Robotic Balance Training to Improve Postural Control and Balance Post-Traumatic Brain Injury

Participants with TBI: Inclusion Criteria: * Be between the ages of 18 and 65. * Have been diagnosed with a TBI by a physician and be at least 6 months post injury and not more than 5 years post injury. * Have been medically stable for 3 months prior to the most recent TBI. * Not plan to make any drastic changes to medications (as determined by study staff) for at least 4 weeks. * Be able to stand unsupported for 5 minutes. * Be willing and able to give informed consent. * Be able and willing to comply with study procedures, verbal instructions, and follow-up requirements. Exclusion Criteria: * Weight above 300 lbs. * Have severe cardiac disease such as heart attack or moderate or severe congestive heart failure. * Have a pre-existing condition resulting in significant disruption in alignment or function of the lower limb during standing. * Have additional medical conditions that affect the bones, muscles or nerves that would interfere with the balance. * Have any previously diagnosed history of balance problems prior to TBI. * Have fluctuating blood pressure. * Be on any medication that may affect balance, strength, or muscle coordination (e.g. Botox). * Be currently enrolled in another research study that is likely to affect participation in this research study. * Have seizure disorder. Participants without a disability: Inclusion Criteria: * Be between the ages of 18 and 65. * Not plan to make any drastic changes to medications for at least 4 weeks. * Not have an orthopedic, cognitive or neuromuscular disease. * Be able to stand unsupported for 5 minutes. * Be willing and able to give informed consent. * Be able and willing to comply with study procedures, including follow-up requirements. Exclusion Criteria: * Weight above 300 lbs. * Have a history of injury to my lower limbs in the past 90 days. * Have severe cardiac disease such as heart attack or moderate or severe congestive heart failure. * Have a pre-existing condition resulting in significant disruption in alignment or function of the lower limb during standing. * Have any additional medical conditions that affect my bones, muscles, or nerves that would interfere with the movement or the ability to feel touch or pain. * Have difficulty following or responding to commands that would limit the study participation. * Be currently enrolled in another research study that is likely to affect participation in this research study.