMEC), our teams competed the 2019 Payload Challenge 5 with other 14 teams from all over the world, including UK and USA.

Competing teams were required to design and build a radio controlled (RC) aircraft using the specified design and equipment parameters, capable of carrying the specified liquid payload. Contestants should design their aircraft to maximise the value of the ratio “payload/aircraft empty mass”. Apart from submitting a technical report for the aircraft’s design and construction with design drawings and a verbal presentation, teams were required to complete three rounds of flight missions. Each aircraft was required to complete a flight without any payload in the first round. Then the payload was increased to 2kg and 4kg in the second and third round respectively. After three days of competition, our teams completed all three missions successfully and team #4, #3 and #2 won the champion, 1st runner-up and 3rd runner-up respectively.

Dr C.K Chan, supervisor of the teams, was proud of the excellent performance of the teams. He remarked, “It was not only a competition, but also an eye-opening experience for the students. They had chances to communicate and exchange ideas with other teams on design, selection of propellers, validity of different CAD software, weight minimization methods, payload loading and unloading mechanism, sourcing of components, etc. We are grateful to have such valuable experience and we thank the University for supporting us. ”