Wheel Odometry

Objective

Efficiency of the wheel odometry computation process of the robot was evaluated after integration of both high-level and low-lovel systems consisting of the main computational subsystems Hub motor interface, Wheel velocity estimation, Forward kinematics, Wheel odometry computation by measuring the tolerance of the robot current position (x, y)

Procedure

  1. Turn on manual robot control using teleop_twist_keyboard

  2. Control the robot to move forward in the x-axis of the odom frame to 10 cm, 20 cm, 30 cm, 40 cm, and 50 cm for 10 times

  3. Control the robot to move forward in the y-axis of the odom frame to 10 cm, 20 cm, 30 cm, 40 cm, and 50 cm for 10 times

  4. Take the value (x, y) from topic: wheel/odometry then calculate tolerance compared to the actual distance traveled

  5. Evaluate the efficiency of the wheel odometry process

Results

X-axis of odom frame

Displacement(cm)

Trial 1

Trial 2

Trial 3

Trial 4

Trial 5

Trial 6

Trial 7

Trial 8

Trial 9

Trial 10

Error

10

16.301

15.666

14.385

15.109

14.806

13.824

15.326

14.754

12.798

14.759

6.301

20

24.148

25.648

24.634

25.608

23.975

24.009

27.571

26.895

24.896

25.131

7.571

30

33.171

34.045

37.269

38.018

37.849

37.198

37.445

34.058

35.816

34.092

8.018

40

41.120

45.389

47.653

47.928

44.554

48.872

46.679

47.987

49.983

41.452

9.983

50

58.673

60.765

58.292

58.718

59.240

59.934

59.685

54.303

58.012

54.778

10.765

X-axis analysis

Wheel odometry calculations can give the robot position in the x-axis of the odom frame with a maximum tolerance of 10.765 cm within a displacement of 50 cm.

Y-axis of odom frame

Displacement(cm)

Trial 1

Trial 2

Trial 3

Trial 4

Trial 5

Trial 6

Trial 7

Trial 8

Trial 9

Trial 10

Error

10

13.053

13.918

10.839

12.218

14.411

18.399

13.068

13.633

10.771

12.512

8.399

20

24.618

26.900

21.512

21.728

28.835

27.147

27.358

25.806

26.171

28.651

8.835

30

35.500

39.764

35.651

36.811

37.807

41.850

38.883

33.653

37.776

38.319

11.850

40

48.260

47.996

44.945

46.897

51.780

48.071

53.822

45.850

48.139

50.887

13.822

50

62.130

60.422

58.491

60.030

63.659

65.620

64.561

58.032

67.028

67.626

17.028

Y-axis analysis

Wheel odometry calculations can give the robot position in the x-axis of the odom frame with a maximum tolerance of 17.028 cm within a displacement of 50 cm.