Todays Agenda: Project overview Customer needs and engineering - - PowerPoint PPT Presentation

Dynamic Keyboard IV Team

Doug Hemink (ME), Dave D’Allesandro (ME) Michelle Sadallah (EE), Devin Blau (EE)

Today’s Agenda:

• Project overview
• Customer needs and engineering specifications
• System architecture
• Concept selection
• Mechanical design overview
• Electrical design overview
• Test results
• Current state
• Next step moving forward

The overall goal of the dynamic keyboard project is to create a PC keyboard that would enrich text communication with expression via typing force. Major Project Goals:

• Full understanding and recreation of previous dk team

progress

• Elimination of “ghosting” from the dk system
• Development and creation of a test bench/stand
• Creation of a standardized calibration system
• Structural reinforcement of the current dk system
• Exhaustive testing of the current dk system
• Contact and schedule user/customer testing for Spring
• Create a comprehensive user manual for dk

Customer Needs and Engineering Specs

Customer Need # Description CN1 Ability to portray expression through learned ability CN2 Integration to PC through standard connections CN3 Ability to differentiate individual key strike events, and associate them to corresponding sensor events in time. CN4 Simple keyboard functionality CN5 Must be reliable CN6 Establish a high level of device precision CN7 Design or consider other keyboard configurations for future teams Engr.

• Spec. #

Specification (description) Unit of Measure Ideal Value ES1 Keystroke has tactile Feel Boolean Yes ES2 Individual keys will be able to withstand at least 5N of force Max force (N) 5 ES3 Total component costs Dollars ($) <1000 ES9 Precision of force sensor % error ±10% ES17 Keyboard drivers

• Original

ES20 Type of PC Interface Type USB ES21 Paired Character Data Boolean Yes

Proposed System Architecture

User Input Original Keys Feedback Mechanism Original Keyboard Membrane Sensor Martix Internal Frame Mechanical Stop (threashold) Micro Controller PC Sensor Controller USB Hub Hardware Casing Modified Keyboard System Original Controllor

Design Pros Cons Schematic Existing layout  Easy to Modify  Already Built  Currently “works”  Has been modified for desire outputs  Meets 90% of Customer Needs  Suspect Key Functionality  Still doesn’t emulate keyboard feel  Lots of potential fail points Proposed Concept #1 – Continued Keyboard Enhancements  Aesthetically pleasing  More structurally sound  Shouldn’t impact functionality  Attempt to get more accurate force readings and ranges  Low Cost  Improvements may have diminishing returns  Mainly mechanical based improvements  Keyboard still no longer made  Chance of breaking components Proposed Concept #2 – Neophrene Keyboard  Aesthetically pleasing  More structurally sound  Shouldn’t impact functionality  Would eliminate most translational force losses  Increase definition in sensor readings  Possibly Waterproof/Damage Proof  Mostly new Method- Built from scratch  Costly  Completely different direction than currently

• n

Keyboard Electronics Keyboard Electronics Electronics Keyboard

Concepts Considered

Concepts Considered Continued

Mechanical Design Modifications

• Previous backing severely

compromised structural rigidity

• Allowed for Flexing of keyboard

during use

• New backing machined from

stock back plate only removing a small slot for electronics

• Greatly Improved structural

rigidity, eliminating flexing and increasing functionality

Mechanical Design Modifications

• PCB board previously located by large holes

around small threaded rods

• Allowed for movement and misalignment of

board in respect to keys

• Spacers machined to keep larger holes

concentric to small threaded rods

• Spacer length machined to also allow the PCB

board to float between keys and back plate

No spacer

• Freedom to move

Spacer

• Holds board

concentric

Electrical Design Modifications

• Implemented and updated software for new keyboard backing.
• Generated output and tested functionality with new keyboard model.
• Specific key calibrations
• Row Modification
• Force Sensor Testing
• USB Hub Replacement
• Modification of demo program
• Modification to native threshold software
• Attempts at double Arduino integration
• PCB Arduino removal

70 75 80 85 90 95 A S D F Average Force Read Out

Sample Test Results Test results show there are some errors between individual force sensors. This could be due to the force sensors themselves, and/or the keyboard rigidity. These will need to be characterized further.

Current State of The Project

Major Goals Achieved:

• “Ghosting” eliminated through Mechanical Modifications
• Structural Rigidity Greatly Increased
• Keystroke has tactile feel. “feels like a keyboard”
• Created a comprehensive user manual for DK3
• Developed and created stand for testing
• Lots of Positive feedback at Imagine RIT

Moving Forward

Future improvements:

• Further testing to create a standardized calibration system
• User testing through NTID
• Use of a keyboard with a single dome pad

With that being said, this project is ready to be passed on to the next steps of software development.

Summary of Results

Entire electrical and mechanical package was upgraded to provide error free data. The aesthetics of the DK now meet spec. Data was captured successfully by the DK3 team and customer testing protocols are under IRB review.

Questions?