Wednesday, September 5, 2012

Robot Fist & Brain Stub

Rare boxing glove creates 1st robot fist

An interesting take on robot arms is the new Red Robot Fist. The Fist needs only one degree of freedom to activate and carry through its striking potential. It serves as a test for machine output ports and as a machine security device on the latest line of Propeller Super Computing Machines.

SOURCE  The red Fist was purchased at the mystical Night Market of Red China and is a small stitched and padded boxing glove designed to manually strike the body repeatedly to impart enough force to help increase circulation. Such strikers come in all sorts of sizes, shapes and promotions. This one is very interesting, and rather rare among the cache.

MECHANISM  The boxing glove is mounted to a straight wooden arm with a ball mount at both ends. The fist has the most simple actuator using a single servo activated via one Propeller port. Activation temporary moves a catch to release the "spring" cocked fist. The fist then forcefully moves as needed. With two configuration designs, one releases the fist so that it traverses at least a 90-degree arch. The 2nd configuration launches the fist much like a rocket, in a straight line of motion like an arrow, using a launching tube and a compressor spring. This borrows (and adds) some technology from the Big Brain's Micro Space Program. However, instead of using compressed air fuel, the energy comes mechanically from the cocked mechanism and spring. The spring is either a pull spring or a compression spring found in the parts bin.

USES  The Fist is an experimental platform for testing many output ports and pins, and for acting as and testing a new security device. It's a novel approach by concept, as the boxing glove and its softness is a relatively benign system. Though relatively harmless with mild forces, a stronger spring and latch mechanism can indeed pack a wallop!

ROBOTIC BRAINS  Robot brains with arms, fists, fingers, and internal transforming and signaling agents, both electronic and mechanical, are relatively new concepts being explored.

SERVO & PROGRAMMING The servo is a standard Parallax servo with the activating program code taken from the Parallax OBEX. Propeller programming is in SPIN.

PORTING  The device is easily ported from one machine to another and two such devices can make a nice set of arms with a single minded purpose of security.

ORIGINS  The Red FIST has its basis and idea from the Big Brain Stub, designed July 7th, 2011 and as presented here from the original post. seen below..

Designing a Big Robotic Brain Stub
(from July 7th, 2011)
Discovery post

The study and design of Brain Stubs is progressing. The project will also require, in addition to technical merit, some art and imagination. Unfortunately there were no suggestions for the shape of a Brain Stub so the project is progressing slowly. Apparently the right side of the gray matter is mute.

The Investigation

The investigation begins with weight and mass. Since the stub will be servo driven with props, it must not have too much mass. Although Wonder-Board is extremely light weight, it still has mass under consideration and appreciable weight in large sizes at various extended positions.

Determining Mass and weight

Both are determined by shape, and shape must adhere to the requirements set in the previous Brain Stub post. For mass, the formula F = (M)(A) is utilized. The servo has ramping and can therefore control inertia.


Control will be under the Brain Stem as previously planned. This allows many functions of programming for the servo(s).


Now under consideration are two degrees of freedom but it is not known where these will locate. Enough parts exist to do 2 DOF and this is in compliance with the Brain Stem. The board can immediately handle 2 servos.

Brain Stub Design

This week the trial period was up on the CAD design program. Today, the program was purchased and the Brain Stub design can resume.

Quantity of Stubs

Do we go with a quantity of redundant Octopus-like stubs or could the Brain could get by with one stub? Two stubs open up some possibility of grasping. One stub would be faster, cheaper, lighter, and easier to construct. It would consume less power, and remain easier to program.

Stub Focus

Focus is now on designing the shape of one Brain Stub.


The current idea is to use a PING))) kit for the interface connection to a constructed Wonder-Board Giant Brain Arm run by the large servo.


It's possible the Giant Brain Stub Arm could be 4-feet long and 1 or 2 feet in diameter. This is however subjective until the design is more solidified.


The shape is estimated to be grotesquely large, overbearing, ungainly, shocking, and with an appearance never before seen. It could have a very large hand at the end of the arm. But the hand would not be fully articulated. It must however meet the minimal requirements set forth in the previous Brain Stub post.


Should these servos mount standard or should they be continuous rotation servos? Maybe one of each - the large had could continuously rotate at the wrist (for some special functions) while the globby arm could dangle in varying degrees at the lumpy shoulder.

Possible Conclusions & Suggestions
  • A single Brain Stub
  • A blobbed shape never before seen
  • Made from manufactured WonderBoard
  • Interfaced with Parallax PING)))
  • Two degrees of freedom
  • Servo driven
  • A massively large hand
  • Side mounted
  • Articulation at the shoulder or elbow
  • Articulation at the hand wrist
  • Extremely large overall size ~ Four Foot extent
  • Grotesquely appearing
  • Light weight to minimize inertia
  • Programmed/Operated by the Brain Stem
  • Employing one continuous rotation servo at the hand wrist
  • One standard servo at the shoulder or elbow

We've opened up a new Question and Answer section that can be applied to posts. Click on contact and send your questions. Negative responses will be rejected. Constructive comments may be included with the project.

The first question comes from nThinker. Q - Can the Red Fist install on the SuperTronic Brain? A - Yes, it can install on most platforms with software for controlling a servo, but is specifically designed for a Propeller chip so it runs well on Supertronic ports or any of the Big Brain series and Propeller projects with an available pin.