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MAE 156B

Tongue Touch Mouse & Keyboard

Proof of Concept Presentation

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Group N8: Jesus Salazar, Punit Aswani, Jiahuan He,

Garrett Almeida, Kwangbok Roh

Roh 1

Brief Overview Of Project

• Jason Eldred, our sponsor, is working on a tongue-touch device for our client, Stacy Bibb.
• Previous design is shown on the right.
• The device allows Stacy to click, type and browse on a computer.

Roh 2

Stacy with his current mouse and keyboard system.

Copper Wire- Contact Point

Alligator Clips

Halloween Mask- Chin Strap

Problem Definition

• While the current device is successful in operation, there are issues with:
• Headset comfort
• Current headset: halloween mask
• Device movement and rotation
• Current sensor attached to mask by just two zip-ties
• Capacitive sensor reliability
• Grabbing the wire causes capacitive interference and false positives

Huan 3

Current Status of Project

• Multiple 3D printed versions of our Chin Guard
• The most recent version (“The Ingenium - Version 1”) is shown on the right.
• All items have been purchased and received.
• Preliminary Capacitive Interference tests completed.

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Huan 4

Slots

Cat5 Keystone Jack Insert

Ventilation Holes

CPAP Strap Anchor Points

The Ingenium

Cat5 Keystone Jacks

High Risk Components

• Chin Guard - “The Ingenium”
• Geometry must satisfy comfort requirements and fit the Cat5 Keystone Jacks properly.
• Copper Capacitive Contact Points
• Must be food-safe while producing accurate capacitance readings.
• CAT5 Ethernet Cable and Cat5 Keystone Jacks
• Should easily attach/detach to the chin guard
• Capacitive/Board Program
• Should ensure reliable capacitance signal (no noise)

Jesus 5

CAT5 Ethernet Cable

Copper Capacitive Sheet Metal

Key Decisions - Chin Guard:“The Ingenium”

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• Not only several prototypes have been printed out but also tested on face
• For Stacy’s comfort the major goal now is to test the model on him and attach silicone putty accordingly

Jesus 6

Slots

Cat5 Keystone Jack Insert

Ventilation Holes

CPAP Strap Anchor Points

The Ingenium - V1

The Ingenium - V0

The Trident

Key Decisions - Food Safe Coating

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• Current Progress:
• Photo 3: sample coating on a single strip
• Photo 4: Prototype coating with MAX CLR�
• Further Test required
• Determine it’s capacitive sensing property.
• “Taste” issue
• Short cure time

Roh 7

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Key Decisions - CAT5 Cable Choice

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Punit 8

Unshielded Cable

Unshielded CAT5 Cable

• Multiple Wires (8)
• More Flexible
• Thinner
• Shields normal household EMI

Shielded CAT5 Cable

• Multiple Wires (8)
• More Rigid
• Bulkier
• Capable shielding of EMI and some capacitance

Key Decision: Unshielded CAT5 Cable would be our first choice for design/test

Key Decisions - Capacitive/Board Program

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Punit 9

• What Works?
• Strong Direct Signal
• What Doesn’t Work?
• Strong Oscillations to Zero while touching
• Indirect Contact Signal Increase
• Noisy�(many random spikes)

Key Decisions - Capacitive/Board Program

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Punit 10

• What Works?
• Strong Direct Signal
• Unaffected by Indirect Contact
• Controlled Oscillation
• No hints at noise
• What Doesn’t Work?
• Indirect Ground Contact lowers signal

Key Decisions - Capacitive/Board Program

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Punit 11

• Both Tests Given Low, Similar Sampling Rates �(Better matches final product sample rate)
• CircuitPython: 139 samples/sec
• Arduino: 146 samples/sec
• Arduino 2nd test: 5963 samples/sec (fastest) �(Not Shown) - Less Noisy, but still hints
• CircuitPython Wins!!
• Greater Reliability
• Why? Believe it has an accelerated program which either:
• Adjusts sampling rate to avoid noise
• Filters printed/usable capacitance data
• Further Application
• Applying code and setup to Final Design

Capacitive Test Setup:

CAT5 cable and Adafruit CPB

Key Decisions - CAT5 Cable Connection

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• Keystone Jacks make the cable easily to remove and replace for maintenance
• Jack will mounted to the chin cup using the built in locking lugs
• Modify the CAD design of “The Ingenium” in order to secure the Cat5 Keystone Jacks on the chin guard for ease of use

Garrett 12

Proof-of-Concept Demonstration

Garrett 13

Proof-of-Concept: Results

• Unfortunately, the prototype does not function properly
• Activates action for two tabs when only touching one
• There is crosstalk between channels
• Could be from wires or tabs being too close together or from the keystone jack
• Further testing/troubleshooting is needed
• CAT5 cable hits your chest during downward head movements

Garrett 14

Cat5 Keystone Jacks

Possible Design Solutions

Jesus 15

“The Ingenium” - Version 2

• CAT5 Keystone Jack inserted at a 90° angle
• Wiring might get complicated
• More compact design

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• CAT5 Keystone Jack inserted at a 180° angle
• Wiring is straightforward
• The insert makes this design more bulky

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“The Ingenium” - Version 3

Cat5 Keystone Jack Insert

Cat5 Keystone Jack

CAT5 Slots

Timeline for Future Plans

• All the parts have been purchased and machined at least once for the current prototype
• Unless something else needs to be purchased to fix the problem

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CPAP Strap

The Ingenium

Cat5 Cable

Cat5 Keystone Jacks

Garrett

Plastic Set Screws

Unresolved Questions

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• How to make the application of silicone putty inside “the Ingenium” to best fit Stacy’s chin shape?
• When should the team take the new design to Stacy’s house and test on him?
• What’s the problem with the current setup of our model that the capacitive touch points are not functioning properly?

Huan 17

Project Management: Gantt Chart

Huan 18

Questions?

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