Chair Challenge


Incorrect sitting posture may do harm on people’s health. One of the important reasons for incorrect sitting posture is that the height of chairs and desks do not fit the individuals who use them.

Is it possible to invent a special chair?

  • When people sit with an inappropriate posture, the chair can warn people sitting on.

  • The height of the chair can be adjusted so that it can fit for people in different heights.



Product development

  • Conduct market analysis

  • Conduct competitor analysis

  • Compare different design ideas

  • Product developing and testing

  • Do marketing and get feedbacks

  • Make product improvements according to the feedbacks

Soft skills

  • Sense of goal

  • Awareness & skills of asking for help (written, spoken, networking)

  • Communication skills

  • Trust for group members

  • Deck searching skills

  • Collaboration and teamwork ability


It is worth noting that, each abilities shown here should have according methods of accessing, then we can show the assessment results to our clients, to prove that these abilities/skills are enhanced through this PBL course.


Goal: Let the students assess the product & process

Self assessment on products  

  • Innovation

    • Is this product able to make people do what they couldn’t do before or can do better now?

    • Do people think this product is innovative enough after the trial?

  • Market

    • Whom should I sell to?

    • How much should you charge?

    • How many similar products are sold in the market right now?

    • How much can you sell over time?

    • What will your profit be?


Peer assessment on process

  • The techniques and skills used in creating this product  

  • Involvement (focus on the activeness and participation during the discussion)

  • Contribution (focus on the output)



About why we choose the idea and why we think it is more innovative


  • Daily-life Demands

  • Health

As people are spending increasingly more time sitting, working in the office, watching movies in the theater, enjoying a meal at restaurants and playing games at home, chairs have been a crucial part in daily life. It has been shown that on average, people with sedentary jobs sit 9.95 hours at working days and 8.07 hours when not working. It is therefore fair to say that such innovation of chairs would meet the individuals’ daily-life demands and become a necessity in the near future. Additionally, though, health issues caused by sitting postures have been quite serious, especially during this decade. Chairs, which have a direct connection with people’s posture when sitting, are called for a change in a healthier way.  

More innovative than other normal chairs, the chairs you are going to invent can also benefit people’s health. It is unique and has not brought into market at present.

Our Solution: “PostureIT”        

Our product will have sensors that measure the distance between people’s back and the chair. It will send the notifications to the people sitting in a bad posture and remind them to stand up and have a rest.

A. Sensor (with ultrasonic or infrared)

  • Distance between screen and eyes

  • Gesture/movement (inertial measurement unit)

  • Pressure (on the chair surface)



B. Computer Vision

  • Recognize key parts (joints, shoulders, heads, eyes, waist, etc.) from photos

  • Eliminate unrelated info (noise) from photos(or sensor data)


C. Machine Learning

  • Extract features from database(photos of sitting human, sensor data, etc.)


D. Prototype

  • Put everything in ideal and easy condition

Provide an answer by clicking on "Map" and then on "Add an Answer".

Results, Analysis and Discussion

1.  Luo Xue (16.08.2018 pm 07.27.14)
Recommend of Chair Challenge

I think the topic is worth working on it.

Nowadays, many young people get lumbar spondylosis because of sitting for long time using poor posture. Once we form a sitting posture, we can hardly correct by ourselves. On the one hand, the chair or other tools need to be used to help people correct poor postures. On the other hand, it's also good for their eyes.

But still there are many details that the products need to improve. Such as the noise when work or the comfort level and so on. In the future, hope it will be built perfectly.

2.  Meng Chenyu (16.08.2018 pm 08.31.18)
a meaningful assignment

Thank you for sharing.

1. This project has a strong connection with the real life.
2. I think it is good that you also ask students to do market research instead of just making products.
3. Your prototype is great!

I think the problem description can be more open. The description "Is it possible to invent a special chair?" may limit the student's thinking. If the solution to the incorrect sitting posture is limited to improving the chair design, there are not many types of products that students can make. Their solution may be very similar to the teacher's example.

3.  rozenblum yael (16.08.2018 pm 08.33.04)
Peer assessment

Dear Fourth Group,

I think you have chosen to deal with a very important problem that concerns many of us. Most of us spend many hours sitting and sitting incorrectly has many implications on our health.

A large part of your target population does not work in one place, especially today in the era of shared spaces or students who spend many hours sitting in Different classes and sensors that can be attached to any chair can indeed be a solution to this problem.

However, according to the video, the chair appears to operate with 4 sensors, which increases its cost and therefore reduces the target population. In my opinion, distance measurement can also be done by 2 sensors and thus reduce the cost of the chair.

In addition, there are companies or meeting rooms to which you can not enter with a mobile phone. also, many people prefer to avoid holding the cell phone close to them during school or work to avoid distractions and  therefor you should find another way to get information from the sensors that does not depend on the mobile phone.

The guidelines you gave was clearly and contributed to the task, especially the guiding questions in Chapter 3. Providing instructions by questions helps the student to understand whether his product answered these questions or not.

I very much liked the instruction for the teacher to let the students evaluate the product and the process. Self-esteem contributes greatly to the development of critical thinking, which is one of PBL's goals.

In my opinion, it was correct to add the part of each of the requirements to the final score in order to focus the student on what is most important in the work.

In conclusion, I think you have identified an important problem that concerns many people and found a great solution. I personally would have been happy for such a product!

Best regards,

Yael Rosenblum

4.  Ren Ruijing (16.08.2018 pm 09.34.12)
Peer Review_Jiangzhuo Lin

Their work is amazing for providing us with such practical method, which prevents us from hurting our spines. I personally have been through such tough situation for working too long and get the backache afterwards. But I have a question about whether the sensor would be too sensitive every time you’re not in the correct posture. Therefore avoiding causing unnecessary problem for the user will need to be carefully considered.

Also I don’t think every individual shared the same correct posture. The chair should be adaptable to people in different shapes.

Except the problems listed, I think the product is quite promising. Way to go team four!!

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