PROTOTYPE OF THE FIRST ROPE PISTON

August 02013

However, due to its wide cross-sectional area, its rated Pounds per Square inch rating resides at 3.17, Rise™ Robotics's current means of measuring its ultimate performance. Its application demonstration was to assist Hesham's lift project an affiliate of Rise™ Robotics. As with any new innovation, failure modes are not entirely understood. This design would fail imminently if the lines were ever tangled by improper handling. 

Blake Sessions discovered a way of compacting and balancing the ancient Chinese Windlass mechanism as a cost effective way of efficiently converting rotary motion to linear motion. This compacted windlass approach is known as the "conical differential drive".

As a proof of concept, a 31 inch actuator was made utilizing a 1mm steel cable that could pull 45lbs over 100mm in an astounding 1.8 seconds. While weighing 300 grams.

Operating load
Cyclone reduction
stroke
stroke time (sec)
Speed
Mtbf - “life”
failure modes
weight

45 lbs
14
105.5 mm
1.8 sec
59 mm/s
10
immediate entanglement
0.7 lbs
 

70 %
1.8 inches
7.00 inches
31.6 inches
15.1 %
3.17
Pull Only

efficiency
height
width
length
contraction ratio
psi
push/pull