The anode fall region is also a very narrow gap like the cathode fall region.

热阴极辉光放电的阳极区与阴极区一样，是一个很薄的区域。

youdao

Eventually, what we'd like to do is if they see a pipe or a very narrow gap they say, okay my body is too big, it will change to become a snake to go through it.

CNN: Robotics discovers its soft side