Abstract: A method of designing a reflector array for high integrity localization is disclosed. The method includes: defining a boundary of one or more localization regions; determining a number and location of unique reflector arrays; establishing a set of candidate reflector arrays; determining a subset of detectable reflector arrays of the candidate reflector arrays; verifying detectability over time of the subset of detectable reflector arrays; determining the subset of detectable reflector arrays that are robustly unique under sensor errors and/or reflector perturbations; and determining whether a sufficient number of detectable and unique reflector arrays have been established.

Abstract: According to the present invention, there is provided a filler compound, the filler compound comprising filler particles and a binder, wherein the filler particles comprise particles of at least one glassy material, and the particles of glassy material are at least 10 wt. % of the dry mass of the filler compound, and wherein at least 30 wt. % of the filler particles have a diameter between 50 and 100 microns inclusive. Use of a filler compound in the erection of a structure is also described.

Abstract: A facemask assembly includes a facemask including a face seal defining a first end and a second end, the first end at least partially defining a filter cavity, the second end configured to form a seal with a user's face; a filter cover coupled to the first end, the filter cover further defining the filter cavity; and a filter assembly positioned within the filter cavity; and a restraint coupled to the facemask, the restraint configured to secure the facemask to the user's face.