AWS Greengrass
Developer Guide

AWS Greengrass Example Scenario: Robot Arm

To help you understand how the AWS Greengrass core and its components fit and work together, we have created an end-to-end example scenario. This scenario is detailed and will take some time to complete. If you are looking for a shorter, more high-level introduction, see AWS Greengrass User Guide.

Imagine a robot arm that moves boxes to a conveyor belt. This robot arm is controlled by a switch that will turn it on or off. The robot arm's on/off state can be controlled from the cloud. We have two Lambda functions. One function is for monitoring the robot arm state when it is turned on and off (uptime Lambda). This represents a situation in which you might need to monitor the status of a device, such as how many times its been powered on (a very basic example). This status is sent to the cloud where you are able to see the data on an MQTT topic.

The messageLambda Lambda function accepts generic messages that control the robot arm from the cloud and updates the local thing shadow associated with the robot arm device. The AWS Greengrass core software synchronized the local thing shadow with the thing shadow in the cloud (AWS IoT).