Skip to main content

Table 2 Summary of possible performance metrics that could be used in assessment tasks and fun therapy tool [41]

From: Potential of a suite of robot/computer-assisted motivating systems for personalized, home-based, stroke rehabilitation

Assessment Category Metric Name Definition Remark
Range of Motion (ROM) ROM Area Ratio The ratio of the area size of user capability space to the input device work space. Reflects the user's Movement Range in the range [0, 1]; ideally this value should be close to 1.
Discrete Tracking Reaction Time The time from the jump of the target to the first significant movement by subject. Reflects the human machine system response Capability (Reaction quickness).
  Movement Time The time between the end of the reaction time to the time after the human subject stayed within the target stably. Reflects the Movement Quickness.
  Movement Speed Movement speed is the average speed within the movement time window. Reflects the Movement Quickness in the movement time window.
  Error The average distance from the target position to the subject position. Reflects overall performance Accuracy.
  Deviation The average distance from the subject position to straight target path line. Reflects Movement Curvature. This metric is for Joystick only.
  Peak Speed Number The number of peaks in the speed profile within the movement time window. Fewer PN represent fewer periods of acceleration and deceleration, making a more Smoothness movement.
  Dwelling Percentage Time in Target The percentage of time subject staying in the target during the dwell window period. The metric is in the range [0, 1]; ideally this value should be close to 1.The higher value indicates a better Stability performance.
Continuous Tracking Percentage Time on Target The percentage time the human subject staying within the target Reflects overall performance Accuracy and Stability.
  Root Mean Square Error The squared root of the mean-squared distance from subject position to the target position. Reflects movement Accuracy.
  Average Deviation The average deviation distance from the subject position to straight target path line. Reflects Movement Curvature. This metric is for Joystick only.
System Identification Perturbation Range The movement range of the human subject in the perturbation direction. Depends on the instruction to human subject. In case "holding" instruction, the bigger value
  Perturbation Standard Deviation The standard deviation value of the human subject position in the perturbation direction. indicates weak Strength; in case "relax" instruction, the bigger value indicates less Muscle Stiffness.
Fun Therapy ROM Intensity Image The human subject ROM movement image with the high intensity indicates intensive human movement area. Reflects Movement Range and Intensity without overwhelming with movement data when task context is unknown.
  Motivation Score Used as a multidimensional assessment tool to evaluate subjects' subjective experience related to a target activity in laboratory experiments Reflects Motivation