Analog Data Processing with

BioProc3

Part ThreeImpact, Work and Force

Analysis Techniques

Force Transducer Calibration orEMG to Isometric Force Relationships

• use Pearson Correlation from Correlation menu• after correlation and regression coefficients are computed you

are prompted to apply one of the regression equations to the original data

• plot relationship with X-Y plot• use Scaling menu from Analysis menu to scale data to any

units`

force

raw EMG

LE-EMG

Force platform analyses

• use submenu Analyze Force Plate Data from Analysis menu• two plates can be combined (Combine Two Plates)• impulse computed (from integration statistics)• changes in centres of gravity estimated (Centre of Gravity)

Centre of gravity calculations

• requires subject to have static initial conditions• subject’s feet must be on one force platform or the data from

two force platforms must be combined• can compute 2D or 3D takeoff velocities, height after takeoff,

work done, power and lowest and highest positions during stance period

• high-pass filtering reduces drift for horizontal dimensions

Angular Impulse

• use Work or Angular Impulse Analysis from Integration Statics submenu of Analysis menu

• requires data file that contains moments (from Vicon or Visual3D ASCII export)

• moments must be in the first half of the data file, second half may contain powers

External, Internal and Total Work

• use Work or Angular Impulse Analysis from Integration Statics submenu of Analysis menu

• requires data file that contains moment powers (from Vicon or Visual3D ASCII export)

• powers must be in first half or all of the data file• average work, sum of positive and negative work and external,

internal and total mechanical work done are computed for each axis

• sums for each axis and total for all axes are also computed• calculates percent contributions for each moment

Moment Power Analysis (Work Bursts)

• use Moment Power Analysis from Integration Statics submenu of Analysis menu

• requires data file that contains moment powers (from Vicon or Visual3D ASCII export)

• computes work bursts and peak moments and powers whenever power changes from positive to negative or moment changes from positive to negative

• set a threshold to eliminate small bursts of power

Impact (GSI and HIC) Analyses

• use GSI and HIC (Impacts) from Integration Statics submenu of Analysis menu

• needs one channel of acceleration data scaled to g’s or m/s2

• second channel may contain triggering information (no longer used)

• computes Gadd Severity Index for head impacts only (i.e., uses a2.5)

• average acceleration, A-3 and HIC, integral, delta g and time to peak acceleration

• HIC is only done for the maximum allowable time interval