  Soft grippers have excellent adaptability for a variety of objects and tasks.
Jamming-based variable stiffness materials can further increase soft grippers'
gripping force and capacity. Previous universal grippers enabled by granular
jamming have shown great capability of handling objects with various shapes and
weight. However, they require a large pushing force on the object during
gripping, which is not suitable for very soft or free-hanging objects. In this
paper, we create a novel palm-shape anthropomorphic variable-stiffness gripper
enabled by jamming of 3D printed fabrics. This gripper is conformable and
gentle to objects with different shapes, requires little pushing force, and
increases gripping strength only when necessary. We present the design,
fabrication and performance of this gripper and tested its conformability and
gripping capacity. Our design utilizes soft pneumatic actuators to drive two
wide palms to enclose objects, thanks to the excellent conformability of the
structured fabrics. While the pinch force is low, the palm can significantly
increase stiffness to lift heavy objects with a maximum gripping force of
$17\,$N and grip-to-pinch force ratio of $42$. We also explore different
variable-stiffness materials in the gripper, including sheets for layer
jamming, to compare their performances. We conduct gripping tests on standard
objects and daily items to show the great capacity of our gripper design.
