• Ei tuloksia

The capacitive electrostatic interface is a new technology. The information about the working of CEI is not well spread, but still some experts from the interview group were familiar with the technology. Even though the working of CEI remained largely unknown to many experts.

The only way to implement CEI is through the use of touch screen interface in the user interface devices in an elevator. Touch screen devices come with a fine and reliable haptic feedback mechanism. The touch screen device mostly utilizes vibration motors to generate a haptic feedback. If an example of any touch screen tablet device is taken, it can be observed that the device gives a haptic feedback without any delay.

Historically, due to the lack of ability to completely comply with the European standard EN 81-70:2008, touch screens have not been used in the UI devices of elevators. As argued by most of the experts the addition of a touch screen interface will improve the aesthetics of the UI devices. This will make the assembly process efficient, since a touch screen with CEI technology can be outsourced and assembled to the main level assembly upon delivery. With the modern-day touch interface devices, the IP code compatibility is achievable.

The use of touch screen with CEI will permit a design flexibility to the mechanical and software designers of the user interface devices. The use of CEI will make it possible to physically identify the activation area. The possibility to make the activation areas boundaries identifiable is not yet achievable with a touch screen interface. Another, short coming in using a touch screen interface equipped with CEI is that, even though the activation area is identifiable with a difference in the charge concentration but for a visually impaired person, the first contact with a UI device is aimed at finding the correct activation area through the brail system. It is not achievable to create the brail markings on a touch screen interface, as required by the European standard EN 81-70:2018.

Furthermore, in case of a touch screen interface with high sensitivity, the first touch initiates the activation signal. For an elderly person or a visually impaired person, the first touch to the UI device might not be intended for activation of the elevator system.

The modern-day touch screen devices are sleek in design and occupy less volume. The operational life of a touch screen in a UI device might not be predictable. The touch screen devices are more prone to vandalism as compared to the technologies discussed earlier in this thesis.

It was difficult to assess that how the use of touch screen devices equipped with CEI will affect the complexity of the user interface devices and the whole elevator system. The experts also agreed on the fact that since it has only been used in some test environments.

This still needs to be explored on how the use of CEI enable device tends to alter the elevator system.

6 DISCUSSION AND CONCLUSION

This chapter discusses the feasibility of the most suitable technology that can address research objective. The research was focused on the identification of a technology that can be used in the user interface devices of an elevator. The selection of the most feasible technology was partly dependent upon the capabilities of the technology to meet the European standard EN 81-70:2018 and partly on how the experts at KONE corporation view that technology based on their knowledge of the elevator environment and company standards.

The outcome of the research work was that, out of the four technologies that were expected to meet the European standard and expectations of the experts, piezoelectric devices were found to be the most suitable ones. The study demonstrates that the piezoelectric devices are most favored by the experts because of their qualities to meet the EN81-70:2018 code. The literature review depicts that the piezoelectric devices have in commercial use for well over three decades. The simplicity of the operating principal of piezoelectric devices make them a suitable component to be added to the UI devices.

Even though the CEI enabled touch screen would have been a much more modern and modular solution but the deficiency of this technology to meet the critical clauses of the EN 81-70:2018 makes it a less favorable technology. It was not anticipated that a CEI equipped touch screen devices will compliant with the EN 81-70:2018 at so many levels. Further research can be performed in finding out a solution that could enable a touch screen to be code compliant with EN81-70:2018 and more user friendly for visually impaired people.

With the introduction of the foldable touch displays it seems a highly possible scenario that the touch interfaces will be able to meet the requirements of European standards for use in user interface devices in elevators.

It can be argued that the results are based upon the opinion of the experts from KONE corporation. This limits the results to be considered for researchers outside of KONE corporation. Further, the research was limited to the scope of identifying a technology that can meet the requirements set by European standard EN 81-70:2018. Any other standards

that define the requirements for user interface devices have not been considered in this research work.

The research work concluded by answering both the research questions that are “What are the factors that influence the use of haptics in the user interface devices of an elevator?

What is the most suitable technology for obtaining haptic feedback in the UI devices in elevator?” The study of EN 81-70:2018 contained the factors that set the requirements to be met by a UI device and the literature review of each technology presented the capabilities and limitations. Both these information sources answered the first question by highlighting the factors that influence the use of each device in UI of an elevators. Further, the second question was answered with the selection of piezoelectric device as the most suitable for obtaining haptic feedback in UI devices as a possible replacement of traditional devices.

Conclusively, the outcome of the research is that piezoelectric devices are the capable solution to replace the traditional haptic feedback mechanisms in user interface devices. The piezoelectric devices exhibit the qualities that make them capable of meeting the EN 81-70:

2018 code. The results from the expert opinion built on the evidence from the literature review that piezoelectric devices can be used in the elevator environment, where the use is rigorous and require reliability and aesthetics at the same time. This research can be continued to establish a solution that could permit the use of piezoelectric devices in user interface devices of the elevator.

LIST OF REFERENCES

Bai, Y., Neveln, I., Peshkin, M. and MacIver, M. 2016. Enhanced detection performance in electrosense through capacitive sensing. Bioinspiration & Biomimetics, 11(5), p.055001.

Banter, B. 2010. Touch Screens and Touch Surfaces are Enriched by Haptic Force-Feedback. Information Display, 26(3), pp.26-30.

Baolong Electronic. 2019. Linear Resonant Actuator (LRA) | Baolong Electronic Group.

[online] Available at: https://www.vibrationmotors.com/vibration-motor-product-guide/linear-resonant-actuator/ [Accessed 30 Oct. 2019].

Blenkinsopp, R. 2019. What is haptic feedback? - Ultrahaptics. [online] Ultrahaptics.

Available at: https://www.ultrahaptics.com/news/blog/what-is-haptic-feedback/ [Accessed 4 Jul. 2019].

Carter, T., Seah, S., Long, B., Subramanian, S. and Drinkwater, B. 2013. UltraHaptics:

Multi-Point Mid-Air Haptic Feedback for Touch Surfaces. In: UIST '13 Proceedings of the 26th annual ACM symposium on User interface software and technology. St. Andrews, Scotland: Proceedings of the 26th annual ACM symposium on User interface software and technology, pp.505-514.

Chester, E. 2012. Senseg Technology Explained | Trusted Reviews. [online] Trusted Reviews. Available at: https://www.trustedreviews.com/news/senseg-feel-technology-explained-2910843 [Accessed 29 Jun. 2019].

E2e.ti.com. 2019. How does a linear resonant actuator work? - Analog - Technical articles -

TI E2E Community. [online] Available at:

https://e2e.ti.com/blogs_/b/analogwire/archive/2016/10/27/how-does-a-linear-resonant-actuator-work# [Accessed 24 Jul. 2019].

European standards 2018, Safety rules for the construction and installation of lifts - Particular applications for passenger and goods passenger lift - Part 70: Accessibility to lifts for persons including persons with disability, NEN-EN 81-70:2018, Royal Netherlands Standardization Institute, Netherlands.

Fictiv.com. 2019. Intro to Haptic Technology: Vibration Motors | Fictiv - Hardware Guide.

[online] Available at: https://www.fictiv.com/hwg/design/intro-to-haptic-technology-

vibration-motors#:~:targetText=Examples%20of%20ERM%20Vibration%20Motors,devices%20and

%20automotive%20touch%20screens. [Accessed 30 Sep. 2019].

Galitz, W. 2007. The essential guide to user interface design. Indianapolis, Ind.: Wiley, pp.4-Green, K., Champneys, A. and Lieven, N. (2006). Bifurcation analysis of an automatic dynamic balancing mechanism for eccentric rotors. Journal of Sound and Vibration, 291(3-5), pp.861-881.

Hayward, V., Astley, O., Cruz‐Hernandez, M., Grant, D. and Robles‐De‐La‐Torre, G. 2004.

Haptic interfaces and devices. Sensor Review, 24(1), pp.16-29.

Hélin, P., Sadaune, V. and Druon, C. 1998. Theoretical and experimental study of linear motors using surface acoustic waves. Sensors and Actuators A: Physical, 70(1-2), pp.67-74.

Hoggan, E. 2010. Crossmodal Audio and Tactile Interaction with Mobile Touchscreens. International Journal of Mobile Human Computer Interaction, 2(4), pp.29-44.

Hoggan, E., Brewster, S. and Johnston, J. 2008. Investigating the effectiveness of tactile feedback for mobile touchscreens. In: CHI '08 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems. Florence, Italy: ACM New York, NY, USA, pp.Pages 1573-1582.

kone, E. 2019. KONE Destination Solutions. [online] Eritrea.kone.com. Available at:

https://eritrea.kone.com/new-buildings/kone-people-flow-intelligence/elevator-destination-control.aspx [Accessed 7 Jun. 2019].

Linjama, J. and Mäkinen, V. 2009. E-Sense screen: Novel haptic display with Capacitive Electrosensory Interface. In: 4thWorkshop for Haptic and Audio Interaction Design.

Dresden, Germany.

Long, B., Seah, S., Carter, T. and Subramanian, S. 2014. Rendering volumetric haptic shapes in mid-air using ultrasound. ACM Transactions on Graphics, 33(6), pp.1-10.

Mclean, K. 2000. In: (ICRA’2000. Designing with Haptic Feedback: IEEE Robotics and Automation.

Moubarak, P., Ben-Tzvi, P. and Zaghloul, M. 2012. A Self-Calibrating Mathematical Model for the Direct Piezoelectric Effect of a New MEMS Tilt Sensor. IEEE Devices Journal, 12(5), pp.1033-1042.

Partovi Shabestari, N., Rashidian Vaziri, M., Bakhshandeh, M., Alidokht, I. and Alizadeh, Y. 2019. Fabrication of a simple and easy-to-make piezoelectric actuator and its use as phase shifter in digital speckle pattern interferometry. Journal of Optics, 48(2), pp.272-282.

Precisionmicrodrives.com. 2019a. Eccentric Rotating Mass Vibration Motors - ERMs -

Precision Microdrives. [online] Available at:

https://www.precisionmicrodrives.com/vibration-motors/eccentric-rotating-mass-vibration-motors-erms/ [Accessed 16 Sep. 2019].

Precisionmicrodrives.com. 2019b. Linear Resonant Actuators - LRAs - Precision Microdrives. [online] Available at: https://www.precisionmicrodrives.com/vibration-motors/linear-resonant-actuators-lras/ [Accessed 30 Sep. 2019].

Precisionmicrodrives.com. 2019c. AB-004 : Understanding ERM Vibration Motor Characteristics - Precision Microdrives. [online] Available at:

https://www.precisionmicrodrives.com/content/ab-004-understanding-erm-vibration-motor-characteristics/ [Accessed 30 Apr. 2019].

Precisionmicrodrives.com. 2019d . AB-004 : Understanding ERM Vibration Motor Characteristics - Precision Microdrives. [online] Available at:

https://www.precisionmicrodrives.com/content/ab-004-understanding-erm-vibration-motor-characteristics/ [Accessed 24 May 2019].

Robles-De-La-Torre, G. 2006. The Importance of the Sense of Touch in Virtual and Real Environments. IEEE Multimedia, 13(3), pp.24-30.

Sirohi, J. and Chopra, I. 2000. Fundamental Understanding of Piezoelectric Strain Devices. Journal of Intelligent Materials Systems and Structures, 11(4), pp.246-257.

Texus Instruments. 2019. [online] Available at:

http://www.ti.com/lit/ml/sszb151/sszb151.pdf [Accessed 30 Sep. 2019].

Ultrahaptics. 2019. Ultrahaptics - Discover a new type of haptics. [online] Available at:

https://www.ultrahaptics.com/applications/ [Accessed 27 Aug. 2019].

Vidal, F., John, N., Healey, A. and Gould, D. 2008. Simulation of ultrasound guided needle puncture using patient specific data with 3D textures and volume haptics. Computer Animation and Virtual Worlds, 19(2), pp.111-127.

Yamaguchi, T., Kawase, Y., Suzuki, S., Hirata, K., Ota, T. and Hasegawa, Y. 2008. Dynamic Analysis of Linear Resonant Actuator Driven by DC Motor Taking into Account Contact Resistance Between Brush and Commutator. IEEE Transactions on Magnetics, 44(6), pp.1510-1513.

Zhang, P. (2008). Industrial Control Technology. Burlington: Elsevier, pp.73-116.

ZHAO, H., LING, J. and YU, J. 2012. A comparative analysis of piezoelectric transducers for harvesting energy from asphalt pavement. Journal of the Ceramic Society of Japan, 120(1404), pp.317-323.

APPENDIX I, 1 This interview questionnaire is focused on getting the opinions and thoughts of the experts from the user interface category from KONE corporation. This questionnaire can be followed up by a face to face

interview.

The motivation behind this interview is to obtain industry oriented information and knowledge for haptic feedback technologies to achieve the objective of the research thesis as part of the project to

develop the metal touch keypad.

The thesis is being investigated by Atif Malik from LUT University.

You can reach Atif through:

Phone: +358 41 7504301 Email: atif.malik@kone.com

For the authenticity of information obtained through this questionnaire, following information is requested from you:

Your Designation at KONE Corporation:

Your area of speciality:

Contact Information(optional):

APPENDIX I, 2

Piezoelectric Sensors:

A piezoelectric sensor is a device that uses the piezoelectric effect, to measure changes in pressure, acceleration, temperature, strain, or force by converting them to an electrical charge.

The prefix piezo- is Greek for 'press' or 'squeeze'.

Please visit the below link for a short video example

of working of Piezoelectric sensor

https://www.youtube.com/watch?v=TgyMZA9fHFE

Based on your expertise please reply to these question:

YES NO UNSURE

My Remarks/

Thoughts/

Concerns I am familiar with the working of piezoelectric

sensors

I am familiar with some daily life applications of piezoelectric sensors

Piezoelectric sensors could give reliable media to provide haptic feedback to the user

A delay in the haptic response is expected

A compromise in the aesthetics would be needed to use piezoelectric sensors

An IP code compliance can be achieved in a product with Piezoelectric as source of feedback

A sufficient active area can be developed to receive a feedback

The active area can be made identifiable e.g. with engraved or protruding boundary

An operating feedback can be received by the user The feedback sensation is identifiable

The available space could be narrow for piezoelectric sensor

The system becomes complex by using piezoelectric sensors

The working quality can be better than the traditional solution

In my opinion, use of Piezoelectric sensors can yield following:

Benefits:

Drawbacks:

Limitations:

APPENDIX I, 3

Eccentric Rotating Mass (ERM)

The Eccentric Rotating Mass vibration motor, or ERM, also known as a pager motor is a DC motor with an offset (non-symmetric) mass attached to the shaft. As the ERM rotates, the centripetal force of the offset mass is asymmetric, resulting in a net centrifugal force, and this causes a displacement of the motor.

Please visit the below link for a short video example

of working of ERM

https://www.youtube.com/watch?v=jvCSh5fgTZI

Based on your expertise please reply to these question:

YES NO UNSURE

My Remarks/

Thoughts/

Concerns I am familiar with the working of ERM

I am familiar with some daily life applications of ERM

ERM could be a reliable media to provide haptic feedback to the user

A delay in the haptic response is expected

A compromise in the aesthetics would be needed to use ERM

An IP code compliance can be achieved in a product with ERM as source of feedback

A sufficient active area can be developed to receive a feedback

The active area can be made identifiable e.g. with engraved or protruding boundary

An operating feedback can be received by the user The feedback sensation is identifiable

The available space could be narrow for ERM The system becomes complex by using ERM

The working quality can be better than the traditional solution

In my opinion, use of ERM can yield following:

Benefits:

Drawbacks:

Limitations:

APPENDIX I, 4

Linear Resonance Actuator (LRA)

A linear resonant actuator is a precision vibration motor that produces an oscillating force across a single axis. Unlike a DC eccentric rotating mass (ERM) motor, a linear vibration motor relies on an AC voltage to drive a voice coil pressed against a moving mass that is connected to a spring.

Please visit the below link for a short video example

of working of LRA

https://www.youtube.com/watch?v=ge_7qfv2c2Y

Based on your expertise please reply to these question:

YES NO UNSURE

My Remarks/

Thoughts/

Concerns I am familiar with the working of LRA

I am familiar with some daily life applications of LRA LRA could be a reliable media to provide haptic

feedback to the user

A delay in the haptic response is expected

A compromise in the aesthetics would be needed to use LRA

An IP code compliance can be achieved in a product with LRA as source of feedback

A sufficient active area can be developed to receive a feedback

The active area can be made identifiable e.g. with engraved or protruding boundary

An operating feedback can be received by the user The feedback sensation is identifiable

The available space could be narrow for LRA The system becomes complex by using LRA In my opinion, use of LRA can yield following:

Benefits:

Drawbacks:

Limitations:

APPENDIX I, 5

Capacitive Electrosensory Interface

Senseg is a Finnish start-up which is the pioneer of making touch screen with texture feeling with their iconic product "FeelScreen". It gives haptic feedback through LRA or ERM and also the texture on the

screen can be felt with the hand.

Please visit the below link for a short video example

of working of FeelScreen by Senseg

https://www.youtube.com/watch?v=eiOe64RPTwo https://www.youtube.com/watch?v=FiCqlYKRlAA

Based on your expertise please reply to these question:

YES NO UNSURE

My Remarks/

Thoughts/

Concerns I am familiar with the working of Senseg touch

Screen

I am familiar with some daily life applications of Senseg touch Screen

Senseg touch Screen could be a reliable media to provide haptic feedback to the user

A delay in the haptic response is expected

A compromise in the aesthstics would be needed to use Senseg touch Screen

An IP code complaince can be achieved in a product with Senseg touch Screen as source of feedback A sufficient active area can be developed to receive a feedback

The active area can be made identifiable e.g. with engraved or protuding boundary

An operating feedback can be received by the user The feedback sensation is identifiable

The available space could be narrow for Senseg touch Screen

The system becomes complex by using Senseg Touch Screen

In my opinion, use of Senseg touch Screen can yield following:

Benefits:

Drawbacks:

Limitations: