Gears robot

SRI international: Abacus drive
https://patents.google.com/patent/US20190242464A1/en?inventor=Alexander+KERNBAUM An apparatus includes a first ring having an open annular space and a variable-width groove disposed on an interior peripheral surface of the first ring; a second ring rotatable within the open annular space of the first ring, where the second ring has a respective variable-width groove disposed on an exterior peripheral surface of the second ring; and a plurality of rollers disposed between, and configured to roll on, the interior peripheral surface of the first ring and the exterior peripheral surface of the second ring and rotatable therebetween.

https://patents.google.com/patent/WO2019221703A1/en?q=pure&q=roling&q=cycloid+%2c&q=sri&oq=pure+roling+cycloid+%2c+sri filed by SRI international A variety of mechanisms are provided for coupling the rotation of shafts or other mechanical elements having parallel but offset axes of rotation. The coupling mechanisms can couple such input and output elements via pins that are in contact with the input and output elements. The pins, upon rotation of the input and output elements, can engage in substantially pure roiling motion with respect to respective contact surfaces on the input and output members. Accordingly, the pins can reduce the number of bearings and increase efficiency relative to alternative coupling mechanisms. Such couplings may be employed in a variety of applications, including the coupling of rotations between elements of a cycloidal drive or a transmission that includes a member that undergoes cycloidal motion. For example, this coupling could replace the cage gear of a cycloidal drive in coupling the output to the cycloidal disc of a cycloidal drive. Invented by inventor:(Alexander KERNBAUM)

https://www.youtube.com/watch?v=zoaHeamUqBE Robotics engineers at SRI International in Silicon Valley have developed the first new rotary transmission design since the invention of the Harmonic Drive gear. Learn more: https://spectrum.ieee.org/automaton/robotics/robotics-hardware/sri-demonstrates-abacus-rotary-transmission. Zero backlash high gear ratio. From Tracked_vehicle SRI’s Abacus drive has beads that roll in and out of a groove with a variable diameter. This causes the beads to effectively change their diameters depending on where in the groove they are, resulting in the same kind of cycloidal motion that you see in Harmonic Drive gears, but with less backlash(zero) than a harmonic drive and much less complex manufacturing.

Cycloidal

 * http://www.harmonicdrive.net/ See Cnc buildlog
 * https://www.nabtescomotioncontrol.com/products/ Cycloidal Gearbox, Nabtesco

Wheels

 * Tracked vehicle make steel wheel with outer used car tire.
 * http://www.superdroidrobots.com/shop/item.aspx/robot-drive-wheel-10-inch-pneumatic/1516/
 * http://www.robotmarketplace.com/products/wheels_main.html  Wheels
 * http://clients.wm.co.za/clientproofs/trojanTrolleys2/rubber.html
 * http://www.seajaycastors.co.za/products.htm Pneumatic wheels
 * http://caslad.co.za/nwheels.htm Pneumatic wheels 200,300,400mm  R200, R380
 * http://www.electricscooterparts.com/headsetbearings.html

diy

 * http://www.diy-review.com/scuPDHowToHENfs0/Plastic-ball-bearings.html plastic ball bearing
 * http://www.cryogenius.com/cnc/bearing/ DIY, make own thrust bearing and matching cryog shaft collar. Thrust bearings are mounted on the inside of x-axis platform, removing strain from the outer bearings.
 * http://www.wolfgangengineering.com/

worm gears
https://www.youtube.com/watch?v=AYkX1dA3LFM squaring off a one cm disk, it is orthogonally aligned against a back plate that mounts flush between the chuck jaws. 13min. by max runout

Drilling small holes
https://www.mscdirect.com/product/details/41868324 Accupro - 1/2 Inch Shank Diameter Straight Shank Micro Drill Chuck Adapter and Chuck 1/64 to 5/32 Inch Drill Chuck Capacity from micro drilling small holes without breaking the drill bit by Joe Pieczynski

Max runout channel
https://www.youtube.com/watch?v=Jkk-9T1m6tM part.5 on making gears in workshop. n part 5 of our series on automating the gear making process, we build a device to measure the gears we have made so far, improve the process and make some new gears. Shows mechanism for testing depth of gear teeth.

https://www.youtube.com/watch?v=35rbL06fcHQ plastic shredder.

Drill center hole
https://www.youtube.com/watch?v=Y9UWzaaa8lw I am going to try to lift substantially more weight with a wiper motor than the last try with a belt drive.

CMTO
The Concentric Maxi Torque keyless hub-to-shaft connection system. http://cmtco.com/concentric-maxi-torque  ,, http://cmt.shotgunflat6.com/images/uploads/cmtspreadblue2crop.png Engineers at Custom Machine and Tool Co., Inc. found that fasteners used to connect components to high speed shafts had to have lower intertia and create fewer vibrations. We also knew that component alignment, accuracy, holding ability and runout became critical at higher speeds. When no other company could offer a compact bushing for shafts less than an inch in diameter, CMT was up to the task. We decided to design, build and patent one.

Tracked platform
http://www.tradekorea.com/product/detail/P348518/rubber-track-undercarriage-with-slew-bearing.html Pivot platform uses slew bearing.

Knife edge bearings
http://www.thingiverse.com/thing:343922/#files

shaft coupling
https://www.youtube.com/watch?v=GDALEaHXt1g Key shaft to spline shaft coupling method. Connecting a motor to a gearbox in a precise manner with an alignment plug. Linked from CncControllers, http://opensourceecology.org/wiki/Power_Cube_VII

suppliers
Tubing, chromed rods
 * https://www.roodepoortmetals.com/ tubing
 * http://www.tubecon.co.za/, http://www.macsteel.co.za/products/stainless-steel
 * http://anvilchrome.co.za/products-specs/ induction hardened chrome.
 * http://bronscorcc.co.za/castings.html castings of wheels.
 * http://www.sdp-si.com/
 * http://www.beltingonline.com
 * http://www.robotmarketplace.com/products/gears_main_miter.html Bevel gears
 * http://www.verbolt.co.za M2, M2.5 2mm, 2.5mm threaded rods

https://sdp-si.com/ Gears, pulleys

http://www.servocity.com/html/worm_gearbox.html#.VCHC3hYrEZQ Worm gearbox Tamiya

http://www.servocity.com/html/pan_tilt_roll___accessories.html pan/tilt platform 20kg

“ServoBlocks”, n.d. http://www.servocity.com/html/servoblocks.html.

“Slip Ring 6x2A (6 Wires, 2 Amps) 4A Available | eBay”, n.d. http://www.ebay.co.uk/itm/Slip-Ring-6x2A-6-wires-2-amps-4A-available-/270744485832?pt=LH_DefaultDomain_0&hash=item3f09a0ffc8&clk_rvr_id=307665187420&clk_rvr_id=308031459860&clk_rvr_id=318533295051.

http://www.rapidonline.com/Electrical-Power/Toothed-timing-pulleys-and-belts-71294 “Toothed Timing Pulleys and Belts”, n.d.

http://www.rapidonline.com/electrical-power/6mm-diameter-worm-gears-length-10mm-pack-of-50-37-0305 $1.50 pack of 50 and bevel $1.7 for one.

http://www.rapidonline.com/electrical-power/steel-shafts-pack-of-50-2mm-dia-x75mm-37-0350 Steel shaft pack of 50 2mm diameter for worm gear $1.2

http://www.econobelt.com/

http://www.khkgears.co.jp/world/RCandROBO.html

http://prosafesecurity.co.za/catalog/58  Bevel gears for gates

Gear hobbing
See Machine design. Links on making exact worm gear and matching worm wheel for telescope star tracking. Download zipped files on taper, pitch calculations for gear hobbing. http://www.amazon.ca/Gears-Gear-Cutting-Ivan-Law/dp/0852429118/ref=pd_sim_b_6
 * http://www.mitcalc.com/doc/gear4/help/en/gear4.htm

Chris Heapy

 * http://www.dragonworks.info/Metalworking/Gearmaking/Gear%20Making.htm links to http://web.archive.org/web/20040215142957/http://easyweb.easynet.co.uk/~chrish/worms.htm
 * http://web.archive.org/web/20040202172643/http://easyweb.easynet.co.uk/~chrish/eqnotes.htm#wga telescope positioning
 * http://web.archive.org/web/20040210141311/http://easyweb.easynet.co.uk/~chrish/ Various lathe, milling techniques.

Claudio Grassi

 * https://www.youtube.com/watch?v=lqreWsmXG4k Lathe to mill turn table conversion. Indexing the chuck for gear broaching. This type of repetitive motion is automated with CncControllers.
 * https://www.youtube.com/watch?v=BgGXQUeYNKw Broaching small internal gears for use on model truck.
 * https://www.youtube.com/watch?v=ie7dNOLgno0#t=3.765396 cutting worm wheel with tap.

Myfordboy

 * https://www.youtube.com/watch?v=-umcQtrn1CQ worm and worm wheel free hobbing method.
 * http://www.astronomyasylum.com/gears.html Hobbing large strip of aluminium cheaply for worm wheel. Telescope, astronomy. Large Aluminum Worm Gears Fabricated From Aluminum Strips
 * https://www.youtube.com/watch?v=7zMgJXMHcNs Sells plans for making own involute gear cutter by myfordboy

Planetary gear

 * https://www.youtube.com/watch?v=4HPtIXlno3w setup fixed for platform rotation.
 * https://grabcad.com/library/micro-planetary-gearbox-1 Micro gearbox 1:5 ratio
 * https://www.thingiverse.com/thing:2550882 high ratio gearbox 400kg power. https://www.youtube.com/watch?time_continue=8&v=pmw5CzfBBiU
 * https://www.thingiverse.com/thing:2054378 50:1 planet

Mrpete222
https://www.youtube.com/watch?v=GSBEtPjAX28 grinding a tool bit.
 * http://www.mrpete222.com/ Official site.

Hour glass
http://www.kinematicsmfg.com/quality/hourglass-technology/ (Scan design with laser scanner and reproduce 3d printer) Kinematics’ patented hourglass design is unique because it can withstand a survivability load that is four to nine times greater than loads carried by typical slewing drives. The special hourglass shape of the drive allows more teeth to be engaged at one time, enabling much higher torque endurance. Our technology delivers a stronger and more durable drive so your equipment can perform longer and more reliably.

plastic ball bearing
http://www.youtube.com/watch?v=0sfNEHDPucs xiros Free from maintenance and lubricants, suitable for extreme environments

Xiros plastic ball bearings from igus are designed for applications where the use of grease or lubricants is prohibited. The food and drinks industry, in particular, bans the use of such substances altogether. The design of igus xiros ball bearings is the same as conventional steel bearings, consisting of an inner and outer race, a cage and a number of balls; the only difference being that the races and cage are made from igus tribological polymer materials. These plastic materials are self-lubricating and thus negate the need for lubricants. http://vimeo.com/63738557

http://www.igus.co.za/wpck/default.aspx?Pagename=ballbearing&C=IL&L=en

http://www.youtube.com/watch?v=ub-3kjljf-o 3d printing ball bearings 0

http://www.youtube.com/watch?v=GJtRKDhfnqo  printing gears 1

http://www.youtube.com/watch?v=ehnzfGP6sq4 printing house

Worm gear
http://www.thingiverse.com/thing:8821 Description

Ok, once you have an involute gear library AND a trapezoid thread library, you can easily make the simplest of worm drives, i.e. the non-throated kind.

Like all worm drives, the gear advances by one tooth for each revolution of the screw but with non-throated ones, there is only a single point of contact at any one time, and so torque and wear capabilities are limited.

UPDATE: As I pointed out in the comments, AFAIK a trapezoidal profile for the worm screw is all you need to match the worm gear's involute.

To make them mesh, all I did was to make sure that: 1. the pitch is the same (distance from crest to crest), 2. the pressure angle of the gear is equal to the angle of the sides of the screw profile, 3. the distance between screw and gear is equal to the gear's radial pitch plus the screw's mid-profile radius, and 4. the twist on the gear is equal to the gear's pitch radius divided by the screw's mid profile radius, with a sign depending on the screw's handedness.

Many methods have been used for control of backlash in geartrains. George W. Michalec's book Precision Gearing: Theory and Practice, published in 1966, has a good description of many different methods. Most have disadvantages such as increased size, weight, and cost. Examples are split, spring-loaded scissor gears and the use of auxiliary geartrains. from https://www.google.ch/patents/US6285339

ball screw
moved to Machine design

Bearing numbering

 * Pillow block bearings: UCP201(12MM ),  UCP202(15MM ) ,  UCP203(17MM ),, UCP204(20MM ),,UCP205(25MM )
 * https://www.astbearings.com provides online numbering
 * https://www.astbearings.com/catalog.html?page=product&id=6201-2RS 6201rs  12mm id,  https://www.astbearings.com/catalog.html?page=product&id=51101  12mm thrust bear
 * https://www.youtube.com/watch?v=WLx3ov6jvik
 * http://www.engineerstudent.co.uk/bearing_numbers_explained.html

674ZZ Shielded Ball Bearings 4mm x 7mm x 2.5mm 10 Ball Bearings 674ZZ Shielded Ball Bearings, the inner diameter is 4mm, outer diameter is 7mm and the width is 2.5mm, Bearings are made of Chrome Steel.

This 608ZZ shielded 8x22x7 miniature ball bearing is a single-row bearing for supporting radial loads. (inner x outer x width)


 * MR105-ZZ, 5x10x4 mm, Radial Bearing


 * 605zz 5x14x5
 * http://www.aliexpress.com/store/product/MF52ZZ-2x5x2-5-Shielded-Miniature-Ball-Bearings-with-Flange-100-pieces/814838_733368892.html?_escaped_fragment_=#! Bearing numbering system from 3mm to 15 ID.
 * http://www.cnczone.com/forums/diy-cnc-router-table-machines/13924-bearings-608-2rs-vs-608-zz.html Links to five threads on bearings to use for cnc.   ZZ means it has a metal shield on both sides, 2RS means it has rubber seals on both sides. The rubber seals will keep more crud out of the bearings. There may be some bearings or manufacturers to stay away from, but I am not aware of any. The tolerance differences between the various ABEC ratings are so small(>.0005") that it doesn't matter what the ABEC rating is.
 * 624rs 4ID x 13OD x 5thick
 * 16mm ID, 35mm OD

links
https://www.robotics.org.za/bearing-flanged-f623zz-pack-of-10.html  flange bearings f623zz
 * Machine design