TOM the Climbing Robot. based on the 1895 Lehmann Toy

[robothut]

I always liked string climbing toys and earliest version that I can find that was mass produced was by the Lehmann toy company back in 1895. It was called TOM the Climbing Monkey. This toy has been copied by every major maker of tin and plastic toys since then, but non of them were robot themed. So here is TOM the climbing Robot that you can 3d print and build. I also did a simple Rocket and UFO design that is much easier to build if you like. This video is both a demo video and a build instruction video.  The Rocket and UFO bodies as well as the string pull rings were Remixed from other builders. Here is the info on that.

 The rocket body is a remix of a 3d print by gCreate and the link to the thing-I-verse files is here. 
https://www.thingiverse.com/thing:427789
The UFO body is a remix of the UFO by daikokuten and the thing files are here.
https://www.thingiverse.com/thing:3785391
This video covers the build and printing info for these projects.
 The pull rigs that you tie to the ends of the strings, they are from  "Greg Zumwalt" here is a link to his string climbing mech.
https://www.youmagine.com/designs/string-climbing-mechanism

 

[robothut]

A few pictures of the prototypes and the final versions of the climbing toys. The yellow robot, purple/blue rocket and the dark gun metal UFO were the prototypes.

The arms and legs of the robot move as it climbs and even the gears on the side turn.

I tried different strings from very thin nylon to thick hemp bead string. What worked the best was a red thread the wife gave she called darning thread. If the line or thread is to small in die. the it can get stuck in places that it does not belong , like not on the pully but the shaft. If the string is to thick like the Hemp Bead string then it limits the number of turns you can put on the small pullies. I wanted to try Kite string and Yoyo string but could not find any in my area.

 

[robothut]

Pic's.

[robothut]

Some of the different strings I tried.

[robothut]

To start the build you would glue the two pully parts together and get them to turn freely in the mech. box unit.

[robothut]

Mech. box and pully STL files.

scrMechanicalFrame.stl scrPullyAxle.stl

[kennetzel]

Way cool.

[robothut]

Next you can install the string you plan to use. If its thin enough you can use 60 to 70 inches long piece, that would be as far as I can spread my hands / fingers apart. You need to divide the tread into thirds, as you hold the two ends of the tread just loop it with a finger on the left hand and then with the right hand and pull as you still hold the ends. you now have 3 sections of the same length. Tie a marker knot at one of the thirds. What this means is if you had a string that was 60 inches long, you want a knot tied 20 inches in on one end.

The pully axle unit you glued together has a large pully and a small pully. The large pully has a hole that leads down to the small pully. Feed the 20 inch length of string end into this hole. When it comes out the hole in the small pully pull the string until the knot is down in the pully hole. You may glue it if you like. I find the string stays in place even if you do not glue it as there will always be string wrapped around one pully or the other.

Now wrap the long end of the string , in this example that would be the 40 inch section, around the large pully. I wrap towards me so that would be counter clockwise, but the direction is not important as long in the end the string wraps the opposite direction on the small pully.

This picture is of the mechanics for the Rocket or space ship but it is the same as the climbing robot except the climbing robot will have longer axles for the cams and gears.

[RoboDerby]

(Comment moved to end of John’s build explanation. Please delete entry Brian. Thanks.)

[robothut]

Next fit the pully unit in to the mech. frame. This way you can pull the string back and forth until things move freely. If you need to use sand paper to make the pully axle parts turn freely.

[robothut]

Now if you are building the Rocket or the UFO then you just place this Mech. unit inside the two space ship parts, glue it together and add the string pull Rings and your done.

But we are building the climbing robot. So there are a few more steps. We need to push on the two CAMs on to the pully axles as far as they can go. Both cams should have the same orientation.

[robothut]

Here is the STL file for the CAM's.

scrCAM.stl

[robothut]

Now the arms and legs move do to the rotation of the cams. And to change the rotation to back and forth movement we use 2 closed levers on each side. They have to stack so they have different height spacers built in. I like to use the short spacer ones for the legs and the high for the arms. These linkage parts have Hex shafts that go threw holes in the Main Body and Body side parts the arms and legs will get glues to these Hex shafts as shown.

[robothut]

STL file for the Arm and Leg linkage parts.

scrArmAndLegLinkage.stl

[robothut]

The Lower arm and the Upper Leg parts are what get glued to the Hex shafts of the linkage. The Hex shafts should make it easy to put these parts in the position if you look at the video or the pictures. Here are the Lower Arm and Upper Leg files. These parts must be printed with supports.

scrArmLower.stl scrLegUpper.stl