Sony Car Stereo Redesign

Sony Car Stereo Redesign CS 6021 Foundations of Interactive Media Tuan Foley 0426806 Brian O’Callaghan 0508713
Table of Contents 1. Introduction....................................................................................................................4 1.1 Sony MEX-­‐1HD ....................................................................................................................................... 4 2. Usability Evaluation .....................................................................................................5 2.1 Definition of Heuristic Evaluation ............................................................................................ 5 2.2 Findings from Usability Heuristics........................................................................................... 5 2.3 Visibility of system status ............................................................................................................ 6 2.4 Match between system and the real world .......................................................................... 7 2.5 User control and freedom ............................................................................................................ 7 2.6 Consistency and standards.......................................................................................................... 8 2.7 Error prevention .............................................................................................................................. 9 2.8 Recognition rather than recall .................................................................................................10 2.9 Flexibility and efficiency of use ...............................................................................................10 2.10 Aesthetic and minimalist design ..........................................................................................11 2.11 Help users recognize, diagnose, and recover from errors ........................................11 2.12 Help and documentation .........................................................................................................12 3. Cooperative Evaluation............................................................................................ 13 3.1 The Task List....................................................................................................................................13 3.1.1 The Tasks.......................................................................................................................................13 3.2 Recruiting the Users .....................................................................................................................14 3.3 Preparing the tasks for the users............................................................................................15 3.4 Performing the tasks ....................................................................................................................15 3.5 Findings from Cognitive Evaluation ......................................................................................22 4.0 Prototype.................................................................................................................... 24 4.1 Requirements for prototype ..........................................................................................................24 4.2 Specific Prototype Features............................................................................................................25 4.2.1 Turning System on and off .....................................................................................................25 4.2.2 Choosing an Audio source ......................................................................................................25 4.2.3 Choosing radio presets ............................................................................................................26 4.2.4 Programming a new station ..................................................................................................26 4.2.5 CD loading...........................................................................................................................................27 4.2.6 Feedback........................................................................................................................................27 2 4.2.7 The Touch Screen.......................................................................................................................28 4.2.8 EQ settings ....................................................................................................................................28 5. Conclusion .................................................................................................................... 30 6. Appendices ................................................................................................................... 31 7. Bibliography ................................................................................................................ 36 3 1. Introduction The purpose of this report was to evaluate a Sony car stereo head unit from a usability point of view, and produce a medium fidelity prototype from the evaluation. This prototype was then tested and the results analyzed, and new recommendations drawn up for the next step of the design process. We chose a high-­‐end car stereo produced by Sony, the MEX-­‐1HD. The unit was evaluated Heuristically, and a task list was compiled to assist both the construction of a prototype and to direct the user testing which was carried out. We chose a car stereo as we felt this was an area in which the user centered design process was often neglected in an effort to cram as many features as possible into a product. This system, the MEX-­‐1HD was found to be a particularly difficult one to operate from a drivers point of view and the evaluation highlighted several major flaws which needed to be ironed out. 1.1 Sony MEX-­‐1HD
The MEX-­‐1HD is a single DIN (180 x 50 mm panel) head unit sold as an aftermarket replacement for a standard audio system sold with a car, capable of output via FM radio, AM radio, compact disk, from a built in Hard Drive, and from an Auxiliary input. The display is a 75mm x 25mm dot-­‐matrix single colour LED screen displaying a bluish-­‐green text. 4 2. Usability Evaluation To discover the usability issues with the Sony stereo, we decided to follow the techniques developed by Jakob Nielson. These techniques are an expert’s guide to a set of usability principles known as heuristics. It is an inexpensive usability engineering method. Jacob Nielson has developed ten methods of determining an artifacts usability issues. Most of these will be discussed later in the chapter in relation to the Sony Car Stereo. 2.1 Definition of Heuristic Evaluation Heuristic evaluation is the most popular of the usability inspection methods. Heuristic evaluation is done as a systematic inspection of a user interface design for usability. The goal of a heuristic evaluation is to find the usability problems in the design so that they can be attended to as part of an iterative design process. It is used to help find problems within the system. In other words how the user is able to navigate within the system to do their selected tasks. 2.2 Findings from Usability Heuristics The focal point of this exercise is to establish ways of making the Sony Stereo more user friendly and safer to use while driving. For this reason the evaluators are not concentrating on all functions of the user interface (UI). As there are only two members in the group, the Heuristic Evaluation was done together. 5 2.3 Visibility of system status The system should always keep users informed about what is going on, Through appropriate feedback within reasonable time. The main form of feedback is the LED screen (25mm x 75mm). The display changes with different functions. The buttons also make a sound when pressed notifying the user of its completion. Figure 2.1
Both evaluators felt that the screen was an adequate size but could be a lot bigger. A driver can only permit a quick glance at the stereo while driving. Also there are a lot of functions such as the time, track number and bass shown on the screen at all times which is confusing and hard to navigate around especially with only one text colour. 6 2.4 Match between system and the real world The system should speak the users' language, with words, phrases and Concepts familiar to the user, rather than system-­‐oriented terms. Follow real world Conventions, making information appear in a natural and logical order. Some of the buttons are complicated. Three of the buttons on the right of the LED screen have no text on them. Also the source button is used to change from CD/Radio/Hdd and AUX. It also is the on button for the stereo but does not turn it off. Most of the functions are done through the LED screen. As you can see below the buttons represent REP,SHUF and the return symbol. These three buttons change functionality depending on what audio source the user has on. There is also a separate “off” button on the on the bottom of the stereo with only one function. The two large knobs on either side of the stereo do function well. Figure 2.2 Figure 2.3 2.5 User control and freedom Users often choose system functions by mistake and will need a clearly marked "emergency exit" to leave the unwanted state without having to go through an extended dialogue. Support undo and redo. 7 There is an error prevention or “emergency exit” located on the screen which is
accessed by the function buttons on the LED. There is an example below of the
symbol which appears on the screen. Or you can just press the “off” button allowing
you to start over again.
Figure 2.4 2.6 Consistency and standards Users should not have to wonder whether different words, situations, or actions mean the same thing. Follow platform conventions. Once again the source button has caused confusion as it also is the “on” button. It is also hard to tell which audio source is been used as they all appear very similar on the LED screen. There is very little difference on the screen between radio, CD and HDD(hard drive). The audio settings such as balance, fade, base and treble are hard to find. The evaluators believe a separate button should be used. The other buttons such as menu and function are displayed with the letters M and F. Figure 2.5
8 2.7 Error prevention Even better than good error messages is a careful design that prevents a problem from occurring in the first place. Either eliminate error-­‐prone conditions or check for them and present users with a confirmation option before they commit to the action. There are design problems related to the placement of some of the buttons on the stereo. For example the “OPEN” and “CD eject” button are very close together. The “OPEN” button allows you to access the usb connection, CD and HDD while the “CD eject” does pretty much the same function. The only difference is that the CD tray will eject. The evaluators believe that there is no need for two buttons situated together that perform almost the same task. Figure 2.6 The “OFF” button has to be held down for four seconds for the system to totally switch off. It is a long time to be taking your hand off the steering wheel if you want to turn off the system. There are a total of fourteen buttons on the Stereo front. Some of these buttons share some of the same or similar functions. The toggle is complicated and takes time to find functions. It could be hazardous when driving. 9 2.8 Recognition rather than recall Minimize the user's memory load by making objects, actions, and options visible. The user should not have to remember information from one part of the dialogue to another. Instructions for use of the system should be visible or easily retrievable whenever appropriate. The Radio function only gives the frequency of the radio station instead of the name. The Stereo has a very complicated method of storing stations through the menu system using the right knob. It would be unsafe to navigate through while driving. The sound menu is equally hard to modify. The screen does not have a light meter because of this it always appears dull and hard to see. 2.9 Flexibility and efficiency of use Accelerators -­‐-­‐ unseen by the novice user -­‐-­‐ may often speed up the interaction for the expert user such that the system can cater to both inexperienced and experienced users. Allow users to tailor frequent actions. The Sony Stereo has a shortcut for automatically saving all radio stations over the entire frequency band. This does not work efficiently as it saves the same radio station over and over on different frequencies. For example 2fm would be saved on two different frequencies such as 90.6 and 91.0. There is no shortcut for saving radio stations, which the evaluators see as a must for the redesign. As there are not a lot of buttons on the system, the menu is accessed using the knob on the right. This makes it difficult to concentrate on especially while driving. 10 2.10 Aesthetic and minimalist design Dialogues should not contain information that is irrelevant or rarely needed. Every extra unit of information in a dialogue competes with the relevant units of information and diminishes their relative visibility. Figure 2.7 Actual Stereo used in evaluation
The design of the MEX-­‐1HD Sony Stereo is minimalist. The few buttons add to the aesthetics of the design but take away from its ease of use. The CD deck, usb connection and the hard drive are all hidden behind the stereo. The front of the part moves out and downwards when either the “CD eject” or “OPEN” button are pressed this is one of the features the evaluators would like to keep. 2.11 Help users recognize, diagnose, and recover from errors Error messages should be expressed in plain language (no codes), precisely indicate the problem, and constructively suggest a solution. The Sony Stereo comes with a well illustrated and documented book (125 pages). You can simply jump to the area or the piece of information you need as the book is well indexed and contains good content. As there are only 4 main functions associated with this stereo, not many errors can occur. 11 2.12 Help and documentation Even though it is better if the system can be used without documentation, it may be necessary to provide help and documentation. Any such information should be easy to search, focused on the user's task, list concrete steps to be carried out, and not be too large. If a problem does occur an error message should appear. The manual has a troubleshooting section which gives references to most of these issues. The manual is very well documented and users are encouraged to refer to it before calling or emailing online support. 12 3. Cooperative Evaluation A cooperative evaluation is a great way of obtaining data about the issues and problems at the early stage of the prototype development (it is mainly used at the early stages but can be used at any stage). Users are recruited and encouraged to quiz the designer on elements of the prototype. There are four main steps involved in the cooperative evaluation: 1, recruiting the users 2, preparing the tasks for the users 3, interacting and recording the users experience and 4, summarizing all the observations made. 3.1 The Task List We made up the task list with the first evaluation in mind (pre heuristic evaluation). We discussed what we wanted to change from the original Stereo and see if the new design met our needs. The heuristic evaluation pointed out more areas we needed to explore in the task list and design. We also only focus on radio and CD functions as the HDD is very similar and the AUX is basically plugging an external audio device such as a Zen or iPod. There are seven tasks each with one or two functions. 3.1.1 The Tasks 1. Turn on the system and select one of the following options: CD/Radio/HDD or AUX. 2. Choose a radio function and select 2fm, a preset station. 3. Program a new radio station in automatic mode (automatic mode is where the device will find the nearest working station). 13 4. Return to the audio options and select CD. (Audio options is the home screen which gives you an option between CD/Radio/HDD or AUX). 5. While in the CD function select CD 4 and the 4th track on that CD. Then repeat that song. 6. Replay all tracks on CD 4. 7. Finally go to the sound adjustment menu and show how you would change the fade, balance and bass. 3.2 Recruiting the Users We recruited four people between the ages of 23 and 40, three men and one woman. One of the users was familiar with Sony Stereo’s but not the MEX-­‐1HD. Two of the members are students and the other two are working. The Evaluators felt that people between these ages would be the prime targets for Sony. USER Experience of Sony AGE Gender Stereo’s A No 23 Male B No 23 Female C No 26 Male D Yes 40 Male Figure 3.1 14 3.3 Preparing the tasks for the users To make the Prototype more realistic to the user we used an LCD a touch screen monitor which we connected to a computer. We also designed the stereo as a HTML website (on Dreamweaver) so when the user pressed a button on the LCD it would automatically bring them to a new page showing the desired result. The tasks evaluation took place in one of the evaluator’s homes. It was recorded using a handheld Canon digital camera. All users were asked if they felt comfortable in front of the camera. One of the Evaluators read out and went through the task list with the user while the other took notes. Continuous interaction was held throughout the tasks and the user was encouraged to talk about how they went about the tasks. Everything was kept very light hearted to put the user at ease and to simulate a real life scenario. After each user was finished all the tasks, we asked them about the prototype. The parts the liked and dislike and what they would change. The camera kept recording until user left. 3.4 Performing the tasks USER 1 1. How do you turn on the system and select one of the following options: CD/Radio/HDD or AUX User 1 instantly identified the power button located in the bottom left of the radio. He then selected CD 2. Choose a radio function and select 2fm User 1 selected the first option from the touch screen display with the radio waves symbol and then pressed the number two button on the bottom of the stereo. 15 3. Program a new radio station in automatic mode (automatic mode is where the device will find the nearest working station) User 1 tried to tune the station in with the right rotating knob first and then realized the search button is located on the screen. Once the desired frequency was found, user 1 held number 2 of the 6 numbered buttons for less than one second. The user left the Auto seek button on not opting for manual search. 4. Return to the audio options and select CD. (Audio options is the home screen which gives you an option between CD/Radio/HDD or AUX) User 1 did not find the audio source button and ended up turning the radio off and on again to get to the Audio option menu. Then the user selected the second option with the CD logo 5. While in the CD function select CD 4 and the 4th track on that CD. Then repeat that song The user quickly realized that the 1-­‐6 buttons on the bottom of the stereo were the compact disk selection. Then the user pressed the fast forward button on the right side of the play button (till the forth track appeared on display) to complete the task. 6. Replay all tracks on CD 4 The user instantly selected the touch screen button “repeat all” 7. Finally go to the sound adjustment menu and show how you would change the fade, balance and bass. The user selected the “sound menu” button and was able to adjust the bass without any problems. The user was unsure of the balance and fade car display. The designer explained how to use it 16 Review of User 1 User 1 liked the touch screen display and suggested that the designers should make all functions on the radio touch screen. The menu has been simplified down and is much easier to navigate through the four main functions of the Stereo. The user noticed that there was no time displayed on the radio and suggested we should add it.
17 USER 2 1. How do you turn on the system and select one of the following options: CD/Radio/HDD or AUX User 2 selected the power button and pressed CD on the display screen 2.Choose a radio function and select 2fm User 2 selected the first option from the touch screen display with the radio waves symbol then selected the button 2 underneath the 2fm RDS display 3. Program a new radio station in automatic mode (automatic mode is where the device will find the nearest working station ) User 2 selected the automatic mode button and then the search button. When the search had stopped the user held number 6 button down for 3 seconds 4. Return to the audio options and select CD. (Audio options is the home screen which gives you an option between CD/Radio/HDD or AUX) This user had knowledge of Sony stereo’s and selected the “audio Source" button instantly. 5. While in the CD function select CD 4 and the 4th track on that CD. Then repeat that song The user knew that the 1-­‐6 buttons on the bottom of the stereo were the compact disk selection. Then the user pressed the fast forward button multiple times on the right side of the play button (untill the forth track appeared on display) to complete the task. 6. Replay all tracks on CD 4 The user instantly selected the touch screen button “repeat all” 18 Finally go to the sound adjustment menu and show how you would change the fade, balance and bass. The user selected the sound menu and was able to use all the touch screen functions by selecting them and using the knob on the right to adjust the settings. The user was also able to explain how he felt the balance and fade display would work. Review of User 2 User 2 had previous experience with a Sony stereo and liked the new changes as it simplified the functions and the new sound menu. The user did ask if the screen would remain bright all the time as it could put off the driver. User 2 had no negative remarks. USER 3 1. how do you turn on the system and select one of the following options: CD/Radio/HDD or AUX User 3 selected the power button and selected CD 2. Choose a radio function and select 2fm User 3 selected the first option from the touch screen. It took over 30 seconds for 19 the user to figure out how to select 2fm. 3. Program a new radio station in automatic mode (automatic mode is where the device will find the nearest working station ) User 3 selected both the volume and function knobs on each side of the stereo in order to adjust the station. After a while one of the designers pressed the touch screen seek button to show the user how to change the frequency. Once the desired channel was selected, the user held the number 1 button down for one second to preset the station. 4. Return to the audio options and select CD. (Audio options is the home screen which gives you an option between CD/Radio/HDD or AUX) User 3 like user 1 also turned off the stereo via the power button and turned it back on to get to the audio options 5.While in the CD function select CD 4 and the 4th track on that CD. Then repeat that song The user selected the CD option with no difficulty and with a bit of help from the designer selected number 4 button on the bottom of the stereo. The user replayed song without difficulty 6. Replay all tracks on CD 4 User 3 first selected replay 1t but then selected repeat all on the touch screen display. 7. Finally go to the sound adjustment menu and show how you would change the fade, balance and bass. User 3 selected the sound menu button and used the touch screen vertical bar to change the settings of bass. But did not understand car display for fade and balance until it was explained by the designer 20 Review of User 3 User 3 liked how the stereo looked and thought that the change in colors was a nice touch for each of the four functions. The user stressed that she was not used to using touch screen and felt that with some time using the radio that she would be much better. USER 4 1 .How do you turn on the system and select one of the following options: CD/Radio/HDD or AUX User 4 instantly selected the power button. And selected the radio option. 2. Choose a radio function and select 2fm User 4 was already on the radio option from task 1. He then selected the number 2 which successfully tuned in 2fm 3. Program a new radio station in automatic mode (automatic mode is where the device will find the nearest working station ) User 4 selected the seek forward button and tuned in a new station by pressing the preset button 6 for at least 2 seconds. 4. Return to the audio options and select CD. (Audio options is the home screen which gives you an option between CD/Radio/HDD or AUX) User 4 asked where the back button was and then saw the audio source button and successfully returned to the audio options menu 5. While in the CD function select CD 4 and the 4th track on that CD. Then repeat that song The user selected the CD option and CD 4 via the number 4 button on the bottom 21 of the stereo. user 4 had no problem selecting the repeat 1 button 6. Replay all tracks on CD 4 User 4 selected the repeat all button instantly 7. Finally go to the sound adjustment menu and show how you would change the fade, balance and bass. User 4 selected the sound menu button and used the touch screen vertical bar to change the settings of bass. The user figured out how to change the balance and fade car display after trying the rotating knobs first. Review of User 4 User 4 liked the design of the stereo and the fact that not everything was touch screen. His reason for this is that when he drives he rarely even looks down at the stereo and uses touch to find volume and different audio sources. 3.5 Findings from Cognitive Evaluation Overall the designers were happy with the feedback from the four users. Most of the tasks worked without serious issues. The users were able to complete the tasks in a relatively short time, and with more experience would become proficient at using the system. The task involving selecting the audio source (task 4) provided an obstacle to the users. Close consideration will have to be given when re-­‐designing the next iteration of the prototype. Ideas such as a ‘Home’ button or a ‘return’ button on the touch screen will need to be looked at. The lack of a clock on the prototype was pointed out by one user, and a clock should be implemented in the next iteration. The equalizer adjustment screen gave a graphical representation of a car to allow for balance and face adjustment. Users mover their finger around the car graphic to 22 adjustment. Users complained this was not intuitive at first, but once shown agreed that it was an easy way to adjust these settings. Overall there was little negative feedback, but it is felt that a wider selection of users would be beneficial for the evaluation. 23 4.0 Prototype Figure 4.1 4.1 Requirements for prototype Using prototypes in the design process allows the designer to evaluate an iteration of a design, and recommend changes for the next iteration, with the end goal being every possible problem or shortcoming being ironed out by the final iteration. For the purpose of this project, the group compiled a list of design requirements from an Heuristic evaluation of the stereo, and implemented these requirements in a medium fidelity prototype, which was used for user testing. The main areas to be covered by the prototype included: •
The system needed to be easier to operate from a drivers point of view. •
Redesign the layout and labeling on the buttons to avoid confusion and duplication. •
Implement a touch screen to the face, making controlling the system more intuitive. •
Some features worked well and it was decided to keep these in the prototype. 24 4.2 Specific Prototype Features 4.2.1 Turning System on and off It was unclear how to switch the system on or off. The system was turned on by depressing the ‘source’ button, and turned off by depressing the ‘off’ button for four seconds. It could be put into standby by depressing the ‘off’ button for less than four seconds. The complete lack of an Figure 4.2 ‘on’ or ‘power’ button, and the presence of an ‘off’ button leads to instant confusion. The user will already know how to turn the system off before knowing how to turn it on. The prototype dispensed with both buttons, introducing a universally recognized ‘power’ button to turn the system ‘on’ and ‘off’ more easily. 4.2.2 Choosing an Audio source Figure 4.3 The original system relied on the source button to both turn the system on and also to select which output the user desired. The user could cycle through outputs by repeatedly depressing the source button after turning the system on. The prototype re-­‐labeled the ‘source’ button to ‘audio source’, and once depressed, presented the user with a selection on the touch screen. The user then selected the preferred output by touching the screen.
Figure 4.4 25 4.2.3 Choosing radio presets Pre-­‐programmed stations were selected by depressing the right side jog-­‐dial and scrolling it to the desired station, then depressing it again to switch to the station. Rotating the dial would scroll one-­‐by-­‐one through the presets. The prototype introduced six new numbered buttons below the screen which could select the presets. Figure 4.4 The preset name was displayed on the screen which was also sensitive to touch to change station. 4.2.4 Programming a new station Programming a new preset on the original system was very difficult. Switching between auto and manual seek could only be done via the menu system, requiring 3 levels of menus to switch. Once a station could be located, the user had to enter the menu system again and manually enter the preset. After this a name could be manually input. The prototype has been fitted with Radio Data System (RDS), which automatically picks up a stations name, and maintains the best reception for those stations which broadcast over several frequencies. Seeking could be done manually or automatically without entering the tiered menu system, and a preset saved by holding down one of the preset buttons for 2 seconds. Figure 4.5 26 4.2.5 CD loading The original system lacked a clear intuitive way to open the CD tray. On the face of the unit, there was an ‘open’ button, a CD ’eject’ symbol on a different button, a ‘release’ button, and the word ‘close’ written on the face near one of the buttons. There was also a duplicate ‘eject’ button behind the face. This lead to confusion for users, as all of these could be associated with similar actions. The prototype did away with the ‘close’ text, and the ‘CD eject’ symbol leaving only a larger ‘open’ button. The duplicate ‘CD eject’ button was left behind the face, visible once the open button is depressed. The prototype also allows up to 6 CDs to be loaded into Figure 6.6 Figure 4.7 the unit, with the user selecting which CD to eject by ejecting which ever CD is activated, indicated by the numbered button changing colour. 4.2.6 Feedback The original system used audio feedback when pressing the buttons. The prototype introduced a vibrating pulse whenever a button or hotspot on the touch screen was pressed. 27 4.2.7 The Touch Screen The original system was of a minimalist design, which also impeded the ease of use. The idea of using a touch screen on a stereo face allows Sony to keep the minimalist design while increasing the functionality of the system without cluttering the face with several buttons. 4.2.8 EQ settings To adjust the equalizer settings on the original system, the left dial needed to be pressed to open the sound menu, and then rotated through several options to adjust the sound. There was little indication that the dial controlled the sound settings, as it already controlled the volume. The prototype introduced a ‘sound menu’ button which brought up a new menu on the touch screen, and the user adjusted the sound via this touch screen. Figure 4.8 28 29 5. Conclusion The objective of this project was to produce a prototype of a car stereo from the point of view of the driver, making operation as simple as possible. The main aspects of the original system we wanted to keep were the aesthetics and functionality, while those we sought to remove were the unintuitive methods through which the system was operated. Having analyzed the heuristic and co-­‐operative evaluations it became apparent us that we have to focus our design more for the user, and less on how we feel it should be. Greater research into the human factors, and a greater understanding of who will actually use the system would benefit this. The prototype using a touch screen helped greatly in securing accurate user tests, as opposed to the users having to use a mouse on the screen. The project was a good practical example of the implementation of the skills and techniques learned during the module. As a group we are happy with the outcome of the project and prototype, and have learned much on how to approach the design process. 30 6. Appendices
31 32 33 34 35 7. Bibliography Ciolfi, Luigina, Lecture Notes, Foundations of Interactive Media, CS6021. Monk, Wright, Haber and Davenport, (1993), Cooperative Evaluation runtime guide. p 365 -­‐368 of “Interaction Design”
Norman, Donald A., (2002). The Design of Everyday Things. New York: Basic Books. p157-­‐203
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