Welcome to Lexi!

Here you’ll find comprehensive information for developing for the Lexi Platform and our API endpoints. We’ve tried to make this documentation user-friendly and example-filled, but if you have any questions, please contact us. If you’re planning to use our API in production, take a look at our privacy policy.

To get you started, here is a quick overview of the Lexi Platform. The Lexi platform has a number of different subsystems.

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1. App
(iOS and Android)

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2. Hub

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3. Lexi bulbs and
devices

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4. Cloud App

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5. Marketplace

Here is an Architecture Diagram that demonstrates the relationship of these subsystems.

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Lexi Platform Overview

The Lexi Mobile App is be used for command & configuration of the Lexi system. A user creates a Lexi account either using a Mobile app or the Cloud app. Once the account has been created, a user can sign into the Lexi Platform.

Initial Hub Configuration

When you first purchase the Lexi products, Hub needs to be configured (except in No Hub mode-see below). User powers on the Hub and the Hub understands it does not have an IP address and automatically starts “Access Point” mode. The Mobile Apps can then connect to the Lexi Hub Access Point and ask it to start a secondary Bluetooth or BLE interface. The App then connects to the Bluetooth /BLE interface as well and uses it to send the WiFi configuration. The Hub once connected to the WiFi system configured by the user sends the IP of the Hub to the Mobile App. This way the App can now communicate with the Hub using the IP address.

Device Configuration

Once the Hub has been configured, all the Lexi Devices can then be configured. The Lexi system supports a variety of Lights (Standard Bulbs, Non Standard Lights (Down Lights, Strip Lights, String Lights) and our ART Lights) as well as Sensors including the Micro MultiSensor. All Lexi Devices have BLe Mesh chipsets and use that as their primary communication protocol. In addition, the ART Lights also have a 900MHz radio chipset as well. BLe Mesh pairing is initiated by the Mobile App. The Mobile App scans for available Lexi Devices and shows user a list of BLE Mesh Devices. The user can then select the device to pair. Once the pairing is complete, the Mobile App then sends the Device information to the Hub that then can control the lights. Once the Hub and Devices have been configured, the user can start using the Lexi system.

Light Functionality

Smart Lights themselves have limited functionality-1. turn on/off, 2. set brightness, 3. set Color Temperature (for White) or 4. Color (for RGB). The rest of the functionality is in the software. Lexi software supports the ability to set these four functions on an individual light basis, as well as in user defined groups or universally. Users can also create schedules, rules, scenes and Light Shows which dynamically adjust these for settings.

Multiple System Control

Since the user can own more than one Lexi Lighting System, the Mobile App supports multiple Hubs. For example: if the user has one Lexi System at home and another one in the office, All he/she has to do is Select the Switch Hub option from the menu and select the appropriate Hub. As soon as user does this, the Mobile App loads the device information and configuration for that particular Hub and user can then use that particular Lexi Light System.

Multiple User Control

Lexi also supports multiple users controlling a single Hub. For example if Husband and Wife both want to be able to use the home Lexi Light System from their individual phones, it is possible and enabled in Lexi. The first user who configured the Hub has click on “Share Hub” option from the Mobile App menu. A unique code is then generated for the Hub. This code can be shared with the user who needs access to this Hub. The second user can then initiate the process of Add Hub and select the claim Hub option. User will be asked to enter the access code, after which that user will be added as one of the users of the Hub and can control the Hub in exactly the same way as the first user.

Deleting Devices

Users also have the ability to delete a device or delete the Hub. (Delete Hub will delete all devices along with the entire setup).

Cloud App

Lexi has also developed a Desktop App running in the cloud. Users use the same username and password from the Mobile App to sign into the Cloud App as well. The Desktop App provides users the ability to manage their devices, view the reporting of their lights & sensors, upload, sell & manage their light art, purchase light art & manage those purchases and share their light art and manage those shared with them. For every action the User performs in the App, the Hub captures data and sends it to the Cloud App.

Device Grouping

Lexi allows devices to be grouped. Once grouped, multiple devices can be controlled together. Functionality allowed for group action: Group On/ Group Off, Change group color, Change group brightness and Change group color temperature. Group also is needed in advance concepts like Rules where are rule can be applied for a group of devices.

Favorites

User can also set scenes or patterns as favorites and run them with a single switch on one or more devices or groups.

Schedules & Rules

Users can create own their schedules that can then be used in Rule creation. Lexi supports IFTTT (IF This Then That). Rules in Lexi have A 3 parts: A trigger, activity and output devices. A trigger can be a schedule or a sensor input or a telephone event ( a voice call or a message). A Rule is initiated upon a trigger event. The activity is the action that will be performed in case of the rule trigger. An activity can be turning on/off, changing brightness, changing color temperature or color or initiating a scene or a light show. Output devices can be one or more devices or a group. A rule can also be a complex set of conditions. For example, user can create a rule to turn on/off lights based on input from the light sensor. User can also create rules based on schedules (evening/day time). A rule has to be activated after creation. All entities which are part of an active rule cannot be deleted.

Light Art

Scenes

A scene is one or more colors that operate across a group of lights. Scenes with multiple colors are defined by selecting the colors in order of their appearance, transition times between colors and length of time of each color. User can also define the number of cycles for the scene and also the end color. Lexi also provides a number of predefined scenes. User can also modify pre-defined scenes and save them. User can also import scene from external file. User can preview a scene, play/stop a scene. A scene can be played either on one or more devices or a group.

Patterns

Patterns are patterns of light that move across a single device which incorporates more than one light source such that different light sources on the device show different colors at the same time. Lexi provides pre-defined patterns as well as the ability to create your own patterns within the Mobile App. Users can also modify existing pre-defined patterns and save them as original creations. There are different kinds of patterns: User can draw the pattern, They can enter text to create a pattern or upload an image and have that converted to a pattern. User can then select the duration to run the pattern. For text patterns, user can select how the text appears on the output device and how it goes away. Text patterns can only be run on LED Matrices.

Light Shows

Light Shows are patterns that run across multiple devices at the same time. Lexi supports the ability to run multiple light shows simultaneously across different groups of lights. Lexi provides pre-defined light shows. Users can also create their own light shows within the Lexi Mobile App as well as through the Desktop App.

Creating Light Art

Lexi provides several ways to create Light Art.

Scene Creation

To create scenes, users can select colors from a color wheel in priority order, designate the total duration of the scene, the transition style and the number of cycles to run the scene. Another method we call “Color Path” which is to draw a path through a color wheel to designate the sequence of colors desired. Users then select the duration and number of cycles.

Light Shows

Light shows are patterns run across multiple lights simultaneously. Light Shows are three-dimensional. In order to properly run a Light Show then we must know the spatial position of each light relative to one another in x,y,z space. How we determine the spatial position of each light depends upon whether the lights are indoors or outdoors. In the case of indoor lights, we use RSSI-Received Signal Strength Indicator, to determine the position of each light from a Reference Point. The Reference Point in our case is user’s mobile phone held in a constant position while it scans the signals of all the lights. In the case of outdoor lights, our lights include a GPS chip, so we collect the GPS coordinates of each light. Then, in both indoor & outdoor cases, we store the coordinates of the lights in a database. From the database we then create a cube which is sufficiently sized to encapsulate all the users lights. By defining a cube, regardless of dimensions of the cube, we have normalized all possible configurations of a user’s lights. Our light show software creates & runs 3D patterns across 3D cube space. With a normalized cube view of all users light configurations, regardless of actual distances of individual user’s cubes, we can then run any light show across any user’s light configuration by simply affixing the lights into the 3D cube space of the light show software.

Gesture Creation of Light Art

Users can utilize the accelerometer of their mobile devices to create Light Art. To create Scenes using gestures, users either shake, tap or draw paths on the screens on their mobile phone. These movements are then used to dictate the frequency of changes in the lights brightness, color temperature or color transitions. To create Light Shows using gestures, Users trace a path in 3D space with their phone and then assign that to one or more colors or a color path (as defined earlier). Lexi also works with motion capture devices to translate movement of multiple motion points, such as 5 fingers in a motion capture glove, to create/direct a light show in the same manner as using a phone to translate the motion of the fingers into light patterns across the normalized cube of a users lights in 3D space.

Sharing

Users can share Light Art they have created by generating a link within the Mobile App and then distributing that link via email, text, messaging within the Mobile App, to other Lexi users. Once the receiving user clicks on the received link, the Light Art creative file is transferred to his account and he can begin using it on his lights.

Music Control

The Lexi Mobile App enables music control of Scenes and Light Shows that are modulated by sound input. In this user can select a song from his/her phone library or they can select the microphone option as a music input device.

Over the Air Updates

When new features are available, the Mobile App will receive notification and user can upgrade the Hub and all devices with new software.

Security

There are multiple places where authentication takes place in the Lexi Platform. To sign in to the app user needs a user name and password. Once the User adds a Hub, the User data is stored on the Hub. Every command sent by the Mobile App is authenticated against the User and command is rejected if authentication fails. Similarly, this is how Hub to Device authentication takes place.

Third Party Lights

Lexi also work with third party lights like Philips Hue. In order to add the Philips hue lights to the Lexi Mobile App, the User clicks on the Add device option and then selects Add Hue Lights. The Mobile App then scans the local network for all Hue lights and shows user the list of available lights. Once the user selects the light to be added to the Lexi system, the Mobile App then adds these light information to the hub and from that point onwards the entire Philips hue functionality is then available thru the Lexi Mobile App. In other words, The Philips hue can now work as a Lexi Light.