Traffic Light for Color Deficient DriversItzel Cantu2012-2013

Engineering Design and Development 1A

Topic Background•Deuteranopia: A form of colorblindness characterized by insensitivity to green•Protanopia: defective perception of red and confusion of red with green

Color Deficiency Males Females

Protanopia 1% 0.01%

Deuteranopia 1% 0.01%

Protanomaly 1% 0.01%

Deuteranomaly 5% 0.4%

Overall (red-green) 8% 0.5%

Tritanopia 0.008% 0.008%

Tritanomaly Rare Rare

Rod monochromatism Rare Rare

Cone monochromatism Rare Rare

Problem Statement

According to ophthalmologists and transportation engineers worldwide, color

blind drivers have slower reaction times in distinguishing color coded signals,

like traffic or brake lights, on the road when behind the wheel. The hazard of

color blind drivers has existed since the industrial revolution, but only came

into awareness much later through the increase of color blind individuals who

learned of their deficiency by unique experiences, individuals who account

for 10% of the population today.

Justification: Article 1Whillans, M. (1983).Color-blind Drivers' Perception of Traffic Signals.Can Med Association, 128, 1187-1189

•surveyed groups of drivers: group of color blind and color normal individuals•Included opinions from blind people

•questionnaire was given at the British Columbia Ministry of Transportation for people who were successful applicants for a driver’s license who failed to pass the color vision medical exam

•8% of males are color blind•All but one admitted to difficulties with traffic signals

Justification: Article 2US Department of Transportation Regulations

Medical examination; certificate of physical examination. - Federal Motor Carrier Safety Administration. (n.d.).Federal Motor Carrier Safety Administration. Retrieved October 1, 2012, from http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.aspx?reg=391.43

Physical qualifications for drivers. - Federal Motor Carrier Safety Administration. (n.d.).Federal Motor Carrier Safety Administration. Retrieved October 1, 2012, from http://www.fmcsa.dot.gov/rules-regulations/administration/fmcsr/fmcsrruletext.aspx?reg=391.41

•state the driver federal regulations, specifically the medical examination requirements, and prerequisites to qualify for a driver’s license set forth by the US Department of Transportation – Federal Motor Carrier Safety Administration.

Justification: Article 3Cole, B. (2002). Protan colour vision deficiency and road accidents. Clinical and Experimental Optometry, 85.4. Retrieved September 25, 2012, from http://onlinelibrary.wiley.com/doi/10.1111/j.1444-0938.2002.tb03045.x/pdf

•reviews the level of risk of road accidents due to protan color vision deficiency and talks about the different severity of color blindness and its impact on driving•article re-analyzes data taken from a previous study

Justification: Article 4Atchison, D. A., Dain, S. J., Pedersen, C. A., & Wood, J. M. (2003). Traffic signal color recognition is a problem for both protan and deutan color-vision deficients. Human Factors, 45(3), 495+. Retrieved from http://go.galegroup.com.catalog.stisd.net:2048/ps/i.do?id=GALE%7CA111350427&v=2.1&u=tlc019162126&it=r&p=GPS&sw=w

•studies the effects of color blindness on driving. •sampled 69 people of whom the majority was color blind

•tested the accuracy of identifying traffic light colors and the response times and compared the color blind group to the color normal group

Justification: Article 5Cole, Barry L. (2004). The handicap of abnormal color vision. Clinical & experimental optometry : journal of the Australian Optometrical Association, 87. Retrieved from http://www.biomedsearch.com/nih/handicap-abnormal-colour-vision/15312030.html

•investigated a wide range of problems associated with color vision deficiency. It analyzed all aspects of a color deficient person’s life and elaborated on the problems. •People have noted from a 20-40 percent difficulty when dealing with traffic signals.•95% and 82-87% fail color vision exams

Attack Plan

Justifications

Education: (study)

Law:

Safety: Health:

Technology: (study)

US Department of Transportation Regulations: Medical examination; certificate of physical examination. - Federal Motor Carrier Safety Administration.

Atchison, D. A.: Traffic signal color recognition is a problem for both protan and deutan color-vision deficients. Human Factors

Cole, Barry L. (2004). The handicap of abnormal colour vision. Clinical & experimental optometry : journal of the Australian Optometrical Association

Cole, B. (2002). Protan colour vision deficiency and road accidents. Clinical and Experimental Optometry

Whillans, M. (1983). Color-blind Drivers' Perception of Traffic Signals. Can Med Association

Similar Solutions

B

Brainstorming Matrices

Phase 1

Phase 2

STEM PrincipalsThe three cone types have different peaks within the color spectrum:1. Short wavelength peak - ~4202. Middle wavelength peak - ~ 5303. Long wavelength peak - ~560

Normal human can see wavelengths between 400 nm and 700 nmRed has wavelength of 650-700 nmBlue 400-450Green ~450

•brain determines what color it is seeing through ratio between the signals it receives from each of the three types of cones. •white light is mixture of all wavelengths from 400 to 700 nm

Project SolutionIn order to enable color blind people to distinguish the traffic signal color at a faster rate more precisely, the solution would be low cost, easy to implement and work at night and during the night and day and would still allow non-color blind people to identify the signal color.

Traffic Light Shape Plates

X

Solution Justification

Solution would reduce risk of accident resulting from color deficiency and hesitation. Design would be universal, easily implemented, and unquestionably understood by color blind as

well as normal vision people.

Design ViabilityRATING Expert 1:

Patrick Montague

Expert 2:Luis Alvarez

Total

Reliability 5 5 10

Cost N/A 5 5+

Ease of implementation 4 5 9

Ease of Understanding 5 5 10

Feasibility 5 5 10

Ratings 1-51: Okay2: Somewhat good3:Good4: Very good5: Excellent

Design Criteria•Function: decrease hesitation and reaction times resulting from color identification while driving•Form: look exactly like present traffic lights, but the cap would have an appropriate shape illuminated in white light•Ergonomics: withstand the forces of nature and would be bright enough to be seen at all hours of the day while not being subject to glare that would impede detection•Aesthetics: (plastic making the white color)

• green signal would now have an arrow made of white light surrounded by green light

•The yellow signal would, similarly, be a white triangle surrounded by yellow light

•The red signal would have an x pattern of white light to contrast the red light

•Safety: be effective at least 98% of the time•Ease of access: be accessible by the city’s traffic safety department and implemented on every street corner•Implementation: Cost less than $50

Solution Parameters1.Device must allow for correct color signal

identification at a minimum of 45 ft. and must be effective 98% of the time.

2.Device must minimize reaction time to 1.5 s at 45 ft.

3.Device must cost less than $504.Must work for both color deficient and color

normal people.5.Must function effectively at all times of day.

Concept Model and Sketching Refinement

Traffic light with door for reference-

Technical Drawings

Technical Drawings: Phase 1

Itzel CantuEDD 1A

Technical Drawings: Phase 2

Itzel CantuEDD 1A

Material ListMaterial Vendor Quantity Cost

Traffic light Durasig 1 Donated

14 mm wire The Home Depot I spool 7.00

60 watt light bulb Wal-Mart 3 4.37

Single pull double throw switch

The Home Depot 3 3 @ 2.07 ea.

Junction box The Home Depot 1 2.18

Cover plate The Home Depot 1 1.35

Spade terminal The Home Depot I box of 70 ct 6.97

Cellophane Wal-mart 1 bag of 70 ct 1.99

Tools and Safety•Drill with drill bit•Jig Saw•Wire cutters•Scissors•Masking tape•Pliers•Exactoknife•Power Strip/ Extension cord

•Wear goggles•Tie hair•Keep fingers away from sharp

objects•Brush, do not blow• Clamp and secure whatever you

are working on.•Mark the places to be cut. •Start slowly and slowly increase

speed.• Vary the pressure.• Don’t force the tool, let the

machine do the work.• Withdraw the tool often while

drilling to remove chips.• Use a side handle and hold the

tool firmly with both hands.

Assembly Procedure

To built prototype from used traffic light:1.Re-wire insides to function in individual series connected to spdt switches2.Cut shapes on cover plates

A.Make shape with masking tapeB.Drill holes into cornersC.Cut from corner to corner with jig saw

3.Cover holes with clear cellophane4.Reassemble (replace caps)

Assembly Process Timeline

Feb22

24:Acquired traffic light

26

28:Tested Functionality

4:Wired lights in series

March2 8 10 12 14 16 18 20 22 24 26

6:Began wiring SPDT switches

19: cut shapes in caps

25: wired spdt switches and made connections to power supply

Pictures of Construction

Pictures of Finished Prototype

Timeline of Testing

March

27:Began testing and double checked functionality

28

31:

April

1:Refined testing strategy and tested

30: 26:

Methods of Testing1.Set up light vertically with control panel on stool2.Replace cap cutouts to represent past traffic

light3.Toggle random light on and record the light

color, color stated by test subject, and reaction time. 4.Repeat 5 times. 5.Turn lights off and repeat step 36.Remove caps and repeat step 37.Turn lights on and repeat step 38.Repeat steps 2-7 for each test subject

Physical Testing

Testing with lights off: nightTesting with lights on: dayRecording data for past traffic light for control or standardMeasure reaction timesRecorde colors to measure accuracy

DataNIGHT TEST Current Light Solution

Test Subject: Trial: Actual ColorColor Perceived Time

Color Perceived Time

1 1 Yellow Yellow 1 Yellow 0.6Control 2 Red Red 0.6 Red 0.6Sandra 3 Green Green 0.5 Green 0.5Mink 4 Yellow Yellow 0.8 Yellow 0.4

5 Green Green 0.6 Green 0.72 1 Yellow Red 2.7 Yellow 0.8

Jun Kim 2 Green Green 2.9 Green 1.1 3 Red Yellow 2.5 Red 0.8 4 Yellow Yellow 2.9 Yellow 1.2 5 Green Green 2.9 Green 0.9

3 1 Green Green 1.9 Green 1.3Allen Abram 2 Yellow Yellow 2.1 Red 1.9 3 Red Red 2.2 Red 1.8 4 Red Red 1.6 Red 1.7 5 Green Green 1.7 Green 1.5

4 1 Yellow Yellow 0.3 Yellow 0.3Alex Rojas 2 Red Red 0.8 Red 0.6 3 Green Green 0.5 Green 0.6 4 Yellow Yellow 0.8 Yellow 0.4 5 Red Red 0.5 Red 0.4

5 1 Green Green 0.8 Green 0.6Kevin Lee 2 Red Red 0.7 Red 0.8 3 Yellow Yellow 0.6 Yellow 0.5 4 Red Red 0.9 Red 0.6 5 Yellow Yellow 0.6 Yellow 0.9

Data, Cont.DAY TEST Current Light Solution

Test Subject: Trial: Actual Color Color Perceived Time Color Perceived Time

1 1 Red Red 0.7 Red 0.5

Control 2 Green Green 0.5 Green 0.8

Sandra 3 Yellow Yellow 0.6 Yellow 0.3

Mink 4 Yellow Yellow 0.6 Yellow 0.7

5 Green Green 1.1 Green 0.6

2 1 Green White 1.9 Green 1.5

Jun Kim 2 Red Yellow 1.9 Red 1.1

3 Yellow Yellow 1.9 Yellow 0.6

4 Red Red 2.3 Red 0.9

5 Green Green 2.9 Green 0.6

3 1 Green Green 1.9 Green 1.5

Allen Abram 2 Yellow Yellow 1.8 Yellow 1.2

3 Green Green 2 Green 1.5

4 Yellow Yellow 1.7 Yellow 1.3

5 Red Orange 1.6 Red 3.1

4 1 Green Green 0.5 Green 0.3

Alex Rojas 2 Red Red 0.4 Red 0.3

3 Red Red 0.5 Red 0.4

4 Green Green 0.4 Green 0.3

5 Yellow Yellow 0.7 Yellow 0.3

5 1 Yellow Yellow 0.8 Yellow 0.6

Kevin Lee 2 Red Red 0.9 Red 0.5

3 Green Green 1.2 Green 0.5

4 Red Red 1 Red 0.1

5 Green Green 0.8 Green 0.6

Data Analysis

NIGHT TEST Current Light SolutionTest Subject: % Accurate Average time % Accurate Average time

1

100 0.7 100 0.56Control

Mink2

60 2.78 100 0.96Jun Kim3

100 1.9 90 1.64Allen Abram4

100 0.58 100 0.46Alex Rojas5

100 0.72 100 0.68Kevin Lee

DAY TEST Current Light SolutionTest Subject: % Accurate Average time % Accurate Average time

1

100 0.7 100 0.58Control

Mink2

60 2.18 100 0.94Jun Kim3

80 1.8 100 1.72Allen Abram4

100 0.5 100 0.32Alex Rojas5

100 0.94 100 0.46Kevin Lee

Conclusion

Cumulative Averages

Current Light Solution

% AccurateAverage Time

(seconds) % AccurateAverage Time

(seconds)

Night Test 92 1.336 98 0.86

Day Test 88 1.224 100 0.804

Reflections

•Future tests would analyze•Effectiveness of LEDs•Effectiveness of black light•Concept adaptability to other light models

•Future tests would make experiment double blind by switching positions of traffic light colors

Thank You•Dorian Cantu•Patricia & Eliseo Cantu•Mr. Ponciano Longoria, City of Edinburg •Mr. Coalson•Mr. Montemayor•Mr. Patrick Montague

•Mrs. Mink•Luis Alvarez•Marissa Reyes•Kevin Lee•Allen Abram•Alex Rojas•Jun Kim