Measurment technology

Question 1

list the four key steps in 3D marker reconstruction.

Answer 1

1. Marker detection
2. Camera calibration
3. Marker tracking
4. 3D reconstruction

Question 2

What would be the best technology to use when measuring rear-leg kinematics of a dog jumping over hurdles

Answer 2

High-Speed Video Analysis: High-speed cameras can capture detailed video footage of the jumping motion, allowing for frame-by-frame analysis of the athlete’s technique.

Question 3

List the four main direct kinematics measurement systems

Answer 3

1) Inertial measurement units
2) Motion capture systems
3) Force plates
4) Electromyography (EMG’s)

Question 4

What quantities do IMU’s measure

Answer 4

• Acceleration
• angular velocities
• orientation

Question 5

What quantities do Motion capture systems measure?

Answer 5

• 3D positions
• Joint angles
• linear and angular velocities

Question 6

What quantities do force plates measure?

Answer 6

• ground reaction forces
• centre of pressure

Question 7

What quantities do EMG’s measure?

Answer 7

• muscle activation

Question 8

Provide a recommendation as to whether surface EMG or intramuscular EMG is more suitable for measuring vastus medialis activation

Answer 8

Surface EMG because:
1) Non-invasive: practical and easy to use
2) Whole muscle activity assessment: Since the vastus medialis is a relatively large muscle, surface EMG can provide a representative measure of its overall activation.

Question 9

Explain any 3 steps of EMG processing, and explain what each step accomplishes

Answer 9

1) Filtering: used to remove unwanted noise and artifacts from the EMG signal.
2) Rectification: converts the EMG signal into its absolute value or rectified form.
3) Smoothing: techniques, such as moving average or digital filtering, are applied to reduce the high-frequency fluctuations in the rectified signal.