138g supports a joint bracket 146a 146c 146e 146g through which an axle 147a 147c 147e 147g passes upon which axle a right secondary arm 148a 148c 148e 148g pivots off center a tie bar 150a 150c 150e 150g pivots multi dimensionally upon a ball screw 151a 151c 151e 151g attached on one end to the support beam 144a 144c 144e 144g respectively and pivots multi dimensionally upon a second ball screw 152a 152c 152e 152g attached at the other end of the tie bar to an end of the secondary arm 148a 148c 148e 148g respectively according to one embodiment of the present invention rotating means 153 rotates the gear 134a in a preferred embodiment rotating means 153 is a motor which is remotely controlled to rotate a drive shaft 154 wherein the drive shaft is mounted directly to the axle 135g thereby to rotate the axle and the gear 134g since the right gears 134a g operatively cooperate together such that rotation of a first gear in a first direction will cause rotation of a second adjoining gear in an opposing second direction those skilled in the art will appreciate the fact that rotating means 153 and the accompanying drive shaft 154 may be directly mounted to other axles 135a f in other preferred embodiments referring to fig2 the right front jointed leg generally indicated at 200 embodying features of the present invention has been illustrated in an exploded side view the gear 134a is rotatably mounted through an orifice 201 to the frame 102 about the axle 135a a preferred embodiment of the gear 134a is a plastic material a preferred embodiment of the axle 135a is a threaded bolt 202 affixed with a nut 204 a nylon bushing 206 provides spacing between the frame 102 and.