Files
miSim/@miSim/constrainMotion.m
2026-01-07 12:41:22 -08:00

153 lines
6.1 KiB
Matlab

function [obj] = constrainMotion(obj)
arguments (Input)
obj (1, 1) {mustBeA(obj, 'miSim')};
end
arguments (Output)
obj (1, 1) {mustBeA(obj, 'miSim')};
end
if size(obj.agents, 1) < 2
nAAPairs = 0;
else
nAAPairs = nchoosek(size(obj.agents, 1), 2); % unique agent/agent pairs
end
agents = [obj.agents{:}];
v = reshape(([agents.pos] - [agents.lastPos])./obj.timestep, 3, size(obj.agents, 1))';
% Initialize QP based on number of agents and obstacles
nAOPairs = size(obj.agents, 1) * size(obj.obstacles, 1); % unique agent/obstacle pairs
nADPairs = size(obj.agents, 1) * 5; % agents x (4 walls + 1 ceiling)
nLNAPairs = sum(obj.constraintAdjacencyMatrix, 'all') - size(obj.agents, 1);
total = nAAPairs + nAOPairs + nADPairs + nLNAPairs;
kk = 1;
A = zeros(total, 3 * size(obj.agents, 1));
b = zeros(total, 1);
% Set up collision avoidance constraints
h = NaN(size(obj.agents, 1));
h(logical(eye(size(obj.agents, 1)))) = 0; % self value is 0
for ii = 1:(size(obj.agents, 1) - 1)
for jj = (ii + 1):size(obj.agents, 1)
h(ii, jj) = norm(agents(ii).pos - agents(jj).pos)^2 - (agents(ii).collisionGeometry.radius + agents(jj).collisionGeometry.radius)^2;
h(jj, ii) = h(ii, jj);
A(kk, (3 * ii - 2):(3 * ii)) = -2 * (agents(ii).pos - agents(jj).pos);
A(kk, (3 * jj - 2):(3 * jj)) = -A(kk, (3 * ii - 2):(3 * ii));
b(kk) = obj.barrierGain * h(ii, jj)^3;
kk = kk + 1;
end
end
hObs = NaN(size(obj.agents, 1), size(obj.obstacles, 1));
% Set up obstacle avoidance constraints
for ii = 1:size(obj.agents, 1)
for jj = 1:size(obj.obstacles, 1)
% find closest position to agent on/in obstacle
cPos = obj.obstacles{jj}.closestToPoint(agents(ii).pos);
hObs(ii, jj) = dot(agents(ii).pos - cPos, agents(ii).pos - cPos) - agents(ii).collisionGeometry.radius^2;
A(kk, (3 * ii - 2):(3 * ii)) = -2 * (agents(ii).pos - cPos);
b(kk) = obj.barrierGain * hObs(ii, jj)^3;
kk = kk + 1;
end
end
% Set up domain constraints (walls and ceiling only)
% Floor constraint is implicit with an obstacle corresponding to the
% minimum allowed altitude, but I included it anyways
for ii = 1:size(obj.agents, 1)
% X minimum
h_xMin = (agents(ii).pos(1) - obj.domain.minCorner(1)) - agents(ii).collisionGeometry.radius;
A(kk, (3 * ii - 2):(3 * ii)) = [-1, 0, 0];
b(kk) = obj.barrierGain * h_xMin^3;
kk = kk + 1;
% X maximum
h_xMax = (obj.domain.maxCorner(1) - agents(ii).pos(1)) - agents(ii).collisionGeometry.radius;
A(kk, (3 * ii - 2):(3 * ii)) = [1, 0, 0];
b(kk) = obj.barrierGain * h_xMax^3;
kk = kk + 1;
% Y minimum
h_yMin = (agents(ii).pos(2) - obj.domain.minCorner(2)) - agents(ii).collisionGeometry.radius;
A(kk, (3 * ii - 2):(3 * ii)) = [0, -1, 0];
b(kk) = obj.barrierGain * h_yMin^3;
kk = kk + 1;
% Y maximum
h_yMax = (obj.domain.maxCorner(2) - agents(ii).pos(2)) - agents(ii).collisionGeometry.radius;
A(kk, (3 * ii - 2):(3 * ii)) = [0, 1, 0];
b(kk) = obj.barrierGain * h_yMax^3;
kk = kk + 1;
% Z minimum
h_zMin = (agents(ii).pos(3) - obj.domain.minCorner(3)) - agents(ii).collisionGeometry.radius;
A(kk, (3 * ii - 2):(3 * ii)) = [0, 0, -1];
b(kk) = obj.barrierGain * h_zMin^3;
kk = kk + 1;
% Z maximum
h_zMax = (obj.domain.maxCorner(2) - agents(ii).pos(2)) - agents(ii).collisionGeometry.radius;
A(kk, (3 * ii - 2):(3 * ii)) = [0, 0, 1];
b(kk) = obj.barrierGain * h_zMax^3;
kk = kk + 1;
end
% Save off h function values (ignoring network constraints which may evolve in time)
obj.h(:, obj.timestepIndex) = [h(triu(true(size(obj.agents, 1)), 1)); reshape(hObs, [], 1); h_xMin; h_xMax; h_yMin; h_yMax; h_zMin; h_zMax;];
% Add communication network constraints
hComms = NaN(size(obj.agents, 1));
hComms(logical(eye(size(obj.agents, 1)))) = 0;
for ii = 1:(size(obj.agents, 1) - 1)
for jj = (ii + 1):size(obj.agents, 1)
if obj.constraintAdjacencyMatrix(ii, jj)
hComms(ii, jj) = min([obj.agents{ii}.commsGeometry.radius, obj.agents{jj}.commsGeometry.radius])^2 - norm(agents(ii).pos - agents(jj).pos)^2;
A(kk, (3 * ii - 2):(3 * ii)) = 2 * (agents(ii).pos - agents(jj).pos);
A(kk, (3 * jj - 2):(3 * jj)) = -A(kk, (3 * ii - 2):(3 * ii));
b(kk) = obj.barrierGain * hComms(ii, jj);
% dVNominal = v(ii, 1:3) - v(jj, 1:3); % nominal velocities
% h_dot_nom = -2 * (agents(ii).pos - agents(jj).pos) * dVNominal';
% b(kk) = -h_dot_nom + obj.barrierGain * hComms(ii, jj)^3;
kk = kk + 1;
end
end
end
% Solve QP program generated earlier
vhat = reshape(v', 3 * size(obj.agents, 1), 1);
H = 2 * eye(3 * size(obj.agents, 1));
f = -2 * vhat;
% Update solution based on constraints
assert(size(A,2) == size(H,1))
assert(size(A,1) == size(b,1))
assert(size(H,1) == length(f))
opt = optimoptions('quadprog', 'Display', 'off');
[vNew, ~, exitflag, m] = quadprog(sparse(H), double(f), A, b, [],[], [], [], [], opt);
assert(exitflag == 1, sprintf('quadprog failure... %s%s', newline, m.message));
vNew = reshape(vNew, 3, size(obj.agents, 1))';
if exitflag <= 0
warning("QP failed, continuing with unconstrained solution...")
vNew = v;
end
% Update the "next position" that was previously set by unconstrained
% GA using the constrained solution produced here
for ii = 1:size(vNew, 1)
obj.agents{ii}.pos = obj.agents{ii}.lastPos + vNew(ii, :) * obj.timestep;
end
% Here we run this at the simulation level, but in reality there is no
% parent level, so this would be run independently on each agent.
% Running at the simulation level is just meant to simplify the
% simulation
end