Question about iRobot Roomba j7+

Hello Greg_ory
Thank you for your question. It is generally quite difficult for vacuum robots to exceed a height of 3-5 cm. We are talking about a Roomba being able to cross thresholds of max. 1.6cm to 2cm. From some users, who did not want to do without their Roomba, we have already heard and seen how ramps were largely made out of plastic or even constructed. This way the Roomba is able to drive over them effortlessly.
If you are unsure, iRobot always offers the possibility to borrow a test device for a fortnight free of charge - unfortunately, we cannot provide you with the ramps.
We hope we have been able to help you with this and are happy to answer any further questions or clarifications you may have.
Best regards,
Your iRobot Team

I think everything higher than 1-1.5cm is a blocker for roomba. you can try to build some kind of ramp...