A canteen with a braille menu, but you need a buzzer to pick up your order¶

This example demonstrates the Interactable interface. You can use it to describe each step required to engage in the key purpose of a place, and to describe optional ways of engagement.

The descriptions can contain barriers, means of interaction, and required abilities and senses.

For a blind person who can read braille (like 90% of employed blind adults in the US), it might be interesting to know that the menu of this canteen features braille print, but they might ask for help to pick up an order.

Describing the ordering process¶

To describe interactions, first add the interactions property to properties.accessibility:

{
  "accessibility": {
    "interactions": {
      …
    },
  }
}

For each interaction, add a property to interactions:

{
  "accessibility": {
    "interactions": {
      "order": { … },
      "pickUpOrder": { … },
    },
  }
}

In this case, we describe ordering food (order) and picking up your order (pickUpOrder). You can find all allowed property names in the GenericInteraction documentation, and that they vary between types – a vending machine's interaction set differs from a place's interaction set. A11yJSON does not allow arbitrary strings here for consistency reasons – this might enable you to gather accessibility statistics later, and results in a standardized set of common use cases. If you use case is missing but very common, feel free to create a pull request – or simply use main, which is the default interaction that happens at a location.

Interaction = action, feedback, and perception¶

In our model, an interaction consists of something you need to do (described in the action property and ActionMode type), feedback to what you do (described in action.feedback and the PerceptionMode type), and something you perceive (described in perception).

Necessities for an interaction to happen¶

For an interaction to happen, you need an InteractionMode, and specific, varying abilities. Some of these abilities are required to engage in the key purpose of a place, some can be optional, and some happen always, no matter if needed or not. The Necessity type has a list of these necessities we ascribe to an interaction mode or ability.

Ordering food¶

To order something, guests can use English language (en) or American Sign Language (ase). The staff responds in the same languages, and hands over a buzzer. In our example canteen, using a buzzer is required. It has no other means of announcing that your order is ready to pick up.

{
  "order": {
    "action": {
      "languages": ["en", "ase"],
      "signLanguage": "optional",
      "feedback": {
        "languages": ["en", "sgn-ase"],
        "signLanguage": "optional",
        "buzzer": "required",
      },
    },
    "perception": {
      "braille": "optional",
      "signLanguage": "optional",
    },
  }
}

Pick-up announcements¶

What abilities do you need to pick up food in this canteen? First, visitors need to find out that their orders are ready somehow. Our example canteen uses buzzers. Like most buzzer devices in gastronomy, our buzzers have multi-sensory output. The pickup process provides several sensory options (visual, tactile, sound) and always-happening outputs of various kinds (beep, flash, tactile, vibration).

{
  "perception": {
    "visual": "optional",
    "sound": "optional",
    "tactile": "optional",
    "beep": "always",
    "flash": "always",
    "vibration": "always",
  }
}

Picking up food¶

An order is ready for pick-up. In a self-service canteen, the staff doesn't help you with carrying, which might be a barrier if you have a mobility impairment. So to move your order to your table, you need to be able to carry a specific weight:

{
  "pickUpOrder": {
    "description": {
      "en": "You need carry the tray to your table yourself or ask for help.",
    },
    "action": {
      "carryWeight": "required",
      "weight": {
        "min": 0.5,
        "max": 2,
        "unit": "kg",
      },
    },
  }
}

Finally, we add helpful textual description attributes to the process steps. Here is the full example (in TypeScript):

import { PlaceInfo } from '../PlaceInfo.js';

const canteenWithBrailleMenuAndBuzzer: PlaceInfo = {
  geometry: {
    type: 'Point',
    coordinates: [-73.985664, 40.748817],
  },
  properties: {
    name: {
      en: 'Canteen at the End of the Universe',
    },
    category: 'restaurant',
    accessibility: {
      interactions: {
        order: {
          description: {
            en: 'You can order in sign language, and the menu is in Braille. You get a buzzer after ordering.',
          },
          action: {
            languages: ['en', 'sgn-ase'],
            signLanguage: 'optional',
            feedback: {
              languages: ['en', 'sgn-ase'],
              signLanguage: 'optional',
              buzzer: 'required',
            },
          },
          perception: {
            braille: 'optional',
            signLanguage: 'optional',
          },
        },
        orderAnnouncement: {
          description: {
            en: 'When the buzzer announces your order, you have to pick it up at a separate counter. The staff there speaks sign language.',
          },
          perception: {
            visual: 'optional',
            sound: 'optional',
            tactile: 'optional',
            beep: 'always',
            flash: 'always',
            vibration: 'always',
          },
        },
        pickUpOrder: {
          description: {
            en: 'You need carry the tray to your table yourself.',
          },
          action: {
            carryWeight: 'required',
            weight: {
              min: 0.5,
              max: 2,
              unit: 'kg',
            },
          },
        },
      },
    },
  },
};

export default canteenWithBrailleMenuAndBuzzer;