We have door thresholds between 2.5 - 4.0 cm. Has anyone found a similar situation and a practical, cheap solution so that Robbi can climb these thresholds?
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"Ramps" work well. I have a rule with a base that is just over 3 cm thick. Once a thin booklet slipped out, so that it formed a ramp from the floor to the rule. The robot then climbed the shelf ;-)
I would have thought of hands, which everyone normally has at home. Otherwise, you would almost have to build a ramp/ledge or possibly lay a carpet over the threshold. 4 cm is almost a wall for these hoover robots.