One concern was how the electronics would be mounted inside the otter, as there would be quite a few components needed to make sure that the otter performs its function. This meant that the inside of the otter had to be designed in order to incorporate these parts.

Due to the lack of resources because of COVID-19 these developments were not able to be physically tested.

Key Components:

• Raspberry Pi 0
• WIFI Module
• High Quality Mini Speaker Module
• Omnidirectional Mini Microphone
• Noise Cancelling Mini Microphone
• Mini Microphone
• Rechargable Battery

The main components will be fitted inside the body in slots on the inside walls, as shown above, however the LEDs, mic and speakers are located closer to the front and the battery and induction coil are located in the front right paw of the otter. The two halves of the otter are joined together with pins that fit into holes located at points along the otters body.

The microphones are located at the front near the face as when the user talks they will naturally talk to the face, therefore it is the best place to put them so they detect the users voice more clearly and can gather better voice samples. The speaker is positioned near the nose so the holes that are needed look like the whisker holes on the otters face and so the user can hear the responses.

Speaker Quality:

One of the things that I had to do to make sure that the users wanted to use the product was to make sure that the sounds produced by the otter were high quality and did no sound tinny or distorted. In order to do this I made sure to use a high quality speaker and provide enough openings so that the user was able to hear the noise clear and distinctly.

To find a good quality speaker a range of speakers were looked at, and the ones that had the highest frequency range were selected, as these would be able to provide the highest quality resposes due to the otters shifting in pitch when it makes noises. There are a selection of speakers below:

• https://uk.farnell.com/kingstate/kdmg13008l-02/loudspeaker-micro-13mm/dp/1299881
• https://uk.farnell.com/kingstate/kssg1508/transducer-speaker/dp/1502737
• https://uk.farnell.com/multicomp/mckp1227sp1-4721/transducer-speaker-rx-1-3khz-86db/dp/2396076
• https://uk.farnell.com/visaton/2823/pcb-mount-speaker-23-mm-8-ohm/dp/2357167

In order to find which speaker was the best, user testing would have been done, however due to COVID-19 this was not possible. The process that would have been done would have been, to take all four of these speakers with high frequency ranges, and use them to play the otters responses in front of users. The users would then decide on which speaker was the highest quality, and this one would be chosen for the otter.

Microphones:

The idea of having multiple microphones is mentioned in the Eyes Providing Acknowledgement section, however it will be explained a bit further here. The otter will have three microphones located in its head, the task of each microhpone will be explained below.

• Omnidirectional Mini Microphone

This microphone will be used as the when the otter is placed down, perhaps not on its charging station, the user could be anywhere around the otter while talking to it, therfore an omnidirectional microphone is needed, so it can pick up on what the user is saying, no matter what direction they are in.

• Noise Cancelling Mini Microphone

The noise cancelling mic was needed as the otter will need to be able to detect background noise and cancel it out so that the voice samples recorded are high quality and can be used to better the quality of the algorithm and responses.

• Mini Microphone

The normal microphone would be used as another method of recording the voice samples from the users so that the AI algorithm can learn more and provide better responses based on the users mood.