Stability control of grasping objects with different locations of center of mass and rotational inertia

Gregory P. Slota, Moon Suk Suh, Mark L. Latash, Vladimir M. Zatsiorsky

Research output: Contribution to journalArticle

5 Scopus citations


The objective of this study was to observe how the digits of the hand adjust to varying location of the center of mass (CoM) above or below the grasp and rotational inertia (RI) of a handheld object. Such manipulations do not immediately affect the equilibrium equations while stability control is affected. Participants were instructed to hold a handle, instrumented with 5 force-torque transducers and a 3-D rotational tilt sensor, while either the location of the CoM or the RI values were adjusted. On the whole, people use 2 mechanisms to adjust to the changed stability requirements; they increase the grip force and redistribute the total moment between the normal and tangential forces offsetting internal torques. The increase in grip force, an internal force, and offsetting internal torques allows for increases in joint and hand rotational apparent stiffness while not creating external forces-torques that would unbalance the equations of equilibrium.

Original languageEnglish (US)
Pages (from-to)169-178
Number of pages10
JournalJournal of motor behavior
Issue number3
StatePublished - May 1 2012


All Science Journal Classification (ASJC) codes

  • Biophysics
  • Orthopedics and Sports Medicine
  • Experimental and Cognitive Psychology
  • Cognitive Neuroscience

Cite this