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Introduction and testing of an alternative control approach for a robotic prosthetic arm.

Griggs L, Fahimi F - Open Biomed Eng J (2014)

Bottom Line: An experimental 4DOF robotic arm was used as the platform for testing the proposed control approach.The two control methodologies, joint control and Cartesian control, were tested on five able-bodied human subjects.Improvement of one control methodology over the other was measured by the time it took for the subjects to complete a simple motor task.

View Article: PubMed Central - PubMed

Affiliation: Mechanical & Aerospace Engineering University of Alabama in Huntsville, Huntsville, 35899 Alabama, USA.

ABSTRACT
Commercially available robotic prosthetic arms currently use independent joint control. An alternative controller involving only control of the hand in a Cartesian frame rather than controlling each joint independently is proposed and tested. An experimental 4DOF robotic arm was used as the platform for testing the proposed control approach. As opposed to joint control, Cartesian control requires the solution to the inverse kinematics problem. The inverse kinematics solution was developed for the robotic arm using the extended Jacobian method. The two control methodologies, joint control and Cartesian control, were tested on five able-bodied human subjects. Improvement of one control methodology over the other was measured by the time it took for the subjects to complete a simple motor task. The timed trial results indicated that Cartesian control was both more intuitive and more effective than joint control. So, the results suggest that much improvement can be achieved by using the proposed Cartesian control methodology.

No MeSH data available.


Related in: MedlinePlus

Average percentage improvement in trial times. (Positivepercentage represents a decrease in trial time compared to Jointcontrol).
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Figure 12: Average percentage improvement in trial times. (Positivepercentage represents a decrease in trial time compared to Jointcontrol).

Mentions: Fig. (12) includes the percentage decrease in trial time averaged over the five subjects. A positive percentage represents an improvement over the average joint control time, and the error bars represent ± one standard deviation. The w -value () of the data in Fig. (12) suggests that the result is significant at . In general, both Cartesian controllers were more effective than the joint controller; only two version 1 Cartesian controller trials resulted in average percentage increases in time, and the percentage increases were less than 10%. When subject 5 was removed from the average calculations, shown in Fig. (13), these two percentage increases in time became small percentage improvements. Fig. (13) clearly shows the advantage of version 2 of the Cartesian controller with average percentage improvements over all trials and average percentage improvements of up to 100%. The w -value (=0) of the data in Fig. (13) suggests that the result is significant at p ≤ 0.05.


Introduction and testing of an alternative control approach for a robotic prosthetic arm.

Griggs L, Fahimi F - Open Biomed Eng J (2014)

Average percentage improvement in trial times. (Positivepercentage represents a decrease in trial time compared to Jointcontrol).
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4231378&req=5

Figure 12: Average percentage improvement in trial times. (Positivepercentage represents a decrease in trial time compared to Jointcontrol).
Mentions: Fig. (12) includes the percentage decrease in trial time averaged over the five subjects. A positive percentage represents an improvement over the average joint control time, and the error bars represent ± one standard deviation. The w -value () of the data in Fig. (12) suggests that the result is significant at . In general, both Cartesian controllers were more effective than the joint controller; only two version 1 Cartesian controller trials resulted in average percentage increases in time, and the percentage increases were less than 10%. When subject 5 was removed from the average calculations, shown in Fig. (13), these two percentage increases in time became small percentage improvements. Fig. (13) clearly shows the advantage of version 2 of the Cartesian controller with average percentage improvements over all trials and average percentage improvements of up to 100%. The w -value (=0) of the data in Fig. (13) suggests that the result is significant at p ≤ 0.05.

Bottom Line: An experimental 4DOF robotic arm was used as the platform for testing the proposed control approach.The two control methodologies, joint control and Cartesian control, were tested on five able-bodied human subjects.Improvement of one control methodology over the other was measured by the time it took for the subjects to complete a simple motor task.

View Article: PubMed Central - PubMed

Affiliation: Mechanical & Aerospace Engineering University of Alabama in Huntsville, Huntsville, 35899 Alabama, USA.

ABSTRACT
Commercially available robotic prosthetic arms currently use independent joint control. An alternative controller involving only control of the hand in a Cartesian frame rather than controlling each joint independently is proposed and tested. An experimental 4DOF robotic arm was used as the platform for testing the proposed control approach. As opposed to joint control, Cartesian control requires the solution to the inverse kinematics problem. The inverse kinematics solution was developed for the robotic arm using the extended Jacobian method. The two control methodologies, joint control and Cartesian control, were tested on five able-bodied human subjects. Improvement of one control methodology over the other was measured by the time it took for the subjects to complete a simple motor task. The timed trial results indicated that Cartesian control was both more intuitive and more effective than joint control. So, the results suggest that much improvement can be achieved by using the proposed Cartesian control methodology.

No MeSH data available.


Related in: MedlinePlus