iRobot - Cliff detection sensor helps #Roomba e5 to avoid falling down stairs and other dangerous drop-offs. Learn more about the Wi-Fi connected, Alexa integrated smart robotic vacuum cleaner: https://irobot.in/Introducing-Roomba-e5.aspx | Facebook
A stair robot cleaner - YouTube
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Robot Vacuum for Stairs: What's News?
This flying robot vacuum overcomes the Roomba's biggest weakness: stairs - The Verge
New published patents show Dyson designs for stair-climbing and drawer-opening robots - The Verge