Wire Bots

Massmind Wirebot presentation

Treadmill motors are available for /nothing/ by taking apart old discarded treadmills. They are commonly available at ewaste and dumps. Even in working condition they are commonly available for next to nothing. They will run on DC power and produce good torque at 40 volts, and can be controlled with great precision with about $40 worth of open source electronics.

Motor shaft connects to winch drum, and you need 3 of those so total cost in mid hundreds is VERY doable excluding labor, land, and whatever payload. Poles are about $90 for 42' ^ plus guys and cable. Assuming it doesn't need to lift a ton.

Applications:

For 3D printing large structures, like homes, or storage spaces, or clear topped growing spaces, a cement or adobe extruder is placed at the load point and material is pumped in from a mixer to the side. Typically, 3D house printers do NOT print the structural elements; they print forms, which are then filled with rebar and concrete (cement / aggregate mix). This avoids the need for special permitting, as concrete structures are known and commonly permitted. It might be possible to permit adobe or other compression type structures. The lite weight and transportability of poles, cables, and winches promotes a service where the printer is moved from location to location. The low cost promotes just leaving the printer in place as a gardening or other automation system after the structure is finished.

For Gardening, the 1st application is just mounting a web cam and taking up-close, high resolution, pictures at the same time every day. Then you stitch those together to form a detailed record. If a plant dies, you can "go back in time" and see what symptoms it exhibited. Then look for that symptom in other plants. This annotated data is ideal for machine learning. When the wirebot is all the way up, the webcam can be used for pest detection and deterrent. e.g. see and chase rabbits and moles out of the garden. Then add a set of probes and measure soil moisture, and a thin plastic tube to provide each plant with the ideal amount of water. And use the probes to destroy weeds you identify from the photo at the comfort of your office desk. you can even crowd source your weeding. Eventually, add a seed dispenser and you have a much larger farmbot for less made from junk.

See also:

• https://hackaday.io/project/181891-oboom-low-cost-deployable-linear-actuator Very interesting linear actuator using three measuring tapes and spacers.+
• https://hackaday.com/2021/01/26/cable-mechanism-maths-designing-against-the-capstan-equation/ The Capstan Equation tells us that, for a given holding tension on one side, the maximum amount of tension we can put on the other side of the cable without slipping is given by: T_L = T_H2^µ_sθ where:
  • µ_s is the cable’s coefficient of static friction
  • θ is the total bend angle between your two tension vectors
  • T_L and T_H are the magnitudes of each respective tension value.
  +
• https://youtu.be/NHCXvCGlw-0 3D printing in a large format.+
• https://www.youtube.com/playlist?list=PLuCEOfGDb3iQ7TfJ4aqXMaJIMknvGkxDV A playlist of parallel cable robots. These use multiple reels for each attachment point to control orientation.+
• https://www.youtube.com/watch?v=7HNAL8ZKdyM A /very/ fast cable robot.+
• https://www.youtube.com/watch?v=9BN3TZJDsms A cable robot with a sprung center rod, and cables down from the top only.+
• https://www.youtube.com/watch?v=9KMptw7ZgVI A wearhouse sized, human lifting, motion simulation wire bot.
• https://www.youtube.com/watch?v=APytl7GxOUQ Using math to setup arbitrary control systems for unusual mechanisms.+
• https://link.springer.com/article/10.1186/s10033-018-0267-9 a review of Cable-driven parallel robots (CDPRs)
• http://www.thingiverse.com/thing:1024307 Tensegrity Delta.
• Skydelta 3D printer:
  • https://designmakeshare.wordpress.com/2013/09/16/introducing-skydelta/
  • https://reprap.org/wiki/TriDPrinting.com_Flying_SkyDelta
  • https://github.com/brandonheller/skydelta

• https://hackaday.io/project/26938-arcus-3d-c1-cable-3d-printer Arcus-3D-C1 - Cable 3D printer
• https://hackaday.io/project/166527-cable-robot Cable robot.

Code:

Interested:

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