Artificial Muscle from Fishing Line
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- เผยแพร่เมื่อ 18 ต.ค. 2015
- A recent discovery, first reported in February 2014 in Science, is that inexpensive highstrength polymer fibres used for fishing lines and sewing threads that are twisted, coiled and heated can actively contract and expand with a similar or even much greater force than human skeleton muscles. The objective of this video was an attempt to demonstrate the performance properties of such artificial muscles made of polymer fibres.
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One of the best DIY overviews for this I've seen yet. Thanks so much!
Thank you :-)
Quite the elaborate setup you have there Barbara, good demonstration!
I'm trying to coat nylon muscles with a thin layer of conductive silicon for the heat-up. Probably here the heating is not homogeneous.
Hi wolfangouille, that would be a perfect solution, but I didn’t have access to thin-film metallic coated nylon lines and therefore chose the solution with the conductive sewing thread wrapped around the fishing lines. Best regards, Babs
This is what I call a high quality video!
Großartig ... :-)
Really nice, its a very neat description. I guess all the papers should be published this way rather than older print method
Hi. Could you tell me what is the hightest tempreture that i can apply on fishing line muscle before it broked down?
Hi Mateusz,
the highest temperature I’ve used was about 110 centigrade. The problem seems to be the contact between heating wire and fishing line - if it is too close the Nylon line can melt. Temperatures between 60 and 90 centigrade are usually unproblematic. Kind
regards, Barbara
hi, nice video. i created the muscle and it seemed to expand a little on the first heating, but after the initial heating it then worked as shown in the video. is this normal or did i just melt it a little? (used a hairdryer, 0.25mm 3.30kg fishingline)
Hi ANTIMONcom,
thank you for the flowers JIt is pretty normal that the fishing line expands when being heated up for the first
time. This is a temporary effect and usually doesn’t happen in the subsequent
heating cycles.
Kind regards, Barbara
Hi Barbara,
You have done an excellent job and have inspired me to try to reproduce your setup.
I'll need some additional information on the actuator heating element and its drive power requirements to move forward. Do you have a specific part number for the silver coated nylon so that I can get the specs and find an equivalent product.
It looks like you are driving it by turning on a power supply - how did you set it up to drive the heating element (Voltage, Current - it appears to be constant current). Did you plot the supply output?
Have you tried testing the muscle across a range of contraction rates?
Thanks and Happy New Year
Hi Phil,
thank you for the compliments J
As power supply I have used a Basetech BT-305 unit. It can provide up to 30 V and 5 A
DC. I have operated the heating usually at 20 V and 0.5 A (supply output 10 W).
The silver coated nylon threat I have used a Shieldex Conductive Sewing Thread
Size 92 (PN# 260151023534oz) with 0.2 mm diameter and a specific resistance of
50 Ohms/m. This sewing thread was superior to any other heating wire because it
can be easily wrapped around the fishing line and doesn’t melt the actuator
even at higher temperatures. The contraction takes quite long within my setup (one
to two minutes) in order to contract by about 10 %. The cooling phase takes
even longer in air. Higher contraction rates can be achieved by alternating heating
and cooling with hot and cold water (see the original paper of Carter S. Haines
et al.), but this was way too much effort for my experiments.
A Happy New
year to you too and kind regards, Barbara
So how fast can the "muscle" change shape?
Dear Michal,
the contraction speed depends on the heat transfer rate from the electric heating to the muscle. In my experiment the heating coills were loosly connected to the nylon thread and therefore the contraction rate was low (as you can see in the diagram at the end of my video). More problematic is the expansion speed, which depends on the cooling rate. Cooling down obeys an exponential law and is therefore the bottleneck of the actuation speed.
Best regards
Babs
+Barbara Trost; Hi Babs! I have a question along the lines of what Michal had asked. While the contraction speed is dependent on heat transfer, will the muscle contract at different speeds based on various temps ran through the muscle?
+Phantomofthedisco1 Hi, according to the original work of Carter Haines et al. the contraction and expansion rate depends strongly on the thermal diffusivity of the surrounding medium. The high thermal diffusivity of Helium gas, for instance, greatly improves the passive cooling. Another example is a muscle that was hydrothermally driven in their experiments by switching between cold (~25°C) and hot (95°C) water. They reached a reversal contraction of 12 % with 0.5 kg load at an actuation frequency on 1 Hz. If the thermal diffusivity cannot be affected in your experiment you can try to compensate by increasing the heating temperature but you need to take care of the melting point of the polymer fibers. Best regards, Babs
great idea
Hello! What type of fishing line is this exactly?
Dear LegoIngr,
for the experiments I have used three different types of fishing lines, which are “Tebco Topic Specialine”, “Anaconda Peacemaker”, and Anaconda Untouchable” with diameters of 0.45 mm, 0.38 mm, and 0.18 mm, respectively. The fishing lines were loaded with weights between 50 g (the 0.18 mm line) and 290 g (the 0.45 mm line). Kind regards, Barbara
Thank you very much for your response! Your video is the most informative on the topic from all present on youtube, thank you for that also! :)