SynGrasp: A MATLAB Toolbox for Underactuated and Compliant Hands. SynGrasp is a MATLAB toolbox for grasp analysis of fully or underactuated robotic hands with compliance. Compliance can be modeled at contact points in the joints or in the actuation system, including transmission. It is possible to use a graphical user interface (GUI) or directly assemble and modify the available functions to exploit all of the toolbox features. Grasps can be described either using the provided grasp planner or by directly defining contact points on the hand with the respective contact normal directions. Several analysis functions have been developed to investigate the main grasp properties: 1) controllable forces and object displacement, 2) manipulability analysis, and 3) grasp stiffness and quality measures. The functions for the graphical representation of the hand and object as well as the main analysis results are provided. The toolbox is freely available at