LTPDA Toolbox™

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Method ssm/ssm

  SSM statespace model class constructor.
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  DESCRIPTION: SSM statespace model class constructor.
 
  CONSTRUCTORS:
 
        s = ssm()            - creates an empty statespace model
        s = ssm('a1.xml')    - creates a new statespace model by loading the
                               object from disk.
        s = ssm('a1.mat')    - creates a new statespace model by loading the
                               object from disk.
        a = ssm(plist)       - creates a statespace model from the description
                               given in the parameter list
        a = ssm(struct)      - creates a statespace model from the
                               structure returned by struct(ssm).
 
 
  EXAMPLES:
 
  1) Construct an SSM object by description:
 
                  name = 'sys';
                  statenames = {'ss1' 'ss2' 'ss3'};
                  inputnames = {'input1' 'input2' 'input3'};
                  outputnames = {'output1' 'output2' 'output3'};
                  timestep = 0;
                  params = plist({'omega', 'system frequency'}, 2);
                  amats = cell(3, 3);
                  bmats = cell(3, 3);
                  cmats = cell(3, 3);
                  dmats = cell(3, 3);
                  amats{1, 1} = -(sym('omega'));
                  amats{2, 2} = -2;
                  amats{3, 3} = -3*eye(2);
                  amats{3, 1} = [-1;-3];
                  bmats{1, 1} = 1;
                  bmats{2, 2} = 2;
                  bmats{3, 3} = 3*eye(2);
                  cmats{1, 1} = 1;
                  cmats{2, 2} = 1;
                  cmats{3, 3} = eye(2);
                  dmats{1, 3} = [6 6];
                  dmats{2, 1} = 6;
                  dmats{3, 2} = [6;6];
                  sys = ssm(plist( ...
                    'amats', amats, 'bmats', bmats, 'cmats', cmats, 'dmats', dmats, ...
                    'timestep', timestep, 'name', name, 'params', params, ...
                    'statenames', statenames, 'inputnames', inputnames, 'outputnames', outputnames ));
 
 
      A shortcut (incomplete) syntax is :
                 sys = ssm( amats, bmats, cmats, dmats, timestep, name, params, ...
                            statenames, inputnames, outputnames )
      Also :
                 sys = ssm(miirObject);
                 sys = ssm(rationalObject);
                 sys = ssm(parfracObject);
 
      More complete call
                 % here computation of the system's matrices, declaration
                 % of parameters, some symbolic may be stored in the user
                 % plist
                 sys = struct
                 SMD_W = 0.2;  SMD_C = 0.5; SMD_S1 = 0; SMD_S2 = 0; SMD_B = 1; SMD_D1 = 0;
                 sys.params = plist;
 
 
                 sys.amats    = {[0 1 ; -SMD_W*SMD_W -2*SMD_C*SMD_W]};
                 sys.cmats    = {[1+SMD_S1 SMD_S2]};
                 sys.bmats    = {[0;SMD_B] [0 0; 1 0]};
                 sys.dmats    = {SMD_D1 [0 1]};
 
                 sys.timestep = 0;
 
                 sys.name = 'SRPINGMASSDAMPER';
                 sys.description = 'standard spring-mass-damper test system';
 
                 inputnames    = {'CMD' 'DIST_SMD'};
                 inputdescription = {'force noise' 'observation noise'};
                 inputvarnames = {{'F'} {'F' 'S'}};
                 inputvarunits = {unit('kg m s^-2') [unit('kg m s^-2') unit('m')]};
                 inputvardescription = [];
 
                 ssnames    = {'SMD'};
                 ssdescription = {'TM position and speed'};
                 ssvarnames = {{'x' 'xdot'}};
                 ssvarunits={[unit('m') unit('m s^-1')]};
                 ssvardescription = [];
 
                 outputnames    = {'SMD'};
                 outputdescription = {'observed position'};
                 outputvarnames ={{'OBS'}};
                 outputvarunits={unit('m')};
                 outputvardescription = [];
 
                 %% Build ssmblocks
                 sys.inputs = ssmblock.makeBlocksWithData(inputnames, inputdescription, inputvarnames, inputvarunits, inputvardescription);
                 sys.outputs = ssmblock.makeBlocksWithData(outputnames, outputdescription, outputvarnames, outputvarunits, outputvardescription);
                 sys.states =  ssmblock.makeBlocksWithData(ssnames, ssdescription, ssvarnames, ssvarunits, ssvardescription);
                 %% plist constructors
                 sys = ssm(plist( ...
                   'amats',sys.amats, 'bmats', sys.bmats, 'cmats', sys.cmats, 'dmats', sys.dmats, ...
                   'timestep', 0, 'name', sys.name, 'inputs', sys.inputs, ...
                   'states', sys.states, 'outputs', sys.outputs));
 
 
  Parameters Description
 
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Parameter Description

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Method: ssm/rebuild

Method: ssm/ssm2miir

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