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were grouped into eight distinct techniques. Use of these techniques across tasks of different geometry, ramp angles, radii and drape path was identified using video analysis techniques from the ergonomics field. This revealed strong links between specific features and techniques, revealing a systematic approach to layup. This has enabled the first step toward producing a design for manufacture knowledge base surrounding hand layup. This could then be used to inform the development of the layup process, improve training methods and assist in the design of future automated solutions.

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The rotational spectra of six isotopomers of trimethylamine-alane have been observed by pulsed beam Fourier transform microwave spectroscopy. Hyperfine analyses of the symmetric top isotopomers, (CH&NAlH3, (CH3)3NAlD3, and (CH3)3l5NA1H3, determined the spectroscopic constants, BO, DJ, DJK, eQq(27A1), and eQq(14N). For (CH3)3NAlH3, BO = 2745.113(1) MHz, DJ = 643(24) Hz, DJK = 1372(250) Hz, eQq(27A1) = 25.032(6) MHz, and eQq(14N) = -3.777(5) MHz. Spectral assignments have also been made for the asymmetric top isotopomers, [(CH3)2l3CH3]NAlH3, (CH3)3NAlH2D, and (CH3)3NAlHD2. Substitution structural parameters of rNc = 1.487(2) and 6°C = 109.9(2)' are obtained from the microwave moments of inertia. With the assumption of rAlN = 2.063(7) A from an electron diffraction structure reported previously (Almenningen, A.; Gundersen, G.; Haugen, T.; Haaland, A. Acta Chem. Scand. 1972, 26, 3928) microwave substitution coordinates for the aluminum hydrogens give THAI = 1.585(2) A and OHAN = 98.1(6)'. The structure of (CH&NAlH3 is compared to the related complexes, H3A1NH3, H3NBH3, and (CH&NBH3. In the same series, bond orders calculated from measured values of eQq(27A1) and eQq("B) are compared to A1-N and B-N dative bond dissociation energies.

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