Position and connect blocks. Place Joint and Body blocks in proper relative position in the model window and connect them in the proper order. The essential result of this step is creation of a valid tree block diagram made of
Machine Env — Ground — Joint — Body — Joint — Body — ... — Body
with an open or closed topology and where at least one of the bodies is a Ground block. Connect exactly one environment block to a Ground.
A Body can have more than two Joints attached, marking a branching of the sequence. But Joints must be attached to two and only two Bodies.