Figure 1.
Tendon gliding exercise straight (TGE1); tabletop (TGE2); straight fist (TGE3); full fist (TGE4); and hook fist (TGE5).
Figure 1.
Tendon gliding exercise straight (TGE1); tabletop (TGE2); straight fist (TGE3); full fist (TGE4); and hook fist (TGE5).
Figure 2.
Proposed framework for designing and analysing a rehabilitation device for TGE by adapting the process developed for one selected finger to all fingers of the hand. Inputs include patient hand dimensions, target joint angle (TGE1-TGE5), and the parametric soft actuator sub-unit. The framework consists of: (1) obtaining finger geometry; (2) determining joint forces and safety thresholds for patients; (3) identifying tools to characterise actuator response to meet TGE shape and power requirements; (4) determining initial pressure control to achieve TGE and validating for safety through simulations and testing with a dummy finger; and (5) manufacturing and testing the actuator on the patient’s hand, followed by fine-tuning control. The orange text for each functional block denotes what this paper addresses, reflecting a limited scope of the functional blocks needed for the complete pipeline (shown in black).
Figure 2.
Proposed framework for designing and analysing a rehabilitation device for TGE by adapting the process developed for one selected finger to all fingers of the hand. Inputs include patient hand dimensions, target joint angle (TGE1-TGE5), and the parametric soft actuator sub-unit. The framework consists of: (1) obtaining finger geometry; (2) determining joint forces and safety thresholds for patients; (3) identifying tools to characterise actuator response to meet TGE shape and power requirements; (4) determining initial pressure control to achieve TGE and validating for safety through simulations and testing with a dummy finger; and (5) manufacturing and testing the actuator on the patient’s hand, followed by fine-tuning control. The orange text for each functional block denotes what this paper addresses, reflecting a limited scope of the functional blocks needed for the complete pipeline (shown in black).
Figure 3.
The OpenSim pipeline used to create torsional spring profile curves for fingers, drawing on muscle responses from healthy subjects. The pipeline aims to consider adjustments made to finger dimensions (model scaling), state of muscle contraction (activation energy), and joint rotation angle ranges (kinematic trajectory) to determine the loading at joints.
Figure 3.
The OpenSim pipeline used to create torsional spring profile curves for fingers, drawing on muscle responses from healthy subjects. The pipeline aims to consider adjustments made to finger dimensions (model scaling), state of muscle contraction (activation energy), and joint rotation angle ranges (kinematic trajectory) to determine the loading at joints.
Figure 4.
The finger’s muscle–tendon structure is used to perform flexion and extension motions of the finger. The tendon pull direction (TPD) acting over attachment points (AP1, AP2, AP3) illustrates the mechanism used to perform flexion/extension. (a) Anterior forearm muscles actuate the flexor digitorum superficialis and profundus tendons. Lumbrical muscles support flexion motion. (b) Posterior forearm muscles actuate the extensor digitorum tendons. The extensor hood mechanism supports the extensor digitorum tendons in performing finger extension.
Figure 4.
The finger’s muscle–tendon structure is used to perform flexion and extension motions of the finger. The tendon pull direction (TPD) acting over attachment points (AP1, AP2, AP3) illustrates the mechanism used to perform flexion/extension. (a) Anterior forearm muscles actuate the flexor digitorum superficialis and profundus tendons. Lumbrical muscles support flexion motion. (b) Posterior forearm muscles actuate the extensor digitorum tendons. The extensor hood mechanism supports the extensor digitorum tendons in performing finger extension.
Figure 5.
Middle finger depth (D3), breadth (B3) and length (L3) measurements for: the metacarpal (MC), finger phalanges (PP, MP, DP) and finger joints (MCP, PIP, DIP).
Figure 5.
Middle finger depth (D3), breadth (B3) and length (L3) measurements for: the metacarpal (MC), finger phalanges (PP, MP, DP) and finger joints (MCP, PIP, DIP).
Figure 6.
X-ray side view (a) and top view (b) superimposed over the ARMS wrist models bone data points used to derive measurements and placement of markers used for scaling. (a) Top view of the finger. The extrapolated surface region of the finger is outlined. Joint rotation points (MCP, PIP, DIP) and centre positions of the finger are shown, (b) Side view of the finger. The extrapolated surface region of the finger is outlined. Joint rotation points (MCP, PIP, DIP) and centre positions of the finger are shown.
Figure 6.
X-ray side view (a) and top view (b) superimposed over the ARMS wrist models bone data points used to derive measurements and placement of markers used for scaling. (a) Top view of the finger. The extrapolated surface region of the finger is outlined. Joint rotation points (MCP, PIP, DIP) and centre positions of the finger are shown, (b) Side view of the finger. The extrapolated surface region of the finger is outlined. Joint rotation points (MCP, PIP, DIP) and centre positions of the finger are shown.
Figure 7.
Moment vs. flexion response curves for CCD markers Lm, LM, Dm, DM, Bm, and DM at the MCP joint, illustrating: (a) passive MCP joint (AE = 0.01); (b) active MCP joint (AE = 1).
Figure 7.
Moment vs. flexion response curves for CCD markers Lm, LM, Dm, DM, Bm, and DM at the MCP joint, illustrating: (a) passive MCP joint (AE = 0.01); (b) active MCP joint (AE = 1).
Figure 8.
Expansion of block 3 from
Figure 2, detailing considerations for characterising actuator response: (3a) selecting actuator technology, (3b) defining actuator shape requirements (before and after pressurisation), (3c) determining finger dimensions and actuator-to-finger contact region, (3d) adjusting actuator unit dimensions, and (3e) configuring actuator unit combinations and groupings.
Figure 8.
Expansion of block 3 from
Figure 2, detailing considerations for characterising actuator response: (3a) selecting actuator technology, (3b) defining actuator shape requirements (before and after pressurisation), (3c) determining finger dimensions and actuator-to-finger contact region, (3d) adjusting actuator unit dimensions, and (3e) configuring actuator unit combinations and groupings.
Figure 9.
Orthographic PNA view showing the actuator’s top, front and side views. Dimensions considered include: width—PNA chamber width; ch_width—chamber air pocket width; air_vent—section width and height allowing airflow between chambers; ac_th_up—chamber top wall thickness; ac_th_for—chamber wall thickness along the actuator length; ends_ext—extra actuator front and end thickness; gap_height—the height of silicon layer between chambers; ch_height—chamber air pocket height; gap—the gap between chambers; dis_betw_ch—the distance between chambers; ch_depth—chamber air pocket depth along the PNA length; depth—PNA chamber depth. Section A-A depicted the actuator symmetry plane along its length. The definition of a single chamber is also shown.
Figure 9.
Orthographic PNA view showing the actuator’s top, front and side views. Dimensions considered include: width—PNA chamber width; ch_width—chamber air pocket width; air_vent—section width and height allowing airflow between chambers; ac_th_up—chamber top wall thickness; ac_th_for—chamber wall thickness along the actuator length; ends_ext—extra actuator front and end thickness; gap_height—the height of silicon layer between chambers; ch_height—chamber air pocket height; gap—the gap between chambers; dis_betw_ch—the distance between chambers; ch_depth—chamber air pocket depth along the PNA length; depth—PNA chamber depth. Section A-A depicted the actuator symmetry plane along its length. The definition of a single chamber is also shown.
Figure 10.
Parametrising the PNA actuator using reduced-order models. The response of the model is simplified to a bending angle () and unit length (). A fixed boundary condition is used for the actuator’s left nodes. A boundary condition only allowing rotation for the right nodes was used. To consider the bending moment, an additional fixed boundary condition was introduced to measure the reaction loads.
Figure 10.
Parametrising the PNA actuator using reduced-order models. The response of the model is simplified to a bending angle () and unit length (). A fixed boundary condition is used for the actuator’s left nodes. A boundary condition only allowing rotation for the right nodes was used. To consider the bending moment, an additional fixed boundary condition was introduced to measure the reaction loads.
Figure 11.
The actuators’ (
a) bending angle and (
b) bending moment observed for varied pressure gradients input to the top (
) and bottom (
) chambers defined in
Figure 10 for a 3D FEA model. A maximum pressure of 300
was considered. A Nearest Neighbour (NN) prediction model response fit is presented, predicting the results obtained from the FEA result sample points.
Figure 11.
The actuators’ (
a) bending angle and (
b) bending moment observed for varied pressure gradients input to the top (
) and bottom (
) chambers defined in
Figure 10 for a 3D FEA model. A maximum pressure of 300
was considered. A Nearest Neighbour (NN) prediction model response fit is presented, predicting the results obtained from the FEA result sample points.
Figure 12.
Bending angle comparison between the actuator’s true response and the predicted reduced-order model response. Three examples are shown for a pressure ratio of 0 using a top chamber pressure () of 60 kPa, 180 kPa and 300 kPa.
Figure 12.
Bending angle comparison between the actuator’s true response and the predicted reduced-order model response. Three examples are shown for a pressure ratio of 0 using a top chamber pressure () of 60 kPa, 180 kPa and 300 kPa.
Figure 13.
Experimental setup to measure moments. The actuator is clamped to a base behind the eight chambers to be pressurised. A tip force is measured using a scale to determine the moment generated by each PNA unit.
Figure 13.
Experimental setup to measure moments. The actuator is clamped to a base behind the eight chambers to be pressurised. A tip force is measured using a scale to determine the moment generated by each PNA unit.
Figure 14.
Experimental results comparison for the actuators’ (
a) bending angle and (
b) bending moment observed for varied pressure gradients input to the top (
) and bottom (
) chambers. The predicted 3D FEA reduced-order model results (
Figure 11) were compared to the actuators’ measured true response.
Figure 14.
Experimental results comparison for the actuators’ (
a) bending angle and (
b) bending moment observed for varied pressure gradients input to the top (
) and bottom (
) chambers. The predicted 3D FEA reduced-order model results (
Figure 11) were compared to the actuators’ measured true response.
Figure 15.
Parametrising the PNA actuator using reduced-order models. The response of the model is simplified to a bending angle () and unit length ().
Figure 15.
Parametrising the PNA actuator using reduced-order models. The response of the model is simplified to a bending angle () and unit length ().
Figure 16.
Actuator reduced-order model setup aimed at achieving (a) TGE1, (b) TGE2, (c) TGE3, (d) TGE4, (e) TGE5.
Figure 16.
Actuator reduced-order model setup aimed at achieving (a) TGE1, (b) TGE2, (c) TGE3, (d) TGE4, (e) TGE5.
Figure 17.
The 2D FEA bending angle results are used to relate between the 2D and 3D simulated results for the reduced-order bi-directional PNA chambers bending response. The 2D quadrilateral FEA mesh setup is presented (a) with the bending angle response fitted to a NN prediction model (b). Varied pressure gradients input to the top () and bottom () chambers are considered for a maximum pressure of 221 kPa determined to consider for bending angle ranged accounted by the reduced-order model fitted to the 3D results.
Figure 17.
The 2D FEA bending angle results are used to relate between the 2D and 3D simulated results for the reduced-order bi-directional PNA chambers bending response. The 2D quadrilateral FEA mesh setup is presented (a) with the bending angle response fitted to a NN prediction model (b). Varied pressure gradients input to the top () and bottom () chambers are considered for a maximum pressure of 221 kPa determined to consider for bending angle ranged accounted by the reduced-order model fitted to the 3D results.
Figure 18.
Planar analysis FEA setup for the cascaded PNA interacting with a finger (unaltered finger dimensions) showing: CMC actuator segment (), MCP joint rotation segment (), PIP joint rotation segment (), DIP joint rotation segment (); positioning of top and bottom actuator centred around a strain-limiting paper layer; materials definition consisting of silicone rubber, paper, bone and flesh; spring placement imitating straps to keep the finger attached to the actuator.
Figure 18.
Planar analysis FEA setup for the cascaded PNA interacting with a finger (unaltered finger dimensions) showing: CMC actuator segment (), MCP joint rotation segment (), PIP joint rotation segment (), DIP joint rotation segment (); positioning of top and bottom actuator centred around a strain-limiting paper layer; materials definition consisting of silicone rubber, paper, bone and flesh; spring placement imitating straps to keep the finger attached to the actuator.
Figure 19.
Setup of finger joint connections showing: overlapping nodes (Node A, Node B) located at the rotational joint position; rigid body element links connect to Nodes (A, B); spring connection between Nodes A and B showing high resistance in all translational directions between nodes used to mimic joint response.
Figure 19.
Setup of finger joint connections showing: overlapping nodes (Node A, Node B) located at the rotational joint position; rigid body element links connect to Nodes (A, B); spring connection between Nodes A and B showing high resistance in all translational directions between nodes used to mimic joint response.
Figure 20.
Cascaded PNA actuator control means via pressurising chambers with the initial starting position shown influenced by gravity.
Figure 20.
Cascaded PNA actuator control means via pressurising chambers with the initial starting position shown influenced by gravity.
Figure 21.
The bending response for pressure inputs determined by
Figure 9 is presented, validating the conceptualised actuator setup determined to achieve TGE using the reduced-order actuator model definition. TGE1, TGE2, and TGE3 were determined to be achieved, while TGE4 and TGE5 were unsuccessful in obtaining the kinematic orientation required to achieve TGE.
Figure 21.
The bending response for pressure inputs determined by
Figure 9 is presented, validating the conceptualised actuator setup determined to achieve TGE using the reduced-order actuator model definition. TGE1, TGE2, and TGE3 were determined to be achieved, while TGE4 and TGE5 were unsuccessful in obtaining the kinematic orientation required to achieve TGE.
Figure 22.
Stand-alone actuator bending comparison between the 2D and 3D simulations aimed at achieving TGE1, TGE2, and TGE3. The bending response when using the same pressure input specified by
Figure 9 for both the 2D and 3D simulation was initially compared. Whether a similar bending profile is achieved between the 2D and 3D FEA simulation was compared by adjusting the 3D simulations pressure input to that specified by
Table 8. A comparison was made between the manufactured actuators and the 3D simulated bending profiles.
Figure 22.
Stand-alone actuator bending comparison between the 2D and 3D simulations aimed at achieving TGE1, TGE2, and TGE3. The bending response when using the same pressure input specified by
Figure 9 for both the 2D and 3D simulation was initially compared. Whether a similar bending profile is achieved between the 2D and 3D FEA simulation was compared by adjusting the 3D simulations pressure input to that specified by
Table 8. A comparison was made between the manufactured actuators and the 3D simulated bending profiles.
Figure 23.
Dummy finger and actuator setup used to validate the simulated results, demonstrating the actuators’ capability to achieve the three target TGE (TGE1, TGE2, TGE3).
Figure 23.
Dummy finger and actuator setup used to validate the simulated results, demonstrating the actuators’ capability to achieve the three target TGE (TGE1, TGE2, TGE3).
Figure 24.
Setup used to measure spring force and lengths required to achieve different TGE.
Figure 24.
Setup used to measure spring force and lengths required to achieve different TGE.
Figure 25.
Setup to test for the bi-directional PNA interacting with a dummy finger. The Dyneema cord connected phalanges to a spring and stepper motor setup, controlling the reaction moment. TGE1 (straight extension) and TGE2 (tabletop) were determined to be achievable using higher pressures. TGE3 struggled to bend to the target angles.
Figure 25.
Setup to test for the bi-directional PNA interacting with a dummy finger. The Dyneema cord connected phalanges to a spring and stepper motor setup, controlling the reaction moment. TGE1 (straight extension) and TGE2 (tabletop) were determined to be achievable using higher pressures. TGE3 struggled to bend to the target angles.
Figure 26.
Side and top view for an adjusted finger model considering a parameter change ratio of 0.5 to finger depth, length and breadth according to the CCD design layout.
Figure 26.
Side and top view for an adjusted finger model considering a parameter change ratio of 0.5 to finger depth, length and breadth according to the CCD design layout.
Figure 27.
Setup to evaluate the design pipeline using reduced-order models to predict the actuator-finger response. The test involved a finger with altered dimensions (CCD parameter change = 0.5 for all dimensions). TGE1 and TGE2, identified as achievable from
Figure 25, are compared with the reduced-order model profiles.
Figure 27.
Setup to evaluate the design pipeline using reduced-order models to predict the actuator-finger response. The test involved a finger with altered dimensions (CCD parameter change = 0.5 for all dimensions). TGE1 and TGE2, identified as achievable from
Figure 25, are compared with the reduced-order model profiles.
Figure 28.
Proposed steps for adapting the design process to accommodate a patient’s entire hand for TGE include: (1) measuring the patient’s fingers (little, ring, middle, index); (2) applying the pipeline outlined
Figure 2 using the dimensions of a selected finger to determine the actuator and pressure control required for TGE; (3) repeating the pipeline steps for the remaining fingers; and (4) using the manufactured, customised rehabilitation glove to perform TGE exercises, with pressure control adjusted and calibrated for the patient’s hand.
Figure 28.
Proposed steps for adapting the design process to accommodate a patient’s entire hand for TGE include: (1) measuring the patient’s fingers (little, ring, middle, index); (2) applying the pipeline outlined
Figure 2 using the dimensions of a selected finger to determine the actuator and pressure control required for TGE; (3) repeating the pipeline steps for the remaining fingers; and (4) using the manufactured, customised rehabilitation glove to perform TGE exercises, with pressure control adjusted and calibrated for the patient’s hand.
Table 1.
Target tendon-gliding exercise joint positions showing: joint rotation angles in degrees for the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints needed to approximately orientate fingers for TGE1 to TGE5, as determined by
Figure 1.
Table 1.
Target tendon-gliding exercise joint positions showing: joint rotation angles in degrees for the metacarpophalangeal (MCP), proximal interphalangeal (PIP), and distal interphalangeal (DIP) joints needed to approximately orientate fingers for TGE1 to TGE5, as determined by
Figure 1.
Exercise | Tendon Gliding Exercises Joint Rotation Requirements (deg°) |
---|
MCP | PIP | DIP |
---|
TGE1 | 0° | 0° | 0° |
TGE2 | 90° | 0° | 0° |
TGE3 | 90° | 90° | 0° |
TGE4 | 90° | 100° | 80° |
TGE5 | 0° | 100° | 80° |
Table 2.
Middle finger depth (D3), breadth (B3) and dorsal length (L3) measurements for phalanges (PP, MP, DP) and joints (MCP, PIP, DIP). The mean, standard deviation (SD), and percentile values (5th = 5 percentile, 95th = 95 percentile) are presented [
12].
Table 2.
Middle finger depth (D3), breadth (B3) and dorsal length (L3) measurements for phalanges (PP, MP, DP) and joints (MCP, PIP, DIP). The mean, standard deviation (SD), and percentile values (5th = 5 percentile, 95th = 95 percentile) are presented [
12].
| Middle Finger Measurements (mm) |
---|
|
Females and Males Jointly
|
---|
Measure Code
|
Mean
|
SD
|
5th
|
95th
|
---|
D3DP | 11.8 | 1.52 | 10 | 15.0 |
D3DIP | 12.7 | 1.42 | 11 | 15.0 |
D3MP | 14.1 | 1.71 | 12 | 17.0 |
D3PIP | 16.6 | 1.66 | 14 | 20.0 |
D3PP | 17.3 | 2.00 | 14 | 20.1 |
D3MCP | 25.5 | 2.85 | 21 | 30 |
B3DP | 16.5 | 1.83 | 13 | 20.0 |
B3DIP | 16.8 | 1.62 | 14 | 20.0 |
B3MP | 17.6 | 1.99 | 14 | 21.0 |
B3PIP | 19.4 | 2.02 | 17 | 23.0 |
B3PP | 18.6 | 2.08 | 15 | 22.0 |
L3DP | 26.5 | 2.47 | 22 | 31.0 |
L3MP | 30.6 | 2.74 | 26 | 35.0 |
L3PP | 50.6 | 3.79 | 45 | 57.0 |
L3MC | 76.8 | 6.69 | 66 | 88.0 |
Table 3.
Details on CCD marker values input into OpenSim. The ratio multiplied by each finger measure is given, where two standard deviations multiplied by a scaling factor (the parameter change) are used to determine scaling values, which should be input into OpenSim for the ARMS wrist model. The metacarpal (MC) scaling values are shown for the ARMS wrist model local X, Y and Z axis scaling values.
Table 3.
Details on CCD marker values input into OpenSim. The ratio multiplied by each finger measure is given, where two standard deviations multiplied by a scaling factor (the parameter change) are used to determine scaling values, which should be input into OpenSim for the ARMS wrist model. The metacarpal (MC) scaling values are shown for the ARMS wrist model local X, Y and Z axis scaling values.
Marker Name | Parameter Change (Ratio) | OpenSim MC Scaling Values |
---|
Depth (D3) | Length (L3) | Breadth (B3) | X-Axis | Y-Axis | Z-Axis |
---|
D+L+B− | −0.7071 | +0.7071 | −0.7071 | 1.118 | 1.202 | 1.223 |
D+L+B+ | +0.7071 | +0.7071 | +0.7071 | 1.118 | 1.202 | 1.223 |
D−L+B− | −0.7071 | +0.7071 | −0.7071 | 1.12 | 1.202 | 1.056 |
Lm | 0 | −1 | 0 | 1.024 | 1.043 | 1.152 |
D+L−B+ | +0.7071 | −0.7071 | +0.7071 | 1.039 | 1.07 | 1.233 |
D+L−B− | +0.7071 | −0.7071 | −0.7071 | 1.039 | 1.07 | 1.233 |
Dm | −1 | 0 | 0 | 1.081 | 1.136 | 1.027 |
Bm | 0 | 0 | −1 | 1.079 | 1.136 | 1.145 |
Original | 0 | 0 | 0 | 1.079 | 1.136 | 1.145 |
BM | 0 | 0 | 1 | 1.079 | 1.136 | 1.145 |
D−L+B+ | −0.7071 | +0.7071 | +0.7071 | 1.12 | 1.202 | 1.056 |
DM | +1 | 0 | 0 | 1.078 | 1.136 | 1.263 |
D−L−B+ | −0.7071 | −0.7071 | +0.7071 | 1.041 | 1.07 | 1.067 |
D−L−B− | −0.7071 | −0.7071 | −0.7071 | 1.041 | 1.07 | 1.067 |
LM | 0 | 1 | 0 | 1.135 | 1.23 | 1.137 |
Table 4.
Details on CCD marker values input into OpenSim. The ratio multiplied by each finger measure is given, where two standard deviations multiplied by a scaling factor (the parameter change) are used to determine scaling values, which should be input into OpenSim for the ARMS wrist model. The scaling values for the phalanges (PP, MP, and DP) are shown for the ARMS wrist model local X, Y, and Z axis scaling values.
Table 4.
Details on CCD marker values input into OpenSim. The ratio multiplied by each finger measure is given, where two standard deviations multiplied by a scaling factor (the parameter change) are used to determine scaling values, which should be input into OpenSim for the ARMS wrist model. The scaling values for the phalanges (PP, MP, and DP) are shown for the ARMS wrist model local X, Y, and Z axis scaling values.
Marker Name | OpenSim PP Scaling Values | OpenSim MP Scaling Values | OpenSim DP Scaling Values |
---|
X-Axis | Y-Axis | Z-Axis | X-Axis | Y-Axis | Z-Axis | X-Axis | Y-Axis | Z-Axis |
---|
D+L+B− | 1.116 | 1.192 | 1.127 | 1.073 | 1.118 | 1.037 | 1.181 | 1.275 | 1.226 |
D+L+B+ | 1.184 | 1.192 | 1.127 | 1.14 | 1.118 | 1.107 | 1.24 | 1.275 | 1.226 |
D−L+B− | 1.116 | 1.192 | 1.001 | 1.073 | 1.118 | 1.037 | 1.181 | 1.275 | 1.164 |
Lm | 1.065 | 1.047 | 1.039 | 1.019 | 0.957 | 0.986 | 1.091 | 1.084 | 1.067 |
D+L−B+ | 1.114 | 1.072 | 1.106 | 1.068 | 0.985 | 1.035 | 1.141 | 1.117 | 1.12 |
D+L−B− | 1.045 | 1.072 | 1.106 | 1 | 0.985 | 1.035 | 1.082 | 1.117 | 1.12 |
Dm | 1.115 | 1.132 | 0.964 | 1.07 | 1.051 | 0.987 | 1.161 | 1.196 | 1.098 |
Bm | 1.066 | 1.132 | 1.053 | 1.022 | 1.052 | 1.036 | 1.12 | 1.196 | 1.142 |
Original | 1.115 | 1.132 | 1.053 | 1.07 | 1.051 | 1.036 | 1.161 | 1.196 | 1.142 |
BM | 1.163 | 1.132 | 1.053 | 1.118 | 1.051 | 1.036 | 1.202 | 1.196 | 1.142 |
D−L+B+ | 1.184 | 1.192 | 1.001 | 1.14 | 1.118 | 1.037 | 1.24 | 1.275 | 1.164 |
DM | 1.115 | 1.132 | 1.143 | 1.07 | 1.051 | 1.086 | 1.161 | 1.196 | 1.186 |
D−L−B+ | 1.114 | 1.072 | 0.98 | 1.068 | 0.985 | 0.965 | 1.14 | 1.117 | 1.058 |
D−L−B− | 1.045 | 1.072 | 0.98 | 1 | 0.985 | 0.965 | 1.082 | 1.117 | 1.058 |
LM | 1.165 | 1.217 | 1.068 | 1.122 | 1.146 | 1.087 | 1.231 | 1.308 | 1.218 |
Table 5.
Three-parameter Mooney–Rivlin material model parameters [
29] for Smooth-Sil 950.
Table 5.
Three-parameter Mooney–Rivlin material model parameters [
29] for Smooth-Sil 950.
| [Pa] | [Pa] | [Pa] |
---|
Mooney–Rivlin coefficients | 260,567.62 | 97,549.81 | 57,500.69 |
Table 6.
PNA parameters kept constant in
Figure 9.
Table 6.
PNA parameters kept constant in
Figure 9.
Actuator Dimensions | Actuator Dimensions |
---|
Parametric | Measure | Parametric | Measure |
width | 20 mm | ac_th_for | 2 mm |
height | 15 mm | ac_th_side | 3 mm |
ch_width | 14 mm | gap | 1 mm |
ch_height | 13 mm | air_vent | 2 mm |
ac_th_up | 2 mm | gap_height | 1 mm |
paper_width | 0.2 mm | ends_ext | 2 mm |
dis_betw_ch | 5 mm | bot_layer | 2 mm |
ch_depth | 2.8 mm | depth | 6.8 mm |
Table 7.
Target bending moments and angles for each actuator segment’s chambers (
,
,
,
) presented in
Figure 16.
Table 7.
Target bending moments and angles for each actuator segment’s chambers (
,
,
,
) presented in
Figure 16.
Reduced-Order Single Actuator Unit’s Moment and Bending Angle Requirements |
---|
TGE | Moment (Unit: N.m) | Bending Angle (Unit: deg°) |
---|
| | | | | | | |
---|
TGE1 | 6.67 × 10−5 | 6.67 × 10−5 | 1.70 × 10−4 | 1.52 × 10−4 | 0° | 0° | 0° | 0° |
TGE2 | 2.88 × 10−3 | 2.88 × 10−3 | −9.24 × 10−5 | 1.39 × 10−4 | 7.5° | 7° | −4.7°
| 0° |
TGE3 | 1.28 × 10−3 | 1.28 × 10−3 | 7.71 × 10−3 | −1.37 × 10−4 | 7.5° | 8° | 8° | 0° |
TGE4 | 1.15 × 10−3 | 1.15 × 10−3 | 0.011 | 4.84 × 10−4 | 7.5° | 8° | 8° | 8° |
TGE5 | 2.86 × 10−3 | 2.86 × 10−3 | 3.68 × 10−3 | 1.42 × 10−3 | 0° | 8° | 8° | 8° |
Table 8.
Target pressure control for actuator lengths given in
Figure 16 to achieve TGE using reduced-order models. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Table 8.
Target pressure control for actuator lengths given in
Figure 16 to achieve TGE using reduced-order models. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Exercises | Actuator Pressure Control Aimed at Achieving Tendon-Gliding Exercises (Units: kPa) |
---|
| | | | | | | |
TGE1 | 159.61 | 259.95 | 159.61 | 259.95 | 159.61 | 259.95 | 147.33 | 147.33 |
TGE2 | 286.29 | 0 | 286.29 | 0 | 0 | 217.53 | 186.96 | 186.96 |
TGE3 | 291.45 | 0 | 291.45 | 0 | 291.45 | 0 | 168.96 | 168.96 |
TGE4 | 291.84 | 0 | 291.84 | 0 | 291.84 | 0 | 291.84 | 0 |
TGE5 | 148.14 | 257.64 | 148.14 | 257.64 | 215.31 | 0 | 215.31 | 0 |
Table 9.
Adjusted pressure control from
Table 8 to consider for a 2D plane-strain actuator formulation. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Table 9.
Adjusted pressure control from
Table 8 to consider for a 2D plane-strain actuator formulation. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Exercises | Actuator Pressure Control Aimed at Achieving Tendon-Gliding Exercises (Units: kPa) |
---|
| | | | | | | |
---|
TGE1 | 73.94 | 128.54 | 73.94 | 128.54 | 73.94 | 128.54 | 73.94 | 73.94 |
TGE2 | 202.90 | 0.00 | 202.90 | 0.00 | 0.001 | 136.84 | 116.71 | 116.71 |
TGE3 | 210.56 | 0.00 | 210.56 | 0.00 | 210.56 | 0.00 | 121.12 | 121.12 |
TGE4 | 211.17 | 0.00 | 211.17 | 0.00 | 211.17 | 0.00 | 211.17 | 0.00 |
TGE5 | 75.70 | 131.60 | 75.70 | 131.60 | 131.60 | 0.00 | 131.60 | 0.00 |
Table 10.
Pressure settings used to achieve bending profiles for TGE as shown in
Figure 25. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Table 10.
Pressure settings used to achieve bending profiles for TGE as shown in
Figure 25. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Exercises | Actuator Pressure Control Used to Test Dummy Finger (Units: kPa) |
---|
| | | | | | | |
---|
TGE1 | 130 | 226 | 130 | 226 | 130 | 226 | 130 | 130 |
TGE2 | 265 | 0 | 265 | 0 | 0 | 200 | 182 | 182 |
TGE3 | 300 | 0 | 300 | 0 | 300 | 0 | 206 | 206 |
Table 11.
Pressure settings used to achieve bending profiles for TGE1 and TGE2 as shown in
Figure 27 for a finger with altered dimensions (CCD parameter change = 0.5 for all dimensions). The predicted response was obtained using the reduced-order model, while the actual response was the pressure readings obtained from the manufactured finger-actuator response. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Table 11.
Pressure settings used to achieve bending profiles for TGE1 and TGE2 as shown in
Figure 27 for a finger with altered dimensions (CCD parameter change = 0.5 for all dimensions). The predicted response was obtained using the reduced-order model, while the actual response was the pressure readings obtained from the manufactured finger-actuator response. The notation
indicates the pressure input for either the top (
T) or bottom (
B) chamber (
Y =
T or
B) for the actuator lengths
,
,
,
(
X =
CMC,
MCP,
PIP or
DIP).
Exercises | Actuator Pressure Control Used to Test Dummy Finger (Units: kPa) |
---|
| | | | | | | |
---|
TGE1 (predicted) | 148.31 | 265.31 | 148.31 | 265.31 | 148.31 | 265.31 | 158.78 | 158.78 |
TGE1 (actual) | 150 | 250 | 150 | 250 | 150 | 250 | 140 | 140 |
TGE2 (predicted) | 297.23 | 0 | 297.23 | 0 | 0 | 243.12 | 178.3 | 178.3 |
TGE2 (actual) | 290 | 0 | 290 | 0 | 0 | 236 | 182 | 182 |