struct mola::state_estimation_smoother::StateEstimationSmoother::GtsamImpl::GaugeAnchor

Overview

A strong prior pinning a gauge freedom: a direction of the state that no measurement observes yet, e.g. where {map} is before any source gives poses in it. A weak prior would leave the system nearly singular, which some GTSAM versions reject during Cholesky elimination. Anchors are only placed on variables that are never marginalized, so they can always be withdrawn once measurements start observing that direction.

struct GaugeAnchor
{
    // fields

    std::optional<size_t> pendingIndex;
    std::optional<gtsam::FactorIndex> isamIndex;
};

Fields

std::optional<size_t> pendingIndex

Position in newFactors.

std::optional<gtsam::FactorIndex> isamIndex

Once inside the smoother.