Skip to main content

Table 2 RMS values of the constraining forces and moments during AP tests

From: Evaluation of three force-position hybrid control methods for a robot-based biological joint-testing system

Control method

0° Knee flexion

30° Knee flexion

Force (N)

Moment (Nm)

Angle (deg)

Force (N)

Moment (Nm)

Angle (deg)

PD

LM

VV

IE

FE

PD

LM

VV

IE

FE

Total

 CT

38.4

(1.4)

29.4

(0.7)

0.97

(0.02)

0.26

(0.03)

0.72

(0.01)

0.11

(0.00)

35.4

(1.2)

17.1

(0.4)

0.82

(0.04)

0.26

(0.02)

1.13

(0.00)

0.11

(0.00)

 FPH

4.6

(0.4)

8.5

(0.4)

0.33

(0.00)

0.20

(0.03)

0.75

(0.02)

0.14

(0.03)

7.5

(0.3)

11.5

(0.4)

0.45

(0.00)

0.23

(0.01)

1.00

(0.02)

0.40

(0.03)

 FPA

2.4

(0.3)

1.4

(0.2)

0.07

(0.00)

0.11

(0.02)

0.51

(0.04)

0.89

(0.03)

2.8

(0.2)

2.1

(0.5)

0.11

(0.01)

0.15

(0.02)

0.82

(0.03)

1.29

(0.01)

 FPHFM

2.2

(0.2)

1.4

(0.3)

0.07

(0.03)

0.09

(0.02)

0.50

(0.05)

1.36

(0.19)

2.3

(0.2)

2.2

(0.3)

0.12

(0.00)

0.14

(0.01)

0.95

(0.02)

1.55

(0.02)

Anterior

 CT

48.0

(3.2)

48.0

(0.6)

1.56

(0.06)

0.31

(0.08)

0.54

(0.02)

0.11

(0.00)

34.1

(1.0)

32.7

(0.1)

1.50

(0.01)

0.16

(0.03)

0.78

(0.00)

0.11

(0.00)

 FPH

5.8

(0.7)

9.2

(0.7)

0.34

(0.02)

0.27

(0.05)

0.60

(0.07)

0.11

(0.03)

9.8

(1.2)

11.5

(0.4)

0.65

(0.01)

0.22

(0.02)

1.09

(0.02)

0.27

(0.03)

 FPA

2.4

(0.2)

1.5

(0.2)

0.07

(0.03)

0.09

(0.03)

0.36

(0.12)

0.46

(0.03)

3.6

(0.2)

2.1

(0.4)

0.12

(0.01)

0.15

(0.01)

0.91

(0.03)

1.20

(0.01)

 FPHFM

2.4

(0.2)

1.6

(0.5)

0.07

(0.03)

0.05

(0.02)

0.36

(0.04)

0.65

(0.19)

3.2

(0.1)

2.3

(0.4)

0.13

(0.01)

0.11

(0.01)

1.04

(0.03)

1.44

(0.02)

Posterior

 CT

35.2

(0.7)

4.4

(1.4)

0.41

(0.03)

0.17

(0.01)

1.14

(0.01)

0.11

(0.00)

35.7

(1.5)

5.4

(1.5)

0.26

(0.01)

0.33

(0.02)

1.41

(0.00)

0.11

(0.00)

 FPH

3.5

(0.1)

7.9

(0.2)

0.31

(0.01)

0.19

(0.02)

0.83

(0.01)

0.17

(0.03)

5.6

(0.3)

11.5

(0.1)

0.27

(0.00)

0.24

(0.01)

0.99

(0.02)

0.46

(0.03)

 FPA

2.4

(0.4)

1.3

(0.1)

0.07

(0.01)

0.13

(0.03)

0.65

(0.02)

1.18

(0.03)

2.3

(0.2)

2.2

(0.7)

0.10

(0.01)

0.15

(0.02)

0.71

(0.04)

1.33

(0.01)

 FPHFM

1.9

(0.2)

1.2

(0.2)

0.07

(0.03)

0.14

(0.03)

0.64

(0.05)

1.82

(0.19)

2.2

(0.3)

2.1

(0.3)

0.11

(0.01)

0.15

(0.01)

0.93

(0.02)

1.57

(0.02)

  1. Means (standard deviations) of the RMS values of the constraining forces (PD, ML) and moments (VV, IE) during AP tests of the knee at 0° and 30° flexion during the Constrained Test (CT), and unconstrained tests using Force-Position Hybrid control (FPH), Force-Position Alternate control (FPA), and Force-Position Hybrid control & Force-Moment control (FPHFM). As expected, CT needed the largest constraining forces and moments. For unconstrained tests, FPHFM and FPA achieved much smaller constraining forces and moments than FPH. For both 0° and 30° flexion, most of the constraining forces and moments during anterior tests were larger than those during posterior tests for all methods. The FE moments required to maintain the knee flexion angle are also provided
Back to article page

BioMedical Engineering OnLine

ISSN: 1475-925X

Contact us