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Design and preliminary evaluation of the FINGER rehabilitation robot: controlling challenge and quantifying finger individuation during musical computer game play.

Taheri H, Rowe JB, Gardner D, Chan V, Gray K, Bower C, Reinkensmeyer DJ, Wolbrecht ET - J Neuroeng Rehabil (2014)

Bottom Line: The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths.We also used FINGER to measure subjects' effort and finger individuation while playing the game.Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke.

View Article: PubMed Central - HTML - PubMed

Affiliation: Mechanical Engineering Department, University of Idaho, Moscow, ID, USA. htaheri@uidaho.edu.

ABSTRACT

Background: This paper describes the design and preliminary testing of FINGER (Finger Individuating Grasp Exercise Robot), a device for assisting in finger rehabilitation after neurologic injury. We developed FINGER to assist stroke patients in moving their fingers individually in a naturalistic curling motion while playing a game similar to Guitar Hero. The goal was to make FINGER capable of assisting with motions where precise timing is important.

Methods: FINGER consists of a pair of stacked single degree-of-freedom 8-bar mechanisms, one for the index and one for the middle finger. Each 8-bar mechanism was designed to control the angle and position of the proximal phalanx and the position of the middle phalanx. Target positions for the mechanism optimization were determined from trajectory data collected from 7 healthy subjects using color-based motion capture. The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths. For initial evaluation, we asked individuals with a stroke (n = 16) and without impairment (n = 4) to play a game similar to Guitar Hero while connected to FINGER.

Results: Precision design, low friction bearings, and separate high speed linear actuators allowed FINGER to individually actuate the fingers with a high bandwidth of control (-3 dB at approximately 8 Hz). During the tests, we were able to modulate the subject's success rate at the game by automatically adjusting the controller gains of FINGER. We also used FINGER to measure subjects' effort and finger individuation while playing the game.

Conclusions: Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke.

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Related in: MedlinePlus

Structural dimensions and configuration angles of the 8-bar mechanism. Reproduced from [23] with permission from IEEE. Goal positions for the proximal and middle phalanges are shown as PG and MG, respectively. The goal angle of the proximal phalanx is μp.
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Figure 3: Structural dimensions and configuration angles of the 8-bar mechanism. Reproduced from [23] with permission from IEEE. Goal positions for the proximal and middle phalanges are shown as PG and MG, respectively. The goal angle of the proximal phalanx is μp.

Mentions: Initial mechanism synthesis attempts explored multiple configurations of Watt type six-bar chains [29], but were ultimately unsuccessful in reproducing the desired output configuration. The final design uses an eight-bar mechanism (Chain 1 from [29]) with revolute joints (see Figure 3). The goal configurations consist of the position (PG) and angle (μP) of the proximal phalanx and the position of the middle phalanx (MG). The mechanism is made up of 10 revolute joints (G, G1, W, W1, W2, H, H2, Y, Y1, and Y2) and 7 links defined by the kinematic chains GW, WHW1, G1W1W2, HPYH2, W2H2Y2, Y1Y2, and YMY1. These links are defined by seven structural angles (α, α2, δ, δ2, γ, γ2, and μ) and 13 structural lengths (d1-11, m, and m2). Figure 3 also shows the seven configuration angles (θ, θ1, ϕ, ϕ1, ϕ2, ψ, and ψ1) that changes as the mechanism moves. The mechanism has 1 DOF so that specifying one of these configuration angles specifies the complete configuration of the mechanism.


Design and preliminary evaluation of the FINGER rehabilitation robot: controlling challenge and quantifying finger individuation during musical computer game play.

Taheri H, Rowe JB, Gardner D, Chan V, Gray K, Bower C, Reinkensmeyer DJ, Wolbrecht ET - J Neuroeng Rehabil (2014)

Structural dimensions and configuration angles of the 8-bar mechanism. Reproduced from [23] with permission from IEEE. Goal positions for the proximal and middle phalanges are shown as PG and MG, respectively. The goal angle of the proximal phalanx is μp.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3928667&req=5

Figure 3: Structural dimensions and configuration angles of the 8-bar mechanism. Reproduced from [23] with permission from IEEE. Goal positions for the proximal and middle phalanges are shown as PG and MG, respectively. The goal angle of the proximal phalanx is μp.
Mentions: Initial mechanism synthesis attempts explored multiple configurations of Watt type six-bar chains [29], but were ultimately unsuccessful in reproducing the desired output configuration. The final design uses an eight-bar mechanism (Chain 1 from [29]) with revolute joints (see Figure 3). The goal configurations consist of the position (PG) and angle (μP) of the proximal phalanx and the position of the middle phalanx (MG). The mechanism is made up of 10 revolute joints (G, G1, W, W1, W2, H, H2, Y, Y1, and Y2) and 7 links defined by the kinematic chains GW, WHW1, G1W1W2, HPYH2, W2H2Y2, Y1Y2, and YMY1. These links are defined by seven structural angles (α, α2, δ, δ2, γ, γ2, and μ) and 13 structural lengths (d1-11, m, and m2). Figure 3 also shows the seven configuration angles (θ, θ1, ϕ, ϕ1, ϕ2, ψ, and ψ1) that changes as the mechanism moves. The mechanism has 1 DOF so that specifying one of these configuration angles specifies the complete configuration of the mechanism.

Bottom Line: The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths.We also used FINGER to measure subjects' effort and finger individuation while playing the game.Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke.

View Article: PubMed Central - HTML - PubMed

Affiliation: Mechanical Engineering Department, University of Idaho, Moscow, ID, USA. htaheri@uidaho.edu.

ABSTRACT

Background: This paper describes the design and preliminary testing of FINGER (Finger Individuating Grasp Exercise Robot), a device for assisting in finger rehabilitation after neurologic injury. We developed FINGER to assist stroke patients in moving their fingers individually in a naturalistic curling motion while playing a game similar to Guitar Hero. The goal was to make FINGER capable of assisting with motions where precise timing is important.

Methods: FINGER consists of a pair of stacked single degree-of-freedom 8-bar mechanisms, one for the index and one for the middle finger. Each 8-bar mechanism was designed to control the angle and position of the proximal phalanx and the position of the middle phalanx. Target positions for the mechanism optimization were determined from trajectory data collected from 7 healthy subjects using color-based motion capture. The resulting robotic device was built to accommodate multiple finger sizes and finger-to-finger widths. For initial evaluation, we asked individuals with a stroke (n = 16) and without impairment (n = 4) to play a game similar to Guitar Hero while connected to FINGER.

Results: Precision design, low friction bearings, and separate high speed linear actuators allowed FINGER to individually actuate the fingers with a high bandwidth of control (-3 dB at approximately 8 Hz). During the tests, we were able to modulate the subject's success rate at the game by automatically adjusting the controller gains of FINGER. We also used FINGER to measure subjects' effort and finger individuation while playing the game.

Conclusions: Test results demonstrate the ability of FINGER to motivate subjects with an engaging game environment that challenges individuated control of the fingers, automatically control assistance levels, and quantify finger individuation after stroke.

Show MeSH
Related in: MedlinePlus