Accessible game design

People with limited mobility usually use so-called “on-screen keyboards” instead of a standard keyboard. These are displayed on the computer monitor in the form of a window. When one of the keys is clicked using input devices such as a computer mouse or eye control, the corresponding letter is triggered. They also integrate other useful functions, such as “autoclick”. All the user has to do is hover the mouse pointer over a key and, after a short dwell time, the desired key is triggered automatically. It would be possible to use such on-screen keyboards in text chats in multiplayer games, for example, or for individual key input in games that do not require the player to react quickly.

This type of assistance program can now be found on every modern smartphone. It enables people with limited mobility to operate computers using only their voice instead of having to do so mechanically. Voice recognition can be used to enter text, open programs or position the mouse pointer. One of the best-known and most precise speech recognition software is “Dragon NaturallySpeaking” from Nuance. However, compared to the countless free alternatives, it is quite expensive and not affordable for everyone. Nevertheless, the integration of speech recognition in video games, for example to navigate the game character, is a simple and inexpensive way to make games more accessible for people with motor disabilities.

These devices make it possible to operate computers by means other than a standardized pointing device, such as a mouse. These pointing devices can be eyes, control systems or so-called mouth mice.

Broken down to a simple level, an eye control system, also known as an eye tracker, is a camera that records the movement of the eyes and software that processes and then interprets these camera images. The user's eye movement is thus translated into the movement of the mouse pointer. A mouse click is often triggered by an active blink. Mouth mice, on the other hand, are used with the lips and can be steered in any direction. This movement can be translated into the movement of the mouse pointer, among other things, but is also ideal as a joystick for computer games.

The two systems described can be used in conjunction with the on-screen keyboards mentioned above. This means that a computer can be used completely without any input devices that need to be activated manually.

In contrast to the software approaches described above, which for the most part can only be used to control the user interface of a computer, there are already a wide variety of devices on the market that can be used to facilitate the control of games. People with severe motor impairments often find it very difficult or even impossible to use traditional gaming input devices such as controllers. These people have to rely on alternative hardware that can be individually adapted to their abilities. The following section takes a closer look at some of these devices and how they work.

Programmable input devices were not developed specifically as an aid for physically impaired people, but originate from the market for professional gaming accessories. However, many of these products are also suitable for people with a disability and, compared to expensive aids such as eye control systems, are a relatively inexpensive option for making video games more accessible. Some of these 'gadgets' will now be highlighted.

These special mice have up to 19 side-mounted buttons that can be programmed as required. Players with and without disabilities can therefore customize the gaming mouse to suit their individual needs.

"Scuf controllers” are visually customizable controllers equipped with programmable buttons. For example, the analog sticks can be changed, the resistance of the trigger buttons can be adjusted and the up to four removable paddles on the back can be assigned any function.

External control devices include the aforementioned eye control systems and the mouth mouse. There are also, for example, push buttons, micro switches and foot pedals. Push buttons are ideal for gamers who find it difficult to hit individual small buttons. The micro switches mentioned above are switches that can be triggered by an ultra-light activation pressure of 10g. This type of switch is intended for people who have little strength in their fingers, for example.

All these aids can be placed anywhere, such as behind the shoulders or next to the head. They simply need to be connected to an external control module, which is connected to the computer, for example. However, the control devices only replace one function at a time, such as a double-click or the movement of an analog stick.

The “Xbox Adaptive Controller” was released by Microsoft in 2018. This product is a hub for aids that can be used to make gaming more accessible. These include the aforementioned push buttons, micro switches, foot pedals and mouth mice. These and other assistive devices can be connected via 3.5mm sockets and USB-A ports on the back of the controller and control buttons, joysticks and trigger inputs. An app can also be used to freely assign the buttons to the individual ports. However, the controller can only be used in games from the Xbox One product family and Windows 10.

The so-called “QuadStick” controller was developed by Fred Davison especially for people with paraplegia. It is operated by the user using their mouth. The “QuadStick” consists of a joystick, four push and swallow sensors, a sensor for the lip position and a reversing switch. These sensors are connected to a 32-bit ARM processor that converts the inputs into USB and Bluetooth signals. With the help of suitable adapters, all consoles and Android devices can be operated.

The majority of video games allow the player to configure the game and its controls in the settings, for example by activating subtitles in cutscenes or assigning any button on the controller. In a few isolated titles, a combination of strategies is also used to make the game more accessible for people with motor impairments:

1. reduction: part of the original interaction with a computer game, in the form of mechanical input, is reduced or even completely removed.

2. automation: Parts of the game mechanics are executed automatically. For example, the automatic firing of a weapon in first-person shooters is conceivable.

3. recognition of game situations: Depending on the state of the game, the action performed by a button input changes. For example, if the character is standing in front of a door, a mouse click opens it. If, on the other hand, the character is standing behind an opponent, a mouse click overpowers them. In this case, one keystroke triggers two different actions within the game. Some games that make use of the tactics just described are presented below.

Games from the field of special education in particular have been developed to be accessible from the outset. One example of this is Genesis, a free learning, therapy and game system developed at the Georg Simon Ohm University of Applied Sciences in Nuremberg. In fact, it is an expandable software kit for creating games and exercises for children and young people, mainly with disabilities. The game consists of three main components. The core program “Osim” serves as a kind of graphical user interface. The player uses this to start the individual programs, tests and exercises. The game is operated using input devices that have just a few buttons and can be customized depending on the disability. In addition, the developer tools “OGen” and “Oplus” enable caregivers, teachers and therapists to adapt and expand existing games and create their own games.

The alternative input devices already described restrict the motor-impaired player in terms of limited input options. This section therefore focuses on games that can be played with the least amount of input, so-called “one-switch” games. An example of this type of game is “Gordon's Trigger Finger” from 2008, which is a free-to-play mod for the “Half-Life 2” death game. In this modification, the game character automatically tracks enemies and aims at them. All the player has to do is press a button to precisely time the shots fired from the weapon.

“The Last of Us Part ll” was released in June 2020 for the PlayStation 4. More than 60 setting options make the game more accessible for people with auditory, visual and motor impairments, a first for an accessible mainstream game. Some of the accessibility features were already used for the first time in “Uncharted 4: A Thief's End”. In the following, however, we will focus exclusively on the options for players with motor disabilities.

“The Last of Us Part ll” comes with recommended settings for an accessible gaming experience, which are already preconfigured. Each individual option of the default settings can be further modified and personalized. Some of these options are now described in more detail.

To reduce the number of keystrokes, it is possible to automate the overcoming of ledges, narrow passages and the climbing of the player character. All the player has to do is press a single button.

The controls within the game are fully customizable. This means that each individual control command can be assigned to a different button. It is also possible to deactivate the motion control and touchpad function of the DualShock 4 controller. As many gamers with motor disabilities find it difficult to press individual buttons quickly and repeatedly, it is possible to set buttons to be held down. Furthermore, the position in which the controller is held can be changed and the automatic targeting of the next target and enemies can be activated.

Close combat and firefights require the player to react quickly and use a lot of buttons. Such scenes are largely insurmountable hurdles for those with limited motor skills. To ensure that every player can successfully fight in the game, there are also some options for this. These include, for example, a slow-motion mode when aiming the weapon or the option to remain invisible to opponents when lying on your stomach.

For disabled people, participation in public and cultural life is not fully possible for a variety of reasons. Access to gaming culture is therefore extremely important for such people. As gaming is also possible at home, in an environment that is usually familiar and adapted to their needs, (pop) culture can also be experienced by people with disabilities in this way.

Video games can also be a distraction from everyday life and provide short-term relief and distraction for pain patients, for example. This distraction or attraction emanating from video games is due to the possibility of experiencing adventures in foreign worlds. In addition, things like walking are also made possible for wheelchair users in games. There are no limits. Furthermore, online computer games facilitate social interaction, as environmental barriers do not exist here and the general anonymity means that fears of contact between disabled and non-disabled people can be reduced.

However, the need for accessible video games is hotly debated in the gaming community. Accessibility options are seen by many healthy gamers as an intrusion into the nature of a game, which jeopardizes the enjoyment of the game. Comments on social media platforms such as: “If you can't play the game without assistance, then it's not for you.” reinforce the exclusion of disabled people from the gaming community. 

However, publishers and console manufacturers have started offering more assistance for gamers with disabilities in recent years. The "Xbox Adaptive Controller" by Microsoft is a prime example of this. The fact that these devices are available in regular retail stores leads to non-disabled gamers seeing these devices and thus recognizing and accepting disabled gamers as part of the gaming community.

While the inclusion of disabled users in the gaming community is steadily progressing, the representation of disabled people in the games themselves still leaves much to be desired. Often, only the image of the "depressed" wheelchair user is portrayed. This does not represent the diversity of disabilities and only reinforces existing apprehensions.

It is time to involve people with disabilities in development teams to create universally applicable guidelines for the development of accessible video games. Furthermore, it is crucial to ensure a sensitive and accurate representation of disabled individuals within the games themselves. Campaigns like "#teamdiversity" by the German industry association "game" should be more frequently utilized to promote a balanced, unbiased, and stereotype-free portrayal of all individuals in the gaming industry.

Establishing a comprehensive definition of "disability" proves to be quite challenging in practice. Where is the line drawn between disabled and non-disabled? The definition used in this article is largely recognized by the international community. However, it does not fully capture the diversity of disabilities. This article is no different. In addition to the four types of disabilities described, countless others exist, including multiple disabilities. Therefore, the description of the impacts of the four types of disabilities is fairly superficial, and not all affected individuals face the same challenges when playing games.

As previously mentioned, the focus of this article is on accessible game design for video games with respect to people with motor disabilities. The design for accessibility for other forms of disabilities was not addressed but represents an equally complex challenge and should be considered in the context of comprehensive inclusion of people with disabilities in the gaming community.

The described aids to make video games more accessible to users with motor disabilities are, of course, not a panacea. Many of these technologies, such as eye-tracking systems or mouth-operated mice, are very expensive, and many systems are outdated and only suitable for operating systems like Windows. It is clear that someone severely affected by ALS, who can only move their eyes, will likely never be able to play mainstream games. The aids presented can usually only replace a single input. A single eye movement cannot replicate the functionality of a controller.

Given the limitations described, this article does not provide a definitive or universally valid "recipe" for the accessible design of video games. This is partly due to the limited availability of sources in this field. There is a lack of scientific sources on this topic. Most of the literature used comes from non-profit foundations and organizations such as "The AbleGaming Charity" or "Aktion Mensch." The aids described are often presented in forums by the affected individuals themselves and are typically custom-made or individual solutions. Furthermore, there are hardly any reliable figures or statistics on gamers with physical or mental disabilities. They are usually rough estimates, primarily from English-speaking countries. The limited sources are partly due to the fact that video games, compared to films, are a relatively young medium, and societal skepticism toward gaming is still widespread, particularly in Germany. Additionally, a movement for accessible games is mainly active in the USA.

In conclusion, it can be stated that there are more possibilities for accessible video games than many realize. For example, with the help of controllers that measure brainwaves, it could be possible to make video games accessible to all players with motor impairments. Complex modifications of assistive devices would become a thing of the past. This is conceivable and desirable for the future, but it requires further fundamental research and technological advancement.