A Neat Package

The Deployable Structures Laboratory was founded by Dr Sergio Pellegrino in 1990 to develop new, generic solutions and to better understand the behaviour of existing deployable structures. Some general results that have been obtained include folding conditions for two-dimensional and three-dimensional structures with "scissors" joints and packaging conditions for thin membranes. Recent advances in the computational modelling of multi-body systems have led to more accurate simulations of the folding and unfolding process. The research group is active in many new fields, including Smart and Adaptive Structures, the use of piezoelectric and shape-memory alloy materials in structural actuators, and the design of special, geometrically bi-stable structures using composite materials. They have strong industrial links, particularly with the Aerospace Industry and the European Space Agency.

MPEG videos:

	Dynamic deployment of 1 metre diameter prototype of Collapsible Rib-Tensioned Surface Reflector, developed by the European Space Agency. The strain energy stored in the elastic ribs of the reflector is released during deployment.
	Launch and in-orbit deployment of Inflatable Antenna Experiment (Courtesy of NASA).
	3.5 metre diameter prototype of cable-stiffened pantographic reflector. Deployment is driven by two motor-controlled cables running on smooth pulleys. The same two cables apply a state of pre-stress onto the fully-deployed structure, ensuring uniform pretension of all cables. A stiff cable network provides a series of accurately located support points for the reflective surface (not included in this model).
	New concept for a deployable solid-surface antenna. The surface is divided into panels connected by single-degree-of-freedom hinges (revolute joints) forming six wings that are connected by coupling rods. Deployment is driven by six electric motors.
	Inflation of an Aluminium tube that has been pre-folded according to a triangulated pattern. By choosing special dimensions for the triangles, the tube can be folded and deployed without deforming the triangles.
	Aluminised mylar folded in complex, computer-generated patterns is the key to this deployable structure designed for use in space. Expansion and contraction of the aluminium-alloy frame is controlled by a cable powered by an electric motor.