Interesting, I know the joints have hydraulic dampers to help with that which also monitor vehicle speed, but I wasn't aware of torque limiting except near the max angle of the joint. The New Flyer artics equipped with ATG joints really whip around corners compared to the Novas. Maybe that's why ATG joints tend to become distorted and resulting in drooping trailer sections, usually more severe on the curbside.
Refer to these two pictures to see what I mean by drooping trailer sections, neither are mine:
Are you guys finding any distortion of the Hubner joints? The HNG 15.3 looks a lot more sturdier built than the ATG joints in New Flyers.
EDIT: Since we're on the topic of bus joints, here is a New Flyer service bulletin containing various images and drawings of the ATG joint used since 2006 (New Flyer used Hubner joints prior to this). https://www.newflyer.com/site-content/uploads/2017/09/tsib-09-03-rev-a.pdf
This is the best picture available for the Hubner joints used on the LFSA, it's the HNG 15.3 model: http://www.hubner-group.com/en/Articulation+Systems-path-1,3144,3150.html
You can also catch a glimpse of the HNG 15.3 in a How It's Made video of a Nova Artic on YouTube around 02:22 in the video.
Both joints yaw occurs roughly in the middle of the joint, however on the Hubner joints the pitch occurs closer to the tractor section, whereas the ATG joints pitch closer to the middle thanks to the wrist joints that extend from the tractor section.