Detection of the Bolt Loosening Angle through Semantic Key Point Extraction Detection by Using an Hourglass Network

Figure 11

Recognition accuracy and error under different luminance levels. (a) Loosening angle with a luminance of 70. (b) Loosening angle with a luminance of 50. (c) Loosening angle with a luminance of 30. (d) Loosening angle with a luminance of 10.

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