diff options
Diffstat (limited to 'uav_model.m')
| -rw-r--r-- | uav_model.m | 66 |
1 files changed, 55 insertions, 11 deletions
diff --git a/uav_model.m b/uav_model.m index 747f1b7..4fddae9 100644 --- a/uav_model.m +++ b/uav_model.m @@ -1,6 +1,8 @@ % Compute models for Ducted Fan VTOL micro-UAV for given set of parameters. % % Copyright (C) 2024, Naoki Sean Pross, ETH Zürich. +% This work is distributed under a permissive license, see LICENSE.txt +% % This function generates three models: % % * A non-linear symbolic model (cannot be used directly). @@ -219,10 +221,9 @@ D = zeros(12, 5); [ny, ~] = size(C); % Create state space object -sys = ss(A, B, C, D); - -% T = params.actuators.MeasurementDelay; -% sys = ss(A, B, C, D, 'OutputDelay', T); +T = params.measurements.SensorFusionDelay; +n = params.linearization.PadeApproxOrder; +sys = minreal(pade(ss(A, B, C, D, 'OutputDelay', T), n)); % Save linearized dynamics (numerical) model.linear = struct(... @@ -263,7 +264,7 @@ if rank(Wc) < nx end end -% Check system observability / detectability +% Check system observability / detectability Wo = obsv(sys); if rank(Wo) < nx fprintf('Linearized system has %d unobservable states!\n', ... @@ -283,11 +284,23 @@ if rank(Wo) < nx fprintf('Linearized system has %d undetectable modes!\n', ... undetectable); else - fprintf('However, it is detectable.') + fprintf('However, it is detectable.\n') end end % ------------------------------------------------------------------------ +% Model actuators + +% TODO: better model, this was tuned "by looking" +w = 4 * params.actuators.ServoNominalAngularVelocity; +zeta = .7; +G_servo = tf(w^2, [1, 2 * zeta * w, w^2]); +% figure; step(G_servo * pi / 3); grid on; +G_prop = tf(1,1); + +model.actuators = struct('FlapServo', G_servo, 'ThrustPropeller', G_prop); + +% ------------------------------------------------------------------------ % Add uncertainties using SIMULINK model % Load simulink model with uncertainties and pass in parameters @@ -303,9 +316,25 @@ hws.assignin('uncert', uncert); ulmod = linmod('uav_model_uncertain'); usys = ss(ulmod.a, ulmod.b, ulmod.c, ulmod.d); +% Specify uncertainty block structure for mussv command +blk_stab = [ + 4, 0; % alpha + 1, 0; % omega + 12, 12; % state +]; + +blk_perf = [ + 4, 0; % alpha + 1, 0; % omega + 3, 3; % position + 3, 3; % velocity +]; + % Save uncertain model model.uncertain = struct(... 'Simulink', ulmod, ... + 'BlockStructure', blk_stab, ... + 'BlockStructurePerf', blk_perf, ... 'StateSpace', usys ... ); @@ -324,14 +353,29 @@ model.uncertain = struct(... % Function make_idx(start, size) is defined below. model.uncertain.index = struct(... 'InputUncertain', make_idx( 1, 17), ... % 'v' inputs - 'InputDisturbance', make_idx(18, 12), ... % 'w' inputs for noise - 'InputReference', make_idx(30, 12), ... % 'w' inputs for reference - 'InputNominal', make_idx(42, 5), ... % 'u' inputs + 'InputDisturbance', make_idx(18, 7), ... % 'w' inputs for noise + 'InputReference', make_idx(25, 3), ... % 'w' inputs for reference + 'InputExogenous', make_idx(18, 10), ... % 'w' inputs (all of them) + 'InputNominal', make_idx(28, 5), ... % 'u' inputs 'OutputUncertain', make_idx( 1, 17), ... % 'z' outputs - 'OutputError', make_idx(18, 17), ... % 'e' outputs - 'OutputNominal', make_idx(35, 12) ... % 'y' outputs + 'OutputError', make_idx(18, 14), ... % 'e' outputs + 'OutputNominal', make_idx(32, 12), ... % 'y' outputs + 'OutputPlots', make_idx(44, 10) ... % 'p' outputs for plots in closed loop ); +idx = model.uncertain.index; + +% Number of inputs +model.uncertain.Nv = max(size(idx.InputUncertain)); +model.uncertain.Nr = max(size(idx.InputReference)); +model.uncertain.Nw = max(size(idx.InputExogenous)); +model.uncertain.Nu = max(size(idx.InputNominal)); + +% Number of outputs +model.uncertain.Nz = max(size(idx.OutputUncertain)); +model.uncertain.Ne = max(size(idx.OutputError)); +model.uncertain.Ny = max(size(idx.OutputNominal)); + % ------------------------------------------------------------------------ % Check properties of uncertain model |