Most teams have used Poly-Cord type material to make their roller systems this year. FRC Team 1711 used Thera-Band. A physical therapy medical based product. Resistance values are color coded.
Yellow=1.8 lbs. (LIGHT)
Red=2.7 lbs. (MEDIUM)
Green=3.1 lbs. (HEAVY)
Blue=4.5 lbs. (EXTRA HEAVY)
Black=4.9 lbs. (SPECIAL HEAVY)
Silver=8.6 lbs. (SUPER HEAVY)
I’m really interested in how well this works, do you have any videos?
system
March 6, 2012, 12:32am
3
Nice! How effective did you find it was?
Do you think there are any advantages over polycord?
How did you splice the ends?
I believe they come as a closed loop band. Someone correct me if I’m wrong.
We used Thera-Band as a prototype shooter wheel material in 2009. It worked awesomely.
Nice idea using it as an intake belt!
-Brando
That particular one was connected using rubber cement. I explicitly asked the team that question.
I only recall seeing them out on the field once, but it was moving a ball at the time, so feel free to draw a conclusion from that data point.
What exactly do those weights measure? If I were to apply the rated force to pull the band how far would it stretch?
Resistive force (albeit in mass units!) at a certain percent elongation:
http://www.thera-band.com/UserFiles/PullForceChartUpdate_500pxW.jpg ](http://www.thera-band.com/faqs_consumer.php#faq_1 )
EDIT: more data is available in the Thera-Band Instruction Manual . The OP’s table corresponds to approximately 50% elongation.
Well right from the get go it has the advantage of not needing a 2 inch diameter pulley to work.
Just thought I would comment because this looks like it could help people with their frisbee intake ideas! I will show this to my team and see what they think!