Introduction to HMI Display

HMI is one of the display forms of human-computer interaction, and it is a specific term for the information interaction between people and cars. The design of HMI is to bring good experience to the interaction between people and cars. What is HMI? How can HMI designers effectively improve the interactive experience between people and cars? In this paper, the author analyzes the concept of HMI, summarizes the characteristics of the vehicle system, and combs the development of the vehicle system, to share the relevant knowledge of HMI design with you ~

First, what is the car HMI?

1. Basic concepts of HMI

Many students who want to be involved in HMI design are UI and UX designers. Therefore, in order to have a more comprehensive understanding of HMI, I will make a horizontal comparison between HMI and UX and UI

UI: indicates the User interface. Users interact with each other and complete the operation through the screen guidance of the product.
UX: indicates User experience. It refers to the user’s experience of the whole product interaction in the process of using the product.
HMI: Human-Machine Interaction, that is, the information interaction between people and vehicles. It brings information interaction between the car and the user when the car is driving.
The interaction information between people and cars can be transmitted through many channels, such as large screen, switch, button, voice system, etc. These channels help drivers complete the driving task together, but also bring drivers a good use experience. The dimensions of good user experience are also different, such as smooth interaction, timely feedback and efficient information transmission.

2. Application scenarios and carriers of HMI

After understanding the concepts of HMI, what are the requirements of HMI users? What are the usage scenarios for HMI? Through what carrier to present?

HMI user needs: The characteristics of large products of automobiles determine the attributes of low frequency consumption. Besides assisting drivers to complete driving tasks, the most important thing of automobiles is the guarantee of safety and stability, so HMI also needs to be integrated into the inherent genes of these automobiles.
HMI usage scenario: on-board HMI is the interaction between people and cars in the in-car scenario. Due to the structural design of vehicles and the behavior needs of drivers, drivers usually use their right hands for interactive operations.
HMI display carrier: center control large screen, switch, button, dashboard, front passenger display, rear display, etc. Here are some of the more common HMI carriers

(1) Central control screen: the central control screen of the car can control a part of the vehicle’s facilities and connect the reversing image and other functions. Driving entertainment and driving pleasure also have an increasingly close dependency relationship with the drivers. In the future, the on-board display will be connected with more cross-era technology.
(2) Instrument panel: now the pure liquid crystal instrument panel has replaced the traditional instrument panel and become the mainstream trend. The traditional instrument panel includes: pure machinery, light display, segment code, etc.
(3) Rear seat display: the rear seat display has strong entertainment properties, mainly with video, music, games, weather forecast and other functions. It can be exchanged according to the different needs of rear seat passengers, which is an effective way to optimize the riding experience of rear seat passengers.

3. HMI market and prospect development

The following from the industry direction, policy, consumer these three dimensions to analyze the HMI market and development prospects ~

Industry Direction: The future of HMI need not be overstated. With the world’s top Internet companies flooding into the car circuit, the future of HMI industry is self-evident. From the international top Internet companies Google Android auto, Apple CarPlay, and then to the domestic top companies Huawei Car application, Baidu’s Car Life and Apollo, Ali’s zebra, Tencent’s Ai in Car have entered the board;
Policies: The government attaches great importance to the development of automobile informatization and intelligence, and focuses on supporting the development of such high-tech industries;
Consumer market: Consumers are paying more and more attention to the driving experience of cars. Whether HMI matches with the accessories in the car is also an important reference condition, and these have also become the key factors affecting whether the vehicle is sold, so the user experience is also an important reference basis for automobile design factories.
After the introduction, I believe that we are optimistic about the development and prospects of this industry, there will be more designers to share the dividend of HMI development, will want to further understand HMI ~

Second, HMI design concept

The user experience system of HMI is set based on the relationship between people and cars, which is composed of four systems: safety, efficiency, comfort and experience from top to bottom. The design of HMI can exert a positive effect on these systems.

1. HMI design principles

What are the design principles of HMI? It has a close connection with UI/UX, and the design principles of HMI are different from other design areas based on the special attributes and usage scenarios of HMI.

(1) Light operation: In the specific scenario of human-vehicle interaction, drivers usually use their left hand to carry out the basic operation required by driving, and their right hand to carry out the interactive operation of HMI system and perform multiple operation tasks at the same time. There are risks to the safety of vehicles in the non-stationary state under multi-task simultaneously. Therefore, HMI should firstly ensure the safety of drivers and carry out information interaction design, so that drivers can easily complete the operation of HMI system in the process of driving.
(2) Efficient browsing: with the continuous enrichment of people’s lives, motorists have increasingly higher requirements for comprehensive functions of HMI, and more functions and information are required for the “large-screen” HMI system. Therefore, in the design of HMI, it is very important to bring more efficient information browsing efficiency to drivers. It is necessary to refine the information to ensure that the information is easy to understand, accurate and clear, so as to support the efficient browsing of drivers.
When setting the information level, the driver can capture the most critical information more quickly, which can be achieved through comparative design skills, so as to ensure that the driver can also have efficient browsing while driving the vehicle and reduce the driver’s visual capture cost.
(3) Immediate feedback: In actual driving scenario, road conditions, route, signal is very complex, the changes of the driver takes higher energy costs, so the information interaction with the HMI, to achieve rapid feedback, can through the ways such as vision, touch, speech and timely feedback, so on the design of the HMI is also should pay attention to the efficiency of information transfer.

2. HMI design features

Just introduced the design principles of HMI, so based on the above three design principles, what are the design characteristics of HMI design?

(1) Usage scenario: The design principle of HMI is generated based on the special usage scenario of HMI. HMI is located in the middle area of the front cockpit, on the right side of the main driver’s seat. The distance between the eyes and the screen is 50-60cm, so the driver needs to view the contents on the screen by squinty during the driving task. Such scenarios need to consider the differences in HMI design, such as hardware screen size, software font size, graphics, ICONS, colors, etc.
(2) Brand perception: As the scale of automobile enterprises in the automobile market continues to expand, the head automobile enterprises pay more and more attention to the differentiated design of the brand, and leave users with a deeper impression through the unique brand. Today’s users like a stylish interior with a sense of quality, and a good HMI design is not the core factor in buying a car, but it is a must. With the emergence of more and more models of the same car company, the user portrait of each model is gradually refined, because the more need for HMI customization, from style design to brand perception, to locate the precise user image group to match it.
(3) User experience: HMI interaction behavior is relatively fixed, but the interaction mode is a combination of many kinds: voice, touch, button, button. The interaction between these modes is a relatively high frequency operation. Combined with the use scenario of HMI, HMI is required to have a low fault tolerance rate, and at the same time, the problem of the actual operation hot zone should be considered.

3. HMI interaction concept

Next, I will introduce the interactive concepts of HMI in detail, and introduce them from the interactive mode, interactive mode, interactive copy and interactive feedback of HMI

1)Interactive mode

The interaction mode of HMI is a comprehensive mode of interaction through feedback information provided by various sensory channels, including sensory participation in vision, hearing, touch, smell and taste. The participation of these senses should be obtained through corresponding human organs, such as eye, nose, mouth, ear and hand, etc. The design of HMI is also designed around these senses, and in more application scenarios, the joint cooperation between various senses is needed, so HMI is also called multi-sensory interaction mode.

This comprehensive interaction mode of multi-sensory sharing can make the interaction behavior in the car more relaxed, increase the interest of interaction, and no longer need to repeat the mechanical interaction.

2)Interaction mode

There are many common interaction methods: hardware keys, soft touch, voice, gesture, etc., here is a detailed introduction to the four common interaction methods ~
(1) Button interaction: The interaction form of buttons has a long history and is composed of hardware parts, usually including buttons and buttons. Buttons are indicated by simple ICONS, while buttons are indicated by operating methods with strong directivity. Drivers have long been used to this kind of interaction.

(2) Touch interaction: The large screen of the central controller is the most common part of touch interaction. The emergence of the large screen of the central controller also brings great changes to HMI interaction. Touch interaction includes: Click, double-click, long press, slide, drag and drop one hand, both hands drag-and-drop, etc., but in addition to click other ways are easily exceeds the scope of the safety time of 2 seconds, such operations in the process of complex driving appear too tedious, that affect driving safety, therefore, the driver in the process of driving tasks, Clicking is the most common and relatively inexpensive way to interact.

So what kind of interaction should be applied in which scenarios? Next we will bring you full of dry goods, please code live ~
Click: button, icon, tab switch, check box, control, etc.;
Double click: enlarge the picture, navigate the map;
Long press: select and edit;
Slide: home function card, negative screen, list, air conditioning wind direction, temperature, progress bar (volume, brightness, video, music, radio, etc.);
One-hand drag: select and edit to change the position;
Two-handed drag and drop: zoom in, navigate the map.
(3) Voice interaction: Voice interaction can effectively reduce the cost of users, in the driving operation, can disperse the minimum effort to complete the task of the operation instruction.
(4) Gesture interaction: Vehicle gesture interaction refers to the system that controls the car through the transformation and combination of gestures, which enables the owner to realize the given instructions faster, such as switching online radio stations, switching songs, browsing pages, volume mediation, answering and dropping phone calls, etc. Some of these gestures have evolved from touch interaction, while others are based on how people operate.
In the on-board system, the advantage of gesture interaction is that it can be carried out by “not so accurate” operation. In the process of driving, the principle of HMI is to make the driver’s attention focus on the unpredictable road conditions and reduce the attention on the command operation. And quality is often a combination of things exist, the disadvantage of gesture interaction is such interaction is relatively scarce, so you need the driver to such operations have a more profound memory, but to not familiar with operation of drivers, driving back even when interaction gestures, easily lead to focus too much on the interaction.

3) Exchange information

(1) The content shows that: in the process of driving, the driver should put most of his energy on driving the car, and the proportion of time and energy used in HMI operation is very low. Therefore, HMI is required to have the function of fast information transmission. In order to achieve fast information transmission, we can start from the following aspects:
HMI layout design, through the layout of important information placed in the most easy to see the driver area;
The information level of HMI shows that this is relatively basic. It can achieve the effect of fast transmission by strengthening the important information level and weakening the secondary information level.
The integrity of HMI information should be ensured to present more perfect information in the limited interface, minimize unnecessary thinking caused by users’ operations, avoid unnecessary page jumps, and enable users to master the information they want to know within 1-2 seconds.
The unity of HMI information, in the layout of important information, in the system to achieve unity, cultivate the user’s inertial thinking, a thing repeated to do more naturally skilled.
(2) operating hotspots: HMI design should fully consider the drivers use feeling, (which involves a number of human body engineering knowledge) driver in the process of driving, body under certain constraints, so want to finger touches the screen far distance yourself is takes extra attention, but also take into account the driver’s vision.
Therefore, the high-frequency operation area and key information area should be placed in the hot operation area as far as possible, and the distance between the operation area and the driver should be shortened as far as possible. At the same time, the information content presented will be clearer. Otherwise, other information can be placed on the right side of the screen.
(3) Interactive copy: HMI interactive copy must be concise and easy to understand, so that the driver can complete the operation in the shortest time with the least effort, without ambiguity, and understand the feedback brought by the interaction ~

Clear meaning:
The meaning of interactive copy must be clear and clear, refuse to be vague.
For example: when a user uploads a profile picture, if the upload fails.
Bitter chestnut: Profile picture upload failed
Sweet Chestnut: Failed to upload profile picture, upload picture resolution is too low
Sweet chestnut not only feedback to the user results, but also tell the user the cause of the unsatisfactory results, let the user further know how to do to get positive feedback ~
The hierarchy is clear:
Here is the most basic concept of comparison, which can strengthen the main copy and weaken the secondary copy to help users distinguish the importance of information, read the most wanted information content in the shortest time, and help users understand, there is no more to repeat here ~

Copy simplification:
When people use an app and see the feedback popover, will they only see the larger and bolder text, and ignore the auxiliary text below? Want to hit the “OK” button quickly?
Users are children “grumpy”, so in the design document, we should to refining of copywriting, reduce the cost of the user’s reading as much as possible, after all, has a high percentage of users don’t want to read a word ~ directly tells the information necessary to get rid of the statement is of guiding significance for action, focusing, Just tell the user where they are and what to do next.
The copywriting is consistent:
The consistency of interactive copywriting should be ensured. In the preparation of similar copywriting, the attributes of words and the sequence of word combinations should be clarified.
Shorten the path:
If it does require a long document, provide a way for the user to shorten the path so they can read the message and say, “This is all I need to do.”
Bitter chestnut: “I know”, “Sure”
Sweet chestnuts: “Go”, “Go now”, “Go set”
At the interactive level, it can clearly know what users do and reduce the operation cost of users.

IoT and interactive functions of HMI touch screen

4)Interactive feedback

Interactive feedback in HMI is usually expressed in three forms: visual, touch and voice. The feedback information should directly and clearly tell the driver what he or she most wants to know.
(1) Visual feedback: Take the reversing image as an example. When the vehicle is in reverse operation, the large screen of central control will automatically plan the reversing track for the driver. If there is going to be a collision, a red warning message will appear.

(2) touch feedback: touch feedback is different from the hardware button operation feedback is clear, has certain security hidden danger, therefore, vibration feedback and dynamic feedback becomes a clear feedback mechanism based on operators, used to move the scene is more, HMI restricted by usage scenario application range is not wide, so should from the visual and tactile level.
(3) voice feedback: the above mentioned the importance of voice interaction function in vehicle system, using voice dialogue way feedback to the operation of the user, the user to use low cost to obtain feedback channel, through intelligent dialogue mechanism to comprehensive description the problem, the beard also specially out an article on the HMI voice interaction with everybody share

Four, the landing of HMI

After understanding the basic concepts, design and interaction of HMI, you must be curious about how HMI is implemented. Where is the HMI in the whole project link? Let me show you what it is!

1) Vehicle development process

Before introducing the development process of HMI for you, I will briefly introduce the development process of the vehicle for you, so that we can clearly know which link HMI is in the development process of the vehicle.

The whole can be divided into five links:
(1) Product strategy: After market research and user demand analysis, auto manufacturers find out the relatively blank areas of the market, formulate the corresponding market strategy, and formulate the strategic target of the whole product.
(2) Conceptual design: Conceptual design is divided into two stages. After preliminary market research and user demand analysis, the data are summarized and converted into product design objectives to obtain the initial concept; After the full communication between product function design and development, the project objectives are formally confirmed, and the following specific design process can be carried out.
(3) Design and development: refine and improve product design, HMI design is one of them.
(4) Engineering vehicle: including further optimization of system and parts, and production of sample vehicle.
(5) Production and manufacturing: after confirming the sample car, determine the mass production trial production, conduct production play, after comprehensive verification, the vehicle can start mass production ~

2)HMI development process

HMI development is only a small part of the overall development perspective, but as manufacturers increasingly focus on user experience, HMI designers will be involved in more links in the future. HMI designers are also subdivided into many positions: user research, interaction design, visual design, dynamic design, sound design, 3D design, and so on. Designers also need to interact with students from marketing, planning, technology, brand and other departments.
So what is the specific development process of HMI?

(1) the requirement review: through market research and user research to explore the specific needs and requirements of sources can be divided into three categories: corporate strategy, market, technology development, after a summary of demand, need analysis to evaluate the demand for high value, such as: portrait application scenarios, specific function, user demand, the core content, etc.
The core three elements of requirements review: value, function and landing.
Value: What is the starting point for requirement initiation? What value does it bring? Quantifying the value;
Functionality: What functionality does the product need to support in order to achieve value? For example: good-looking, easy to use, novel, high-tech, high quality, etc.;
Landing: Analyze how to landing and landing cost for each function point.
In a word, requirements review is the foundation of a grand project, for the project to carry out comprehensive and detailed planning, to ensure the smooth completion of the project.

(2) Creative Design: Design phase is divided into early and late two stages, fully aware of the product at the early stage of the design demand, combined with market research and the contents of the user requirements and data, the core content of extracting requirements into the design goal, in the early design stage, output before docking with the product, develop students, until the establishment of formal project target, the late into the design phase, Start designing specific processes and other details.
(3) Landing evaluation: After the completion of the design phase, it is necessary to enter the verification procedure, pass the bench simulation test, or provide specific evaluation vehicles and training vehicles, and further analysis and quality assurance road test to carry out the experiential verification. After running the verification procedure, it entered the traditional link of system development, hardware development, software development and vehicle testing ~
(4) Development and testing: after finishing the previous procedures, the final stage of the design is to follow up the development and verification link. After confirming the sample car, we will determine the mass production and trial production. After the comprehensive verification, the vehicle can be put into mass production.

Scroll to Top