Makers of 3D-printed prosthetic hands may come to rely on a printed palm Rice University students developed to help ensure that children get the most out of the devices. The Rice team calling itself Carpal Diem has developed a testing suite to validate how well 3D-printed hands transfer force from the wearer - typically a child born without a fully formed hand - to the prosthetic intended to help pick up and manipulate small objects. The team’s suite consists of a motorized wrist-and-palm assembly that can move up to 60 degrees in either direction, a set of objects (a cylinder, a sphere, and a rectangular prism) with embedded force sensors, and a control program with a graphic user interface. An operator uses the program to bend the wrist and close the printed hand’s fingers and thumb around an object. Sensors in the object send feedback on force strength and distribution to the computer.