This is the Cam Pipe Clamp fixture from the Supplementary Material of Koyama et al.'s paper "AutoConnect: Computational Design of 3D-Printable Connectors"
https://koyama.xyz/project/AutoConnect/autoconnect.pdf
https://koyama.xyz/project/AutoConnect/supplemental.pdf
The author marked this model as their own original creation. Imported from Thingiverse.