/IMPDISP
Block Format Keyword Defines imposed displacements on a group of nodes.
Format
(1)  (2)  (3)  (4)  (5)  (6)  (7)  (8)  (9)  (10) 

/IMPDISP/impdisp_ID/unit_ID  
impdisp_title  
fct_ID_{T}  Dir  Skew_ID  sens_ID  grnd_ID  icoor  
Ascale_{x}  Fscale_{Y}  T_{start}  T_{stop} 
Definition
Field  Contents  SI Unit Example 

impdisp_ID  Imposed displacement block
identifier. (Integer, maximum 10 digits) 

unit_ID  Unit Identifier. (Integer, maximum 10 digits) 

impdisp_title  Imposed displacement block
title. (Character, maximum 100 characters) 

fct_ID_{T}  Time function
identifier. (Integer) 

Dir  Direction: X, Y, and Z in
translation; XX, YY, and ZZ in rotation. (Text) 

Skew_ID  Skew
identifier. (Integer) 

sens_ID  Sensor identifier.
(Integer) 

grnd_ID  Node group on which the
imposed displacement is applied. (Integer) 

icoor  Coordinate system usage
type.
(Integer) 

Ascale_{x}  Abscissa (time) scale
factor for
fct_ID_{T}. Default = 1.0 (Real) 
$\left[\text{s}\right]$ 
Fscale_{Y}  Ordinate (displacement)
scale factor for
fct_ID_{T}. Default = 1.0 (Real) 
$\left[\text{m}\right]$ or $\left[\text{rad}\right]$ 
T_{start}  Start
time. (Real) 
$\left[\text{s}\right]$ 
T_{stop}  Stop time. Default = 10^{30} (Real) 
$\left[\text{s}\right]$ 
Comments
 The displacement direction must be right justified in the ten characters of field number 2.
 If T_{start} and T_{stop} are specified, the displacement is imposed between these times, but the time versus displacement function is not shifted to begin at T_{start}.
 When a sensor is defined sens_ID, the imposed displacement is applied at the time of sensor activation and the function is shifted by the sensor activation time.
 When a sensor sens_ID is used with T_{start} and T_{stop}, the imposed displacement will only occur if the sensor activation time occurs between T_{start} and T_{stop}.
 The
Ascale_{X} and
Fscale_{Y} are used to scale
the abscissa (time) and ordinate (displacement or angle).The actual load function value is calculated as:
(1) $$\mathrm{F}(t)=Fscal{e}_{y}\cdot {\mathrm{f}}_{T}\left(\frac{t}{Ascal{e}_{x}}\right)$$Where, ${\mathrm{f}}_{T}$ is the function of fct_ID_{T}.
 If icoor=1, the directions X, Y, and Z (resp. XX, YY, and ZZ) refer to translations along (resp. rotations around) the radial direction (r), azimuthal angular direction ( $\theta $ ) and longitudinal direction (Z) (/SKEW/FIX).
 If icoor=1 when
imposing the translational displacement in the radial, resp. the azimuthal
direction, the displacement of the node is set so that:
(2) $${\delta}_{r}\left(t\right)={\displaystyle \int \dot{r}dt=}\text{\hspace{0.17em}}Fscal{e}_{y}\cdot {\mathrm{f}}_{T}\left(\frac{t}{Ascal{e}_{x}}\right)$$(3) $$resp.\text{\hspace{0.17em}}\theta ={\displaystyle \int \dot{\theta}dt=}\text{\hspace{0.17em}}Fscal{e}_{y}\cdot {\mathrm{f}}_{T}\left(\frac{t}{Ascal{e}_{x}}\right)$$Where, ${\mathrm{f}}_{T}$ is the function of fct_ID_{T}.