Sunday, December 23, 2018

Robot Arcade -

I am creating a "Robot Arcade" on as a holiday project!  You can visit the site LIVE here:

Robot Arcade -
It is a work in progress, but works well to get all of the robot fantasy out of your head.  I am building this "robot" with mostly parts from recycled printers and some 3D printed parts.  It is using an L298N as the motor controller.  All driven by a Raspberry Pi that is streaming video and controls between it and the servers. I will be using MQTT to pipe commands from the server to various computers controlling the scene.

In the first boot strap days, it was 'challenged' by the 'internet' robot operators.  my motors were not secured and were dancing around the scene.  Actually somewhat fun.  Today I put together this motor mount design and will be using it to build out the Arcade.

3D CAD designed to be a motor mount

I don't quite know what I will do with this yet, but I would like it to be some form of a remote robot - 'game of skill'.  it is fun to see some form of a battle or skill challenge performed by the remote operators.

I am open to suggestions for game ideas!  :)

Monday, December 17, 2018

Centi (#1) - A Bio-Inspired Centipede Robot


I have always wanted to build a Centipede type robot.  It would combine a walking and turning mechanism. And be able to scurry around through obstacles and dreams. Now that I am a self-styled robotist with a 3D printer, I can build one!


Basically, the robot needs to support its weight and payload, be able to move forward/backward, and then steer to the left/right. The target motive force is a single/duo of dc brushed motors, with connectors between the 'segments'. It needs to carry a camera, lights, speakers, for streaming. It needs controller, wifi, RPI(?), and battery / portable power. 

Right now, I am satisfied with it "scurrying" about. But, getting those legs tangled in vertical things will be a future problem. I am not going to worry about that in the first prototypes.

The key to this design will be how to create the basic rotational motion of the leg to Lift-Place-Move each of the legs.  First thoughts had a pair of rotational gears, one to lift the legs, the other to move forward-backward.

Initial thoughts for Leg Motion, placement, and mechanisms
I created a couple of drafts on the cam/lifter/crankshaft thoughts.  But, this seems to be overly complex.  It needed simplicity.

Ball and Socket

The simplest thought would be to have a gear/cam spinning and moving a lever arm of the leg, that is suspended by a ball and socket arrangement. The most immediate concern would be the amount of friction in the ball/socket. This could be managed with some grease. future designs could even use metal or teflon to reduce the friction.  To the CAD!

First draft of the ball/socket - OpenSCAD
The plan is to 3D print a single full leg segment for testing and Prototyping. I am using a 'chopstick' for the leg.

First print for the prototype - Test, Adjust, and Print again!
The first rough print yielded some immediate feedback. The socket will need to be wider to better contain the ball.  but, sizing on ball for a chopstick style let was right.  I was playing wth an old cam print for sizing, this will go next into the design.  I am also thinking that having a modular/adjustable leg segment will be important.  But, I do not want to get too far ahead in the design there are still a lot of moving variables.

Internet inspiration:
Festo BioFinWave

here are some companies doing somethings with various linkages, but provide a 'fin' that can move on fluid surfaces:

It will be along way for me to go, compared to these systems.