For industrial product design, it is very important to take into account
assembly/disassembly and maintenance operations during the conceptual and
prototype design stage. For these operations or other similar operations in a
constrained environment, trajectory planning is always a critical and difficult
issue for evaluating the design or for the users' convenience. In this paper, a
customer-oriented approach is proposed to partially solve ergonomic issues
encountered during the design stage of a constrained environment. A single
objective optimization based method is taken from the literature to generate
the trajectory in a constrained environment automatically. A motion capture
based method assists to guide the trajectory planning interactively if a local
minimum is encountered within the single objective optimization. At last, a
multi-objective evaluation method is proposed to evaluate the operations
generated by the algorith
