Exoskeleton structure that provides force assistance to the user

An exoskeleton subassembly is provided. The exoskeleton subassembly includes first and second exoskeleton parts, and a connecting assembly that connects the first and second exoskeleton parts. The connecting assembly includes a guide, a pin, and a limiting device. The guide is fixedly mounted on one part, and a pin fixedly mounted on the other part and slidably mounted inside the guide. The limiting device allows rotation of the pin with respect to the guide when the pin is in a first position, and to oppose the rotation when the pin is in a second position. The limiting device includes an elastic element engaged with the first part when the pin is in the second position. The elastic element exerts on the first part an elastic return force opposing relative rotation between the first and second parts both in two opposite directions of rotation.