![What is this black Spinning thing on top of big black van? Ot speeds up and slows down, relative to the vehicle speed. I though maybe self driving radar, but maybe just What is this black Spinning thing on top of big black van? Ot speeds up and slows down, relative to the vehicle speed. I though maybe self driving radar, but maybe just](https://i.redd.it/wfc65xdyhct11.jpg)
What is this black Spinning thing on top of big black van? Ot speeds up and slows down, relative to the vehicle speed. I though maybe self driving radar, but maybe just
![What is this black round thing on the roof of this transit company van? It was spinning fast. : r/whatisthisthing What is this black round thing on the roof of this transit company van? It was spinning fast. : r/whatisthisthing](https://external-preview.redd.it/srFjPkvF_1Ji90VF6xh2uEWiQfEW3sTHzsXHu4i0Kc0.jpg?auto=webp&s=bbc7ce94a0920ef3ec72d02f2f0a3219d97ddf21)
What is this black round thing on the roof of this transit company van? It was spinning fast. : r/whatisthisthing
![What is this round spinning thing on the back of a utility truck? It only spun when the van was moving. : r/whatisthisthing What is this round spinning thing on the back of a utility truck? It only spun when the van was moving. : r/whatisthisthing](https://i.redd.it/px9ajr2h56b11.jpg)