# How does obstacle avoidance compare between Roborock S8 MaxV Ultra and Roomba j9+?

> Expert comparison of navigation and object detection

*Published: 2026-03-20 | Updated: 2026-03-20 | Source: https://shopsavvy.com/answers/how-does-obstacle-avoidance-compare-roborock-s8-maxv-ultra-vs-roomba-j9*

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## Product: Roborock S8 MaxV Ultra
**Brand:** Roborock

Both the [Roborock S8 MaxV Ultra](https://www.amazon.com/dp/B0CSKBXQ68?tag=shopsavvy-20) and [Roomba j9+](https://www.amazon.com/dp/B0C415NHBM?tag=shopsavvy-20) claim to avoid obstacles, and both are pretty good at it. Neither is perfect. If you're expecting a robot that never hits anything, you'll be disappointed by both.

## What's Under the Hood

The [S8 MaxV Ultra](https://www.amazon.com/dp/B0CSKBXQ68?tag=shopsavvy-20) uses 3D sensors plus an RGB camera. It recognizes 73 different object types: shoes, cables, pet waste, toys, and more. The 3D sensing provides depth perception.

The [Roomba j9+](https://www.amazon.com/dp/B0C415NHBM?tag=shopsavvy-20) uses PrecisionVision Navigation. iRobot specifically trained their system on pet waste recognition, which is smart because that's the obstacle nobody wants their vacuum to "discover" the hard way.

## Real-World Performance

### Both Handle These Well
- Pet waste
- Shoes and slippers
- Power cables (usually)
- Pet toys
- Furniture legs

### Where Things Get Messy

**The Roborock sometimes:**
- Eats extension cords despite "seeing" them
- Gets confused by wool and certain fabrics
- Inconsistently recognizes socks

**The Roomba sometimes:**
- Bumps obstacles before recognizing them
- Struggles in the dark
- Gets confused by mirrors and shiny surfaces

## The Pet Waste Question

If this is your main concern, the [Roomba j9+](https://www.amazon.com/dp/B0C415NHBM?tag=shopsavvy-20) has a slight edge. iRobot offers their "P.O.O.P" warranty that specifically covers pet waste incidents. They've trained their AI specifically for this scenario.

The [S8 MaxV Ultra](https://www.amazon.com/dp/B0CSKBXQ68?tag=shopsavvy-20) detects pet waste too, but it's part of a general obstacle avoidance system.

## The Bottom Line

For typical obstacle avoidance in a reasonably tidy home, both work fine. For pet owners specifically worried about accidents, the [Roomba's](https://www.amazon.com/dp/B0C415NHBM?tag=shopsavvy-20) dedicated warranty gives more peace of mind. For general cluttered-home situations, it's essentially a tie.

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*Where this comes from: This answer is based on ShopSavvy's product database, real-time pricing from thousands of retailers, and analysis of user reviews to give you a well-rounded picture.*