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| author | ziejd2 | 2017-09-28 15:04:40 -0500 |
|---|---|---|
| committer | ziejd2 | 2017-09-28 15:04:40 -0500 |
| commit | 8070dc963753142bb86c4ed698d91fd623ed28e7 (patch) | |
| tree | d0f6dd8fc46a49b819aa55c1a90faa14d8448883 /sourcecodes/bnt-master/BNT/examples/dynamic/SLAM/Old/offline_loopy_slam.m | |
| parent | 7cc31810d53176e805532b2789955f4eedbce6bb (diff) | |
| download | BNW-8070dc963753142bb86c4ed698d91fd623ed28e7.tar.gz | |
BNW using Octave instead of Matlab.
This version of BNW should perform the same as the original version. The only difference is that it uses Octave instead of Matlab when running BayesNet Toolbox during parameter learning. I am calling this BNW_1.02. It can be accessed at: compbio.uthsc.edu/BNW_1.02
Diffstat (limited to 'sourcecodes/bnt-master/BNT/examples/dynamic/SLAM/Old/offline_loopy_slam.m')
| -rw-r--r-- | sourcecodes/bnt-master/BNT/examples/dynamic/SLAM/Old/offline_loopy_slam.m | 231 |
1 files changed, 231 insertions, 0 deletions
diff --git a/sourcecodes/bnt-master/BNT/examples/dynamic/SLAM/Old/offline_loopy_slam.m b/sourcecodes/bnt-master/BNT/examples/dynamic/SLAM/Old/offline_loopy_slam.m new file mode 100644 index 00000000..377a4659 --- /dev/null +++ b/sourcecodes/bnt-master/BNT/examples/dynamic/SLAM/Old/offline_loopy_slam.m @@ -0,0 +1,231 @@ +% We navigate a robot around a square using a fixed control policy and no noise. +% We assume the robot observes the relative distance to the nearest landmark. +% Everything is linear-Gaussian. + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +% Create toy data set + +seed = 0; +rand('state', seed); +randn('state', seed); + +if 1 + T = 20; + ctrl_signal = [repmat([1 0]', 1, T/4) repmat([0 1]', 1, T/4) ... + repmat([-1 0]', 1, T/4) repmat([0 -1]', 1, T/4)]; +else + T = 5; + ctrl_signal = repmat([1 0]', 1, T); +end + +nlandmarks = 4; +true_landmark_pos = [1 1; + 4 1; + 4 4; + 1 4]'; +init_robot_pos = [0 0]'; + +true_robot_pos = zeros(2, T); +true_data_assoc = zeros(1, T); +true_rel_dist = zeros(2, T); +for t=1:T + if t>1 + true_robot_pos(:,t) = true_robot_pos(:,t-1) + ctrl_signal(:,t); + else + true_robot_pos(:,t) = init_robot_pos + ctrl_signal(:,t); + end + nn = argmin(dist2(true_robot_pos(:,t)', true_landmark_pos')); + %nn = t; % observe 1, 2, 3 + true_data_assoc(t) = nn; + true_rel_dist(:,t) = true_landmark_pos(:, nn) - true_robot_pos(:,t); +end + +figure(1); +%clf; +hold on +%plot(true_landmark_pos(1,:), true_landmark_pos(2,:), '*'); +for i=1:nlandmarks + text(true_landmark_pos(1,i), true_landmark_pos(2,i), sprintf('L%d',i)); +end +for t=1:T + text(true_robot_pos(1,t), true_robot_pos(2,t), sprintf('%d',t)); +end +hold off +axis([-1 6 -1 6]) + +R = 1e-3*eye(2); % noise added to observation +Q = 1e-3*eye(2); % noise added to robot motion + +% Create data set +obs_noise_seq = sample_gaussian([0 0]', R, T)'; +obs_rel_pos = true_rel_dist + obs_noise_seq; +%obs_rel_pos = true_rel_dist; + + +%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% +% Create params for inference + +% X(t) = A X(t-1) + B U(t) + noise(Q) + +% [L1] = [1 ] * [L1] + [0] * Ut + [0 ] +% [L2] [ 1 ] [L2] [0] [ 0 ] +% [R ]t [ 1] [R ]t-1 [1] [ Q] + +% Y(t)|S(t)=s = C(s) X(t) + noise(R) +% Yt|St=1 = [1 0 -1] * [L1] + R +% [L2] +% [R ] + +% Create indices into block structure +bs = 2*ones(1, nlandmarks+1); % sizes of blocks in state space +robot_block = block(nlandmarks+1, bs); +for i=1:nlandmarks + landmark_block(:,i) = block(i, bs)'; +end +Xsz = 2*(nlandmarks+1); % 2 values for each landmark plus robot +Ysz = 2; % observe relative location +Usz = 2; % input is (dx, dy) + + +% create block-diagonal trans matrix for each switch +A = zeros(Xsz, Xsz); +for i=1:nlandmarks + bi = landmark_block(:,i); + A(bi, bi) = eye(2); +end +bi = robot_block; +A(bi, bi) = eye(2); +A = repmat(A, [1 1 nlandmarks]); % same for all switch values + +% create block-diagonal system cov + + +Qbig = zeros(Xsz, Xsz); +bi = robot_block; +Qbig(bi,bi) = Q; % only add noise to robot motion +Qbig = repmat(Qbig, [1 1 nlandmarks]); + +% create input matrix +B = zeros(Xsz, Usz); +B(robot_block,:) = eye(2); % only add input to robot position +B = repmat(B, [1 1 nlandmarks]); + +% create observation matrix for each value of the switch node +% C(:,:,i) = (0 ... I ... -I) where the I is in the i'th posn. +% This computes L(i) - R +C = zeros(Ysz, Xsz, nlandmarks); +for i=1:nlandmarks + C(:, landmark_block(:,i), i) = eye(2); + C(:, robot_block, i) = -eye(2); +end + +% create observation cov for each value of the switch node +Rbig = repmat(R, [1 1 nlandmarks]); + +% initial conditions +init_x = zeros(Xsz, 1); +init_v = zeros(Xsz, Xsz); +bi = robot_block; +init_x(bi) = init_robot_pos; +init_V(bi, bi) = 1e-5*eye(2); % very sure of robot posn +for i=1:nlandmarks + bi = landmark_block(:,i); + init_V(bi,bi)= 1e5*eye(2); % very uncertain of landmark psosns + %init_x(bi) = true_landmark_pos(:,i); + %init_V(bi,bi)= 1e-5*eye(2); % very sure of landmark psosns +end + +%%%%%%%%%%%%%%%%%%%%% +% Inference +if 1 +[xsmooth, Vsmooth] = kalman_smoother(obs_rel_pos, A, C, Qbig, Rbig, init_x, init_V, ... + 'model', true_data_assoc, 'u', ctrl_signal, 'B', B); + +est_robot_pos = xsmooth(robot_block, :); +est_robot_pos_cov = Vsmooth(robot_block, robot_block, :); + +for i=1:nlandmarks + bi = landmark_block(:,i); + est_landmark_pos(:,i) = xsmooth(bi, T); + est_landmark_pos_cov(:,:,i) = Vsmooth(bi, bi, T); +end +end + + +if 0 +figure(1); hold on +for i=1:nlandmarks + h=plotgauss2d(est_landmark_pos(:,i), est_landmark_pos_cov(:,:,i)); + set(h, 'color', 'r') +end +hold off + +hold on +for t=1:T + h=plotgauss2d(est_robot_pos(:,t), est_robot_pos_cov(:,:,t)); + set(h,'color','r') + h=text(est_robot_pos(1,t), est_robot_pos(2,2), sprintf('R%d', t)); + set(h,'color','r') +end +hold off +end + + +if 0 +figure(3) +if 0 + for t=1:T + imagesc(inv(Vsmooth(:,:,t))) + colorbar + fprintf('t=%d; press key to continue\n', t); + pause + end +else + for t=1:T + subplot(5,4,t) + imagesc(inv(Vsmooth(:,:,t))) + end +end +end + + + + + +%%%%%%%%%%%%%%%%% +% DBN inference + +if 1 + [bnet, Unode, Snode, Lnodes, Rnode, Ynode, Lsnode] = ... + mk_gmux_robot_dbn(nlandmarks, Q, R, init_x, init_V, robot_block, landmark_block); + engine = pearl_unrolled_dbn_inf_engine(bnet, 'max_iter', 50, 'filename', ... + '/home/eecs/murphyk/matlab/loopyslam.txt'); +else + [bnet, Unode, Snode, Lnodes, Rnode, Ynode] = ... + mk_gmux2_robot_dbn(nlandmarks, Q, R, init_x, init_V, robot_block, landmark_block); + engine = jtree_dbn_inf_engine(bnet); +end + +nnodes = bnet.nnodes_per_slice; +evidence = cell(nnodes, T); +evidence(Ynode, :) = num2cell(obs_rel_pos, 1); +evidence(Unode, :) = num2cell(ctrl_signal, 1); +evidence(Snode, :) = num2cell(true_data_assoc); + + +[engine, ll, niter] = enter_evidence(engine, evidence); +niter + +loopy_est_robot_pos = zeros(2, T); +for t=1:T + m = marginal_nodes(engine, Rnode, t); + loopy_est_robot_pos(:,t) = m.mu; +end + +for i=1:nlandmarks + m = marginal_nodes(engine, Lnodes(i), T); + loopy_est_landmark_pos(:,i) = m.mu; + loopy_est_landmark_pos_cov(:,:,i) = m.Sigma; +end + + |
