stewart-simscape/kinematic-study.org

Kinematic Study of the Stewart Platform

• Functions
  • getMaxPositions
  • getMaxPureDisplacement

Functions

getMaxPositions

  function [X, Y, Z] = getMaxPositions(stewart)
      Leg = stewart.Leg;
      J = stewart.J;
      theta = linspace(0, 2*pi, 100);
      phi = linspace(-pi/2 , pi/2, 100);
      dmax = zeros(length(theta), length(phi));

      for i = 1:length(theta)
          for j = 1:length(phi)
              L = J*[cos(phi(j))*cos(theta(i)) cos(phi(j))*sin(theta(i)) sin(phi(j)) 0 0 0]';
              dmax(i, j) = Leg.stroke/max(abs(L));
          end
      end

      X = dmax.*cos(repmat(phi,length(theta),1)).*cos(repmat(theta,length(phi),1))';
      Y = dmax.*cos(repmat(phi,length(theta),1)).*sin(repmat(theta,length(phi),1))';
      Z = dmax.*sin(repmat(phi,length(theta),1));
  end

getMaxPureDisplacement

  function [max_disp] = getMaxPureDisplacement(Leg, J)
      max_disp = zeros(6, 1);
      max_disp(1) = Leg.stroke/max(abs(J*[1 0 0 0 0 0]'));
      max_disp(2) = Leg.stroke/max(abs(J*[0 1 0 0 0 0]'));
      max_disp(3) = Leg.stroke/max(abs(J*[0 0 1 0 0 0]'));
      max_disp(4) = Leg.stroke/max(abs(J*[0 0 0 1 0 0]'));
      max_disp(5) = Leg.stroke/max(abs(J*[0 0 0 0 1 0]'));
      max_disp(6) = Leg.stroke/max(abs(J*[0 0 0 0 0 1]'));
  end