Design, Test, and Evaluation of a High Powered 4 DOF Prosthetic Leg for Transfemoral Amputees

Greczek, Brandyn Thomas

Author	Greczek, Brandyn Thomas
Title	Design, Test, and Evaluation of a High Powered 4 DOF Prosthetic Leg for Transfemoral Amputees
URL	http://hdl.handle.net/10919/90791
Publication Date	2019
Date Accessioned	2019-07-02 08:00:41
Degree	MS
Discipline/Department	Mechanical Engineering
Degree Level	masters
University/Publisher	Virginia Tech
Abstract	A high powered prosthesis for transfemoral amputees is presented in this paper. Four control mechanisms, three of which are in series with springs to reduce the total power requirement of the motors, are used on the prosthesis to provide power to all motions of the leg. The prosthesis is capable of providing powered motion for knee and ankle pitch, ankle roll, and ankle yaw, i.e. ankle rotation from side to side. The prosthesis was designed to handle a variety of activities including, but not limited to, walking, running, and stair climbing.
Subjects/Keywords	Transfemoral; Transtibial; Prosthesis; High Power
Contributors	Asbeck, Alan T. (committeechair); Leonessa, Alexander (committee member); Nussbaum, Maury A. (committee member)
Rights	In Copyright http://rightsstatements.org/vocab/InC/1.0/
Country of Publication	us
Record ID	handle:10919/90791
Repository	vt
Date Retrieved	2020-11-25
Date Indexed	2020-12-04
Grantor	Virginia Polytechnic Institute and State University
Issued Date	2019-07-01 00:00:00
Note	[degree] Master of Science;

Sample Images | Cited Works

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[43] C. Knabe, R. Griffin, J. Burton, G. Cantor-Cooke, L. Dantanarayana, G. Day, O. Ebeling-Koning, E. Hahn, M. Hopkins, J. Neal, J. Newton, C. Nogales, V. Orekhov, J. Peterson, M. Rouleau, J. Seminatore, Y. Sung, J. Webb, N. Wittenstein, J. Ziglar, A. Leonessa, B. Lattimer, and T. Furukawa, “Team VALOR’s ESCHER: A Novel Electromechanical Biped for the DARPA Robotics Challenge,” Journal of Field Robotics, vol. 34, no. 5, 2017. Appendices Appendix A Spreadsheets Leaf Spring Calculations Spreadsheet A.1 Chapter A. Spreadsheets Case 2 Span (mm) Width (mm) Thickness (mm) 8.5 Arm length(mm) Youngs Modulus E 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 1.138E+11 Moment of Inertia 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.70667E-09 1.62133E-09 2.55885E-09 Force 97 A.1. Leaf Spring Calculations Spreadsheet Slope (rad) 0.054371705 0.059808875 0.065246046 0.070683216 0.076120387 0.081557557 0.086994728 0.092431898 0.097869069 0.103306239 0.108743409 0.11418058 0.131159814 0.16226095 Deflection at R (Rx) mm 0.006041301 0.006645431 0.007249561 0.007853691 0.008457821 0.009061951 0.009666081 0.010270211 0.010874341 0.011478471 0.012082601 0.012686731 0.01399038 0.019538923 Deflection at R (Ry) mm 1.359292619 1.644744069 1.957381371 2.297204525 2.664213533 3.058408392 3.479789104 3.928355668 4.404108084 4.907046353 5.437170475 5.994480448 7.213789774 10.95261415 Deflection at Q (Qx) mm 2.614597413 2.875760208 3.136838183 3.397823639 3.658708879 3.919486207 4.180147932 4.440686366 4.701093825 4.961362628 5.221485098 5.481453565 6.553194511 8.097032393 Deflection at Q (Qy) mm 1.430225916 1.730568918 2.059514247 2.417061421 2.803209916 3.217959166 3.661308564 4.13325746 4.633805163 5.16295094 5.720694016 6.307033575 7.643246008 11.60938666 Chapter A. Spreadsheets Absolute Deflection at Q (mm) 2.980212376 3.35631726 3.752512854 4.169819108 4.609136198 5.071255596 5.556871164 6.066589868 6.60094186 7.160389761 7.745337091 8.356135811 10.06794755 14.15414399 Bending Stress at R (Mpa) 542.7631579 581.3148789 Hobby Motors Selection Spreadsheet A.2 A.2. Hobby Motors Selection Spreadsheet Quick motor calculations *Choosing motors using a maximum current draw of 30A from motor controller 44.4 60.8 20.944 0.048 29.7 83.499 125.8 1.670 17.802 0.056 29.7 Alien 6374 Outrunner brushless motor 170KV 3200W 72.812 170.496 8524.8 1.456 20.106 0.050 44.4 29.3 Turnigy Aerodrive SK3 6374-192kv Brushless Outrunner Motor 139.798 88.8 2.796 10.472 0.095 44.4 29.3 60.148 174.64 1.203 24.714 0.040 29.7 Turnigy Aerodrive SK3 5065-236kv Brushless Outrunner Motor 44.359 236.8 0.887 33.510 0.030 29.7 Turnigy Aerodrive SK3 5065-320kv Brushless Outrunner Motor 48.948 214.6 0.979 30.369 0.033 29.7 0.00170 0.0247 0.00415 0.0304 $167.18 Yes 0.00227 0.0246 $56.86 No 0.00167 0.0181 $56.86 No 0.00155 0.0155 $75.83 Yes Turnigy G160 Brushless Outrunner 290kv (160 Glow) 50.265 0.020 1.419 £ 65.00 $79.96 Yes 9235-100KV Turnigy Multistar Brushless MultiRotor Motor Kv [rad/Volt-sec] Ke [N-m/Amp] = 1/Kv 1.210 70.975 Custom GFORCE G180 BRUSHLESS OUTRUNNER MOTOR (C6374200KV) No-load Speed [RPM] Torque [Nm] 60.490 426.24 $85.00 62.8 Yes RotorStar Brushless Outrunner Helicopter 4962-480kv (700/.90 size heli) Gear Ratio: [] Torque * Gear Ratio [Nm] Speed after gear ratio [rpm] $84.70 Yes Motor Voltage [V] Motor Power [W] Kv [rpm/V] Motor Current [A] Price Weight (g) Diameter (mm) In Stock 0.00189 0.0226 0.00223 0.00270 0.0247 Torque to Weight (Nm/g) Torque to Diameter (Nm/mm) Volume (mm^2) Chapter A. Spreadsheets 29.7 54.454 0.018 44.4 49.5 1.014 29.322 0.034 29.7 Turnigy Aerodrive SK3 5055-280kv Brushless Outrunner Motor 7.689 355.2 0.154 125.664 0.008 14.8 19.3 NTM Prop Drive Series 28-26A 1200kv / 286w (short shaft version) 4.802 636.4 0.096 225.147 0.004 14.8 21.6 Multistar 22062150KV 3~4S 320w FPV Racing Motor "The Baby Beast" 37.089 162.208 8110.4 0.742 28.693 0.035 29.6 21.3 Multistar Elite 5010274KV Multi-Rotor Motor 60.782 102.12 1.216 24.086 0.042 22.2 29.3 6340230KV Turnigy Multistar Brushless Multi-Rotor Motors Set (2 pcs) 11.459 0.229 130.900 0.008 30.0 $55.02 Yes 37.089 162.208 8110.4 0.742 28.693 0.035 29.6 21.3 Multistar Elite 5010274KV Multi-Rotor Motor 0.00473 0.0194 $31.86 Yes 26.250 138.24 0.525 50.265 0.020 14.4 26.4 4108480KV Turnigy Multistar 22 Pole Brushless Multi-Rotor Motor With Extra Long Leads 0.00198 0.0055 $39.99 Yes 16.131 236.8 0.323 41.888 0.024 29.6 13.5 0.00225 0.0062 $39.99 Yes 18.373 171.52 0.367 28.065 0.036 10.3 MT28 19.897 0.050 0.910 50.696 207.2 $172.09 Yes 0.00352 0.0128 Multistar Elite 3508268KV High Voltage Endurance Motor 1.494 45.496 461.76 $49.23 No 0.00378 0.0193 NTM Prop Drive Series 35-42A 1250Kv 600W 74.710 140.6 $75.62 Yes 0.00275 0.0207 KEDA 63-64 190KV Brushless Outrunner 10S 2000W $44.52 Yes 0.00231 0.0186 RotorStar Brushless Outrunner Helicopter 4956-520kv (600/.50 size heli) 0.00223 0.0237 101 A.2. Hobby Motors Selection Spreadsheet $39.99 Yes 15.405 247.95 12397.5 0.308 49.742 0.020 26.1 15.3 0.00262 0.0072 $39.99 Yes 21.373 118.4 0.427 41.888 0.024 14.8 17.9 Mystery Brushless Motor 5010-400 Kv 0.00189 0.0052 102 A.3 Chapter A. Spreadsheets Ball Screw Selection Spreadsheet A.3. Ball Screw Selection Spreadsheet Ball Screw Pre-gearing Rotational Speed (rpm) Linear displacement (m/s) Linear Force (N) No Gearing 1:1.25 geared 1:1.5 geared 1:2 geared 1:2.5 geared 1:3 geared 1:3.5 geared 1:4 geared Lever arm length (m) No Gearing 1.1000 2286.0 0.8800 2857.5 0.7333 3429.0 0.5500 4572.0 0.4400 5715.0 0.3667 6858.0 0.3143 8001.0 0.2750 9144.1 Peak Velocity (rad/s) 0.02 0.021 0.022 0.023 0.024 0.025 0.026 0.027 0.028 0.029 0.03 0.031 0.032 0.033 0.034 0.035 0.036 0.037 0.038 0.039 0.04 0.041 0.042 0.043 0.044 0.045 0.046 0.047 0.048 0.049 0.05 0.051 0.052 0.053 0.054 0.055 0.056 0.057 0.058 0.059 0.06 55.00 52.38 50.00 47.83 45.83 44.00 42.31 40.74 39.29 37.93 36.67 35.48 34.38 33.33 32.35 31.43 30.56 29.73 28.95 28.21 27.50 26.83 26.19 25.58 25.00 24.44 23.91 23.40 22.92 22.45 22.00 21.57 21.15 20.75 20.37 20.00 19.64 19.30 18.97 18.64 18.33 1:1.25 geared 1:1.5 geared 1:2 geared 44.00 41.90 40.00 38.26 36.67 35.20 33.85 32.59 31.43 30.34 29.33 28.39 27.50 26.67 25.88 25.14 24.44 23.78 23.16 22.56 22.00 21.46 20.95 20.47 20.00 19.56 19.13 18.72 18.33 17.96 17.60 17.25 16.92 16.60 16.30 16.00 15.71 15.44 15.17 14.92 14.67 36.67 34.92 33.33 31.88 30.56 29.33 28.21 27.16 26.19 25.29 24.44 23.66 22.92 22.22 21.57 20.95 20.37 19.82 19.30 18.80 18.33 17.89 17.46 17.05 16.67 16.30 15.94 15.60 15.28 14.97 14.67 14.38 14.10 13.84 13.58 13.33 13.10 12.87 12.64 12.43 12.22 27.50 26.19 25.00 23.91 22.92 22.00 21.15 20.37 19.64 18.97 18.33 17.74 17.19 16.67 16.18 15.71 15.28 14.86 14.47 14.10 13.75 13.41 13.10 12.79 12.50 12.22 11.96 11.70 11.46 11.22 11.00 10.78 10.58 10.38 10.19 10.00 9.82 9.65 9.48 9.32 9.17 1:2.5 geared 1:3 geared 22.00 20.95 20.00 19.13 18.33 17.60 16.92 16.30 15.71 15.17 14.67 14.19 13.75 13.33 12.94 12.57 12.22 11.89 11.58 11.28 11.00 10.73 10.48 10.23 10.00 9.78 9.57 9.36 9.17 8.98 8.80 8.63 8.46 8.30 8.15 8.00 7.86 7.72 7.59 7.46 7.33 18.33 17.46 16.67 15.94 15.28 14.67 14.10 13.58 13.10 12.64 12.22 11.83 11.46 11.11 10.78 10.48 10.19 9.91 9.65 9.40 9.17 8.94 8.73 8.53 8.33 8.15 7.97 7.80 7.64 7.48 7.33 7.19 7.05 6.92 6.79 6.67 6.55 6.43 6.32 6.21 6.11 1:3.5 geared 1:4 geared 15.71 14.97 14.29 13.66 13.10 12.57 12.09 11.64 11.22 10.84 10.48 10.14 9.82 9.52 9.24 8.98 8.73 8.49 8.27 8.06 7.86 7.67 7.48 7.31 7.14 6.98 6.83 6.69 6.55 6.41 6.29 6.16 6.04 5.93 5.82 5.71 5.61 5.51 5.42 5.33 5.24 13.75 13.10 12.50 11.96 11.46 11.00 10.58 10.19 9.82 9.48 9.17 8.87 8.59 8.33 8.09 7.86 7.64 7.43 7.24 7.05 6.88 6.71 6.55 6.40 6.25 6.11 5.98 5.85 5.73 5.61 5.50 5.39 5.29 5.19 5.09 5.00 4.91 4.82 4.74 4.66 4.58 Peak Torque (Nm) No Gearing Lever arm length (m) 0.02 0.021 0.022 0.023 0.024 0.025 0.026 0.027 0.028 0.029 0.03 0.031 0.032 0.033 0.034 45.72 48.01 50.29 52.58 54.86 57.15 59.44 61.72 64.01 66.29 68.58 70.87 73.15 75.44 77.72 1:1.25 geared 1:1.5 geared 1:2 geared 57.15 60.01 62.87 65.72 68.58 71.44 74.30 77.15 80.01 82.87 85.73 88.58 91.44 94.30 97.16 68.58 72.01 75.44 78.87 82.30 85.73 89.15 92.58 96.01 99.44 102.87 106.30 109.73 113.16 116.59 91.44 96.01 100.58 105.16 109.73 114.30 118.87 123.44 128.02 132.59 137.16 141.73 146.30 150.88 155.45 1:2.5 geared 1:3 geared 114.30 120.02 125.73 131.45 137.16 142.88 148.59 154.31 160.02 165.74 171.45 177.17 182.88 188.60 194.31 137.16 144.02 150.88 157.73 164.59 171.45 178.31 185.17 192.03 198.88 205.74 212.60 219.46 226.32 233.17 1:3.5 geared 1:4 geared 160.02 168.02 176.02 184.02 192.03 200.03 208.03 216.03 224.03 232.03 240.03 248.03 256.03 264.03 272.04 182.88 192.03 201.17 210.31 219.46 228.60 237.75 246.89 256.03 265.18 274.32 283.47 292.61 301.75 310.90 104 Chapter A. Spreadsheets 0.035 0.036 0.037 0.038 0.039 0.04 0.041 0.042 0.043 0.044 0.045 0.046 0.047 0.048 0.049 0.05 0.051 0.052 0.053 0.054 0.055 0.056 0.057 0.058 0.059 0.06 80.01 82.30 84.58 86.87 89.15 91.44 93.73 96.01 98.30 100.58 102.87 105.16 107.44 109.73 112.01 114.30 116.59 118.87 121.16 123.44 125.73 128.02 130.30 132.59 134.87 137.16 100.01 102.87 105.73 108.59 111.44 114.30 117.16 120.02 122.87 125.73 128.59 131.45 134.30 137.16 140.02 142.88 145.73 148.59 151.45 154.31 157.16 160.02 162.88 165.74 168.59 171.45 120.02 123.44 126.87 130.30 133.73 137.16 140.59 144.02 147.45 150.88 154.31 157.73 161.16 164.59 168.02 171.45 174.88 178.31 181.74 185.17 188.60 192.03 195.45 198.88 202.31 205.74 160.02 164.59 169.17 173.74 178.31 182.88 187.45 192.03 196.60 201.17 205.74 210.31 214.89 219.46 224.03 228.60 233.17 237.75 242.32 246.89 251.46 256.03 260.61 265.18 269.75 274.32 200.03 205.74 211.46 217.17 222.89 228.60 234.32 240.03 245.75 251.46 257.18 262.89 268.61 274.32 280.04 285.75 291.47 297.18 302.90 308.61 314.33 320.04 325.76 331.47 337.19 342.90 240.03 246.89 253.75 260.61 267.46 274.32 281.18 288.04 294.90 301.75 308.61 315.47 322.33 329.19 336.04 342.90 349.76 356.62 363.48 370.33 377.19 384.05 390.91 397.77 404.62 411.48 280.04 288.04 296.04 304.04 312.04 320.04 328.04 336.04 344.05 352.05 360.05 368.05 376.05 384.05 392.05 400.05 408.05 416.05 424.06 432.06 440.06 448.06 456.06 464.06 472.06 480.06 320.04 329.19 338.33 347.47 356.62 365.76 374.91 384.05 393.19 402.34 411.48 420.63 429.77 438.91 448.06 457.20 466.35 475.49 484.63 493.78 502.92 512.07 521.21 530.36 539.50 548.64 A.3. Ball Screw Selection Spreadsheet Appendix B Gait Cycle Plots B.1. 0.447 m/s (1 mph) Walking Gait B.1 0.447 m/s (1 mph) Walking Gait Ankle Pitch Angle [deg] Knee Pitch Angle [deg] Prosthesis Human -10 -20 -30 Gait [%] Figure B.1: Top: Knee pitch angle vs. gait percent. Bottom: Ankle pitch angle vs. gait percent Knee Moment [N-m] -20 Prosthesis Human -40 Ankle Moment [N-m] -20 Gait [%] Figure B.2: Top: Knee joint moment vs. gait percent. Bottom: Ankle joint moment vs. gait percent. 108 B.2 Chapter B. Gait Cycle Plots 0.67 m/s (1.5 mph) Walking Gait with Mode Transitions Knee Pitch Angle [deg] Mode 2 Mode 1 Prosthesis Human Mode 3 Mode 4 Knee Moment [N-m] -20 -40 Gait [%] Figure B.3: Top: Knee pitch angle vs. gait percent. Bottom: Knee joint moment vs. gait percent. The transitions are given by the vertical black lines and indicate when each gait mode was entered. Ankle Pitch Angle [deg] Mode 1 Mode 2 Mode 3 Mode 4 -10 Prosthesis Human -20 Ankle Moment [N-m] -20 Gait [%] Figure B.4: Top: Ankle pitch angle vs. gait percent. Bottom: Ankle joint moment vs. gait percent. The transitions are given by the vertical black lines and indicate when each gait mode was entered.

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