DESIGN BLOG

Why was this project chosen?

This project was chosen as we are currently in a world pandemic and many people are experiencing loneliness as people need to spend lots of time at home without socialising. The teddy bear concept seemed a really interesting project to tackle this problem. 

 

However, instead of using a teddy bear, we decided to give the project a direction change. This is why Cosi was created. Cosi will allow people to walk into their homes and feel a sense of company, as it will be able to play their favourite song and communicate with them. 

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Project Development  

After choosing the project, the next step was the prototyping process. A brainstorming session was conducted, having, as a result, a collection of low-fi prototypes that included 3D paper figures which represented some initial shape ideas and a storyboard that showed how our object was going to work.

Low-Fidelity Prototyping (paper 3D prototypes, storyboard)

Target Audience

Cosi targets people of all ages who might need some company at home or who might just want to be entertained. The song which we have included is personalised to the group as we wanted to show an example and this specific set-up would be targeted to people who are young adults.

Market Research – Existing products & Components needed

We did some market research for some of the existing products like ours, including the past projects from the same module. By doing the market research, we found out which components we needed to order so we could start coding and making Cosi as soon as possible. Even though we ordered some extra components after starting our project and realising we would benefit from having these, these came on time giving us a few days to finish implementing them into the code and the hardware. These are the components we needed to communicate and receive feedback with Cosi using an identifier.  

Direction Change within the project development 

As we received some components, we started testing them separately. This helped us understand the functions and test for each component, which allowed us to put all together later.

Speakers + Micro SD card reader + Micro SD card

The RFID tag reader and the Micro SD card reader use the same pins for MISO, MOSI, SCK and CS. This means that when you implement both in the same board and try to run the code which contains both of their functions implemented, the code gets confused as they are two different components with different functions attached to the same pin. To fix this, we can combine two Arduino UNO boards, however, we have already physically made the design and structure of Cosi and two Arduino boards would not be able to fit. We have decided to change the outcome of the project from having a recorded voice communicating with the user as soon as the user’s tag is read by the RFID reader to having the LED matrix to display a welcoming message to the user as soon as the user’s tag is read by the RFID reader.

LED Matrix 

At first, the goal of the project was to use the led matrix to display some combination of light indicators which represent if the correct user is approaching Cosi or not. Initially, if the correct user approached the matrix was going to turn red and if the wrong user was approached the matrix would turn red. As we had the plan change by removing the SD card reader, we needed Cosi to communicate with us through a different format. We decided the matrix would be the perfect place to do so as we would be able to display messages and additionally use the colour indicators. 

Voice “Talkie” library 

To indicate that the wrong user approached Cosi, we decided to have a voice which would communicate this to the user. This decision was made after we were looking for solutions to replace the micro SD card. There is a voice program named “talkie” which is in the Arduino Library. It has some basic vocabulary and words such as “danger” which we thought would be nice to include in our Arduino project to indicate that the wrong user approached.

Design Choices Made, Steps and methods applied

We made the design choices of our product thinking on how we could support people in their everyday lives at home. Our project goals are based on 3 aspects:

• Utility: Cosi is useful to satisfy the needs of a user who wants to feel a sense of company, contributing to their daily routine. Additionally, It is designed in a way which is easily accessible for the user and satisfies the user’s needs and demands.
• Usability: Cosi is simple and efficient to use; the interaction consists of using a tag that is approached to a tag reader which recognises the owner. Depending on who is the recognised user, it creates a different output (speakers and LEDs). When it is used correctly the outcome is very satisfactory, and the process very safe and straightforward.
• Experience: Our product not only creates an experience with the user when it is used, but it can also add to the scene by just being there due to its beautiful design. When using our product, the user constantly interacts with it and, in some way, makes him/her feel less alone. 

Interactive design principles

Cosi functions through user interaction; it will only turn on once it’s owner registers the tag with the tag reader. In order for it to work as expected, Cosi was developed with a good conceptual background design, so it can be easily used by any user within the expected age range. All the key interactive components were made visible within the design so the working process is understood by the user and there is some feedback between the Arduino program and the owner. The speakers, LED matrix and the tag reader can all be seen and perceived when Cosi is used; an opening within the structure was created for the tag reader and the speakers, and the LED matrix was placed on top, as this was the best visual place in the design for the user. 

 

Extra components

Micro SD card reader + Micro SD card

Through the development process of the audio implementation with the speakers, we realised that we needed to store the pre-recorded audios somewhere other than the Arduino board, therefore we decided to purchase two extra components; a micro SD card reader and a 16GB micro SD card.  The micro SD card comes in two sizes, micro SD card to place inside the micro SD card reader and an adapter from micro to a normal SD card to connect to the computer to transfer the audios. 

Battery case + 9V battery 

The last component we had to order was a battery case and a 9V battery which we realised we wanted during the development of the structure and design of Cosi. We preferred to have our Arduino powered by batteries instead of connecting it directly to the computer as our structure for the case of Cosi is closed so we wanted to hide as many of the components as possible. Having a cable come out of the structure into the computer would look messy, therefore buying a battery was a design choice which would help our design look more minimalistic. 

Pictures and videos of major milestones/prototypes

Product design and construction of Cosi 

Hardware testing

Learning how to weld and welding our RFID tag to a connector (so the cable would be male to female)

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PROJECT TASK LIST

Description of all the major tasks of the project

General project tasks:

The main project tasks were divided into 4 sections:

• Group formation & project choice: the group was decided and after reading all the project briefs, project 6 was chosen as the first choice.
• Brainstorm & research: there was a session where ideas were brainstormed and research was carried out to come up with the final project solution. During this session, we decided to take a different approach to the teddy bear and instead create a decorative home piece. Research was also carried out to get an idea of how the project could be implemented.
• First prototypes: low-fi paper prototypes were done to get an idea of the final design of Cosi and a storyboard to show in what scenarios it could be used. 
• Final presentation: preparing this and presenting it to the demonstrators on Friday the 11th.

 

Test code & components:

RFID-RC522 Tag Reader 

RFID stands for Radio-frequency identification and can be used for applications that require identification mechanisms. The tag reader uses the same frequency as the tag to read each other. We used the tag reader to grant access to start our programme with different outcomes depending on which card has been read. The tag reader was tested by itself using the serial monitor to ensure it worked. First, one needs to check using the card reader what is the ID of each of the tags that we are using. There is a special code needed to find this out. This tag ID will later allow us to programme the code and configure if this card has been read and do certain actions with it. 

 

This is the code which uses the serial monitor to display the id of whichever card you use, it also allows you to check if the card reader works or not.

 

Led Matrix 8 x 8 

The Led matrix is used to display a greeting message to our user, it is used to communicate via writing so our user is aware that their tag has been read. The LED matrix was first tested to see if it worked using a code and the libraries of Arduino named NeoPixel. As soon as this code worked, we saw the lights of our Arduino turn on as you can see in the photo below. This allowed us to test that the hardware was connected correctly to the Arduino board. 

Code:

Speakers + Micro SD card reader + Micro SD card

The speakers were first tested using a midi soundtrack alone, the code is below.

This is the easiest way to test if the speakers work. After making sure the speakers work well, we tested them implementing the card reader into the circuit so we could store some audio and then play recorded audio/music/voice through them. This is the code which we used to play an audio file stored in the micro SD card.

Finally, we also tested the speakers using an Arduino library named talkie, this library contains a pre-recorded Arduino owned voice which without the use of a micro SD card reader/ micro SD card, we can use simple words to communicate with our audience. 

Speakers + RFID-RC522 Tag Reader + midi sound

The code from the speaker and the midi sound was implemented with the original tag reader code, here we tested that the sound would activate if we used one of the tags.

Product design & construction:

• Design of the final shape

After the prototyping process, we started thinking about alternatives on how we could improve the structure of Cosi. Our priority was to design a structure which was empty on the inside, with enough space to fit our components, being able to make holes so the speakers and LEDs matrix could be seen. But apart from this,  we also wanted it to look appealing to the user.

We had some ideas until we came with our final one, a pyramidal structure with alternating layers of different thickness and widths.

One of us has Mexican heritage, which inspired its shape, based on the Kukulcán Pyramid in Chichén-Itzá, Mexico.

• Laser-cut components

We used Fusion360, a 3D Design Software that allowed us to have an idea of the final rendered shape and also to send the different sketches to the laser cutter so that we could cut each layer with its respective measures.

We rendered Cosi with different option materials and we decided wood was the most suitable and appealing material to create it.

• Construction of Cosi

When having all the different layers grouped in one structure, it was time to arrange how the components would fit inside. We had to decide how the speakers and the tag reader would fit. We made a total of 3 see-through holes, 2 in one side for the speakers and 1 on another for the tag reader.

After this was made and we checked everything fitted as expected, we glued all the layers and our final shape was built.

Meetings

Meeting 1 (13th of November)

During this meeting the project we wanted to work on was decided – “Your Own Talking and Loving Teddy Bear” project 6. However, we wanted to create a different outcome, instead of making a Teddy Bear the idea was to make a decorative piece, which would look nice in one’s house. The next days were used to brainstorm ideas and do some research.

Meeting 2 (16th of November)

This meeting consisted of creating the final design and prototypes of how the decorative piece would look like, we decided to name it “Cosi”. After this, we created a storyboard showing how Cosi would function and when it would be used. Once this was finalised, a list of components was created, along with the tasks of each. Research was done on the components needed and they were ordered throughout the following days (speaker, SD card, RFID reader + tags, battery).

Meeting 3 (23rd of November)

The components arrived and the current goal was to get each component to work individually. Test code was created for each of the components and implemented to check that the hardware and software were working properly. We also carried on the construction of Cosi (done throughout the weeks).

Meeting 4 (30th of November)

Update on how the test code was functioning. Trying to combine some components to work with the same code.  

Meeting 5 (2nd and 3rd of December)

Assembling all the components together and trying to implement them so they work with the same code. Working on the construction of Cosi (in Maker Space)

Meeting 6 (6th of December)

Finalisation of documents, presentation and setting up the final product. 

Work distribution

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MAKER MANUAL

Overview of pictures/videos and a description of the final product

Tools and supplies section – Hardware required to make it 

1 x RDIF MFRC522 Tag Reader 

2 x Tag 

1 x LED 8×8 matrix (6.5cm x 6.5cm x 0.3 cm)

2 x Speakers  (7.0cm x 3.1cm x 1.6cm)

1 x 9V Battery holder (6.8cm x 3.3cm x 2.1cm)

1 x 9V Battery 

40 x multi-colour wires 

1 x Arduino uno – 7.5cm x 6cm 

1 x Breadboard – 5.5cm x 8.5cm 

1 x Structure to store electronic components

Layout and circuit diagram section

Build section (how you made physical aspects)

Tools and supplies needed for the structure

• Fusion360 (Free 3D Software)
• Adobe Illustrator
• 1 x  A3 Plywood plank – 6mm thickness
• 1 x  A3 Plywood plank – 3mm thickness
• Laser Cutter Machine
• 80-grit sandpaper
• Band saw
• Superglue

1. First, we 3D modelled our structure design. This is composed of alternating one by one layer of 3mm and 6 mm thickness. The total width and height of the modelled structure were 225mm x 200mm.

2.Then, each sketch for each layer was sent to the laser cutter.

3. After having all the physical layers ready, it was time to put them all together to see where it was best to place the speakers and the tag reader.

4. Then, we had to make holes with the band saw and we sanded all the layers.

5. Now everything was ready to glue all the layers together one by one.

6. Finally, the components were put together inside and Cosi was created.

7. After everything was finalised, we thought about the branding of Cosi and we decided to make a logo. We used Adobe Illustrator in order to do that. This logo was also sent to the laser cutter and we tested different sizes to find what was the best size to put on the structure.

Commented & well-organised code