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Fix std::normal_distribution when stdev is zero #73

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Merged
fmrico merged 2 commits into from
Jul 23, 2026
Merged

Fix std::normal_distribution when stdev is zero #73

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248aadb
Fix std::normal_distribution when stdev is zero
fmrico Jul 23, 2026
44a788f
Avoid creating objects every loop cycle
fmrico Jul 23, 2026
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28 changes: 15 additions & 13 deletions localizers/easynav_costmap_localizer/src/easynav_costmap_localizer/AMCLLocalizer.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -242,9 +242,9 @@ AMCLLocalizer::on_initialize()
RCLCPP_INFO(node->get_logger(), "at position (%lf, %lf, %lf) std_dev [%lf, %lf]",
x_init, y_init, yaw_init, std_dev_xy, std_dev_yaw);

std::normal_distribution<double> noise_x(x_init, std_dev_xy);
std::normal_distribution<double> noise_y(y_init, std_dev_xy);
std::normal_distribution<double> noise_yaw(yaw_init, std_dev_yaw);
std::normal_distribution<double> noise_x(x_init, std::max(std_dev_xy, 1e-12));
std::normal_distribution<double> noise_y(y_init, std::max(std_dev_xy, 1e-12));
std::normal_distribution<double> noise_yaw(yaw_init, std::max(std_dev_yaw, 1e-12));

particles_.resize(num_particles);
for (auto & p : particles_) {
Expand Down Expand Up @@ -430,7 +430,7 @@ AMCLLocalizer::init_pose_callback(
yaw_stddev = std::max(yaw_stddev, min_noise_yaw_);

std::normal_distribution<double> standard_normal(0.0, 1.0);
std::normal_distribution<double> yaw_noise(0.0, yaw_stddev);
std::normal_distribution<double> yaw_noise(0.0, std::max(yaw_stddev, 1e-12));

const std::size_t N = particles_.size();

Expand Down Expand Up @@ -545,15 +545,17 @@ AMCLLocalizer::predict([[maybe_unused]] NavState & nav_state)
double rot_len = std::abs(yaw);


for (auto & p : particles_) {
std::normal_distribution<double> noise_dx(0.0, std::abs(dx) * noise_translation_);
std::normal_distribution<double> noise_dy(0.0, std::abs(dy) * noise_translation_);
std::normal_distribution<double> noise_dz(0.0, std::abs(dz) * noise_translation_);

std::normal_distribution<double> noise_yaw(
0.0,
rot_len * noise_rotation_ + trans_len * noise_translation_to_rotation_);
std::normal_distribution<double> noise_dx(
0.0, std::max(std::abs(dx) * noise_translation_, 1e-12));
std::normal_distribution<double> noise_dy(
0.0, std::max(std::abs(dy) * noise_translation_, 1e-12));
std::normal_distribution<double> noise_dz(
0.0, std::max(std::abs(dz) * noise_translation_, 1e-12));
std::normal_distribution<double> noise_yaw(
0.0,
std::max(rot_len * noise_rotation_ + trans_len * noise_translation_to_rotation_, 1e-12));

for (auto & p : particles_) {
tf2::Vector3 noisy_translation(
dx + noise_dx(rng_),
dy + noise_dy(rng_),
Expand Down Expand Up @@ -680,7 +682,7 @@ AMCLLocalizer::reseed()
double yaw_variance = computeYawVariance(particles_, 0, N_top);
double yaw_stddev = std::sqrt(yaw_variance);
std::normal_distribution<double> yaw_noise(0.0, std::max(yaw_stddev, min_noise_yaw_));
std::normal_distribution<double> index_dist(0.0, 0.05 * static_cast<double>(N));
std::normal_distribution<double> index_dist(0.0, std::max(0.05 * static_cast<double>(N), 1e-12));
std::normal_distribution<double> standard_normal(0.0, 1.0);

for (std::size_t i = N_top; i < N; ++i) {
Expand Down
28 changes: 15 additions & 13 deletions localizers/easynav_simple_localizer/src/easynav_simple_localizer/AMCLLocalizer.cpp
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -239,9 +239,9 @@ AMCLLocalizer::on_initialize()
RCLCPP_INFO(node->get_logger(), "at position (%lf, %lf, %lf) std_dev [%lf, %lf]",
x_init, y_init, yaw_init, std_dev_xy, std_dev_yaw);

std::normal_distribution<double> noise_x(x_init, std_dev_xy);
std::normal_distribution<double> noise_y(y_init, std_dev_xy);
std::normal_distribution<double> noise_yaw(yaw_init, std_dev_yaw);
std::normal_distribution<double> noise_x(x_init, std::max(std_dev_xy, 1e-12));
std::normal_distribution<double> noise_y(y_init, std::max(std_dev_xy, 1e-12));
std::normal_distribution<double> noise_yaw(yaw_init, std::max(std_dev_yaw, 1e-12));

particles_.resize(num_particles);
for (auto & p : particles_) {
Expand Down Expand Up @@ -425,7 +425,7 @@ AMCLLocalizer::init_pose_callback(
yaw_stddev = std::max(yaw_stddev, min_noise_yaw_);

std::normal_distribution<double> standard_normal(0.0, 1.0);
std::normal_distribution<double> yaw_noise(0.0, yaw_stddev);
std::normal_distribution<double> yaw_noise(0.0, std::max(yaw_stddev, 1e-12));

const std::size_t N = particles_.size();
for (std::size_t i = 0; i < N; ++i) {
Expand Down Expand Up @@ -502,15 +502,17 @@ AMCLLocalizer::predict([[maybe_unused]] NavState & nav_state)
std::random_device rd;
std::mt19937 gen(rd());

for (auto & p : particles_) {
std::normal_distribution<double> noise_dx(0.0, std::abs(dx) * noise_translation_);
std::normal_distribution<double> noise_dy(0.0, std::abs(dy) * noise_translation_);
std::normal_distribution<double> noise_dz(0.0, std::abs(dz) * noise_translation_);

std::normal_distribution<double> noise_yaw(
0.0,
rot_len * noise_rotation_ + trans_len * noise_translation_to_rotation_);
std::normal_distribution<double> noise_dx(
0.0, std::max(std::abs(dx) * noise_translation_, 1e-12));
std::normal_distribution<double> noise_dy(
0.0, std::max(std::abs(dy) * noise_translation_, 1e-12));
std::normal_distribution<double> noise_dz(
0.0, std::max(std::abs(dz) * noise_translation_, 1e-12));
std::normal_distribution<double> noise_yaw(
0.0,
std::max(rot_len * noise_rotation_ + trans_len * noise_translation_to_rotation_, 1e-12));

for (auto & p : particles_) {
tf2::Vector3 noisy_translation(
dx + noise_dx(gen),
dy + noise_dy(gen),
Expand Down Expand Up @@ -636,7 +638,7 @@ AMCLLocalizer::reseed()
double yaw_variance = computeYawVariance(particles_, 0, N_top);
double yaw_stddev = std::sqrt(yaw_variance);
std::normal_distribution<double> yaw_noise(0.0, std::max(yaw_stddev, min_noise_yaw_));
std::normal_distribution<double> index_dist(0.0, 0.05 * static_cast<double>(N));
std::normal_distribution<double> index_dist(0.0, std::max(0.05 * static_cast<double>(N), 1e-12));
std::normal_distribution<double> standard_normal(0.0, 1.0);

for (std::size_t i = N_top; i < N; ++i) {
Expand Down