Abstract— The paper talks about a new innovative way of “swarm co-ordination” or “Shape Changing” system. The system is called Magphere. In this system a new swarm co-ordination system is defined which works on the principle of MegProp. The system works on spheres (shape not just limited to sphere but can be cubical, ellipsoid, polyhedral etc too) having computer at core and electromagnets arranged along the whole surface. These Magphere spheres can communicate with each other using wireless technologies and co-ordinate the points of bonding to join with each other to produce movement or to form bigger organism (robots) shapes. These Magpheres can also carry other equipment’s for their mission like plugs to get charged midway in mission or camera or bomb etc. The paper explains how the Magphere technology can revolutionize the robotic and other associated fields of science. Paper also talks about how Magphere can be developed and the initial experimentation that has been done.

I. INTRODUCTION he Swarm robotics is a relatively new kind of field in robotics where a multiple, mostly simple physical robots

coordinate among themselves to form a multiple coordinated robot system. This approach got its inspiration from biological studies of ants and insects in the field of nature, where swarm behaviour happens, which led to artificial swarm intelligence. A group of swarm robots are supposed to show a desired collective behaviour emerging out of co-ordination between them or with environment.

Many scientists around the world are working on it. But swarm is still considered the thing of future because till now no best solution is yet formed about how these robots interact and bind together to form a big organism that can climb or walk or do other chores. The two most popular works in swarm robotics is done by University of West England and Swarmanoid project co-ordinated by Prof. Marco Dorigo and funded by European Union. But both of these projects are researching on creating mechanical connection between robots which are mostly just rectangular in shapes. With present technology (providing mostly mechanical connections between robots), it is hard to create such miniature robots which may have enough power and an inter-connection mechanism to form bigger organism

Manuscript received September 25, 2013. This work at present is not

supported by any Govt or non-governmental organization. However a patent was filed on Magphere system in September 2013. Magpheres: The electromagnetically co-ordinated swarm “robotic/shape changing” system.

Author Tejinder Singh is an Aeronautical Engineer cum design Engineer cum Software Engineer. (phone: 0091-0172-2666052; e-mail: teji.catia@gmail.comm & teji.conf@yahoo.com ).

(robots) through coordination. To solve these problems associated with swarm system a new Magphere system is invented and is being developed which gives a new kind of co-ordination system resulting in a new swarm technique which makes swarming lots less easy. We will describe how Magpheres gives advantages in how the different robots can co-ordinate in any dimension. Let us now first take a look at some of prominent projects that were undertaken on swarm robotics system:

A. Swarm-Bots Project The project was aimed at providing an application where self-organization and self-assembly can be used in a classical Search & Rescue in complex environment. A swarm of about 35 s-bots were studied so that they can transport a heavier object from its initial position to a goal.

Fig. A: S-bots trying to transport object to goal by avoiding obstacles.

In above figure at the right side you can see a yellow goal location; on the left side there is a grey object to be transported with the help of s-bots. The problem has many several possible paths through which object can be transferred from the initial to the goal location. The possible paths had different lengths and required obstacle avoidance and holes. The weight of the object was such that its transportation required a coordinated effort of at least n s-bots, where n>1. The overall scenario can be split into two main tasks: finding an object or a goal location, and performing cooperative transport. The robot was conceptually modular at all levels w.r.t mechanics, electronics and software. Mechanical modularity was achieved by stacking modules on top of one another, following well-defined specifications. The modularity of the electronics was achieved by partitioning the required functionality of each module to make them as independent as possible. You can find its full description at [2].

B. Swarmanoid Project The Swarmanoid project is the successor project to the

Magpheres: The electromagnetically co-ordinated swarm “robotic/shape changing” system

Singh Tejinder, Member, SAE

T

International Conference on Individual and Collective Behaviors in Robotics

978-1-4799-2813-2/13/$31.00 ©2013 IEEE 98

Swarm-bots project, and is built on the results obtained during the Swarm-bots project. The goal is to construct a heterogeneous swarm that can move in 3D space. The project consists of 3 kinds of robots: -Eye-bots : they provide an aerial view to detect the objects of interest and to direct the actions of other robot types. -Foot Bots : A foot-bot is an autonomous robot that improves over the s-bot platform, previously developed within the Swarm-bots project [2], [3], [4]. The robot is conceptually modular at all levels: mechanics, electronics and software. Mechanical modularity is achieved by stacking modules on top of one another, following well-defined specifications. -Hand Bots : A hand-bot has no autonomous mobility on the ground, but is able to climb standard office furniture, grasp small objects such as books or letters, and bring such objects to the ground. For a swarmanoid to transport an object, the hand-bot can grasp the object while itself being transported by the foot-bots. The hand-bot can thus interact physically with other robots of the swarmanoid. As you can see the above systems is kind of an idea of how swarm systems should be but they do not lay out basic mechanical coordination system which will truly make swarm system a truly capable system. To answer it a new Magphere system is developed which provides advantages in how the robots can co-ordinate in any dimension they desire. To understand Magphere, we must first understand Megprop system as described below. The full description of MegProp is available at [1] [5] [6]

II. BASIC PRINCIPLE OF MEGPROP VEHICLE

Take two magnets and a sheet of cardboard. Place one magnet M1 above the sheet and one magnet M2 below. If you will move the magnet M2, the magnet M1 will also move. You can test it by placing a toy car with ferrous base above any cardboard. Place a magnet below the cardboard surface on which toy car is standing. Now if you will move magnet along the surface of cardboard, the toy car will also move along. This is the basic principle of MegProp vehicle.

III. DETAILED WORKING OF MEGPROP VEHICLE

A. Figures

B. Detailed Working Based on Figures

1) FIG. 2: Figure shows isometric view of MegProp car resting stationary over road. Each box represents an electromagnet.

2) FIG. 3: Figure shows top view of the MegProp vehicle resting. Electromagnet boxes are arranged in an array. Box with no color represents an inactive electromagnet. The vehicle body is not shown. Only the area, which the vehicle will occupy, is shown in red color. The boxes with red color represent electromagnets which are active. For giving reference number to electromagnets, the column are marked as A,B,C etc and rows are marked as 1,2,3 etc. So B1 marks

Fig. 2 : MegProp car resting on road

Fig. 3: MegProp car resting Fig. 4: Car moves forward.

Fig. 5 :Car moves more forward Fig. 6:Car moves to right & fwd.

Fig. 1 MegProp car concept through a permanent magnet. A car with ferrous base is above the tray. On the base of tray is a permanent magnet. If permanent magnet is moved to any direction, the car also moves along.

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electromagnet in 2nd column and 1st row and so on. The column A here don't have any electromagnets but only BC2’s(Box Controls), spaced 20 rows apart. Poles are being shown in figure with yellow colors. These BC2 takes instruction from central computing system and then passes instructions about which set of electromagnets to activate in the road. If CCS(Central Computing System) decides to move forward. The instruction of the CCS will be sent to BC2 which will in turn activate the magnets in front of vehicle and the ones at the rear will be deactivated which will move the vehicle forward. In figure 3 vehicle is stationary (the vehicle is standing over area in color red) with electromagnet set (C25, D25, C26, D26, C27, D27, C28, D28) just below the vehicle marked in red color being active. Means electricity is flowing to them only and rest of electromagnets are not supplied with electricity.

3) FIG 4: To move car forward,CCS via BC2 will activate two electromagnets(C24, D24) in front and deactivates two electromagnets (C28, D28) in the rear. The active set of electromagnets is now (C24, D24, C25, D25, C26, D26, C27, D27). The time gap of activating electromagnets is defined by the velocity which CCS decides to be given to the vehicle. The more rapid the electromagnets are activated the more fast the vehicle moves.

4) Fig. 5: Shows vehicle still moving forward. The active set now is (C23, D23, C24, D24, C25, D25, C26, D26).

5) Fig. 6: Shows vehicle moves forward and then to right so at end he is at (E20, F20, E21, F21, E22, F22, E23, F23).

So in this way vehicle can be maneuvered in any direction.

IV. DETAILED WORKING OF MAGPHERE SYSTEM

A. Figures

B. Detailed Working

The Magpheres will be in the shape of spheres mostly but can be in cubical, cuboid, ellipsoid, polyhedral etc shapes too. But for illustration purpose we will use spherical shape only.

From section 2 you must now be familiar with Megprop. In Magpheres we will use same principle of Megprop. But here instead of putting electromagnets on road, we will put small electromagnets all along on spherical surface area. Like take a look at Fig. 7 where each circular tablet on sphere represents small electromagnet. The power and

Fig. 9: Three Magpheres coordinating among themselves so that the Magphere at south moves to North.

Fig. 10: Multiple Magpheres coordinating among themselves to form complex structures

Fig. 7 : The Front & Isometric view of Electromagnets on Magpheres

Fig. 8 : Two Magpheres attached at a point. The future points of contacts are also shown in different colors.

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instructions (ON/OFF) to electromagnet will come from battery and mini-computer that lies at the core of the sphere.

With internal sphere circuitry this sphere can turn any single or multiple panels on Magphere surface ON or OFF. Using which Magpheres can move w.r.t. each other or on any ferrous surfaces. Let’s have a better look at how movement is generated through co-ordination.

Co-ordination between two Magpheres: Check figure 8.

Let’s suppose we have two of these Magpheres. Let’s suppose electromagnets are arranged as in a fashion as shown in the figure. The two spheroids will get bonded together at some panel (ON State) due to magnetic force. Now suppose we make these attached panels go OFF and make a nearby pink panel ON at both spheres. Then the two spheres will roll and get attached to each other at these new pink panels. And then we can put the Pink panels to go OFF again and activate green panels. Spheres will get attached at green panel now. Afterwards we can make Magpheres get attached at brown, then red, then blue panels. We can go on switching nearby panels ON or OFF, so that the two spheres keeps moving with respect to each other.

Co-ordination between 3 Magpheres: The co-ordination

between two spheres does not produce as much a good resulting movement that can be useful for our purpose. But three Magpheres can provide a better movement. Let’s suppose we have 3 of these spheres as shown in figure 11. Let’s suppose the two spheroids get bonded together at some panel due to magnetic force. Now suppose a third spheroid is at one end of one of other Magpheres so that the 3 Magpheres make a straight line from north to south as shown in Fig 9. In this configuration we can make a south Magphere move to north. Let’s see how. We know mass and inertia of two spheres will be higher than single one. Now if a nearby (to the right) electromagnet is turned ON at middle Magphere and south Magphere, the south Magphere will move to a side of middle sphere as shown in Fig 9(2). We can then move electromagnetic ON area further and south sphere will move more toward north. And hence at end it will become the North Magphere. The previously north Magphere will become middle Magphere and previous middle one will become south Magphere. We can continue repeating this movement of south Magpheres to North. So that the spheres can move w.r.t each other to collectively appear to move in a single line toward north.

Co-ordination between 4 Magpheres: The three

Magphere movements can still not be in straight line due to law of action and reaction. But in 4 Magphere, the action-reaction can be minimized with higher weight at rest of 3 Magpheres when 4th one is moving from South to North. The 4 Magphere arrangements (the movement will be similar to above described between 3 Magpheres. Just a 4th(the southernmost) moves w.r.t. other three.), we can have heavier static mass of inertia of 3 spheres, so that 4th one

move without disturbing the position of other three. Co-ordination between multi Magpheres: We have

seen in chemistry that multiple elements of a compound can bond together to form amazing structures. Similarly multi Magpheres can arrange themselves in any shape they desire, because they can bond to multiple other Magpheres at any position on their surface as they like. See Fig 10 for a sample shape. Using these shapes the Magpheres can coordinate and perform various actions described in next paragraph.

Magpheres climbing walls, stairs or Slopes: The

Magpheres can co-ordinate between themselves and can climb stairs or walls or slopes or anything just like ants coordinate among themselves. Because the Magpheres can arrange themselves in any shape they like, they can even form an Eiffel tower like structure shown in figure 10 to climb walls. These Magpheres can co-ordinate between themselves using various wireless technologies like Bluetooth, wi-fi, GPS etc. Some of them can even carry hidden plugs to get charged during the mission by finding electrical points nearby. Or some of them can have cameras for providing way to other Magpheres or themselves or for reconnaissance. The possibilities are endless.

Movement of individual Magpheres: The Magpheres

can move individually too if they like. They can use existing technologies like shifting their own center of gravity or gyroscopes etc if needed for a mission to move as single piece. Also if they find a ferrous surface, then each one can use Megprop electromagnets to roll on surface by itself, even if the surface is vertical, or upside down. More on it is described in next section.

Shape of Magpheres: The shape of Magpheres is not just

limited to Spheres. It can be in cubical or ellipsoid or polyhedral etc shapes too. But the principle will remain same, i.e. to use Megprop.

V. DETAILED WORKING OF INERTIAL SYSTEM OF MAGPHERE’S

A. Figures

Fig. 11: The isometric and front cut-section view of Magpheres inertial system when pendulum is at center.

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B. Detailed Working There are many kind of spherical robots that have been

invented that move individually. These have not been studied for as much for swarm system though, because co-ordination between them was not possible with present mechanical systems. The Magpheres will provide that co-ordination system. So to solve the purpose for individual movement of sphere, we will use the already existing technologies that are used in various spherical robots. For our purpose we will be using pendulum to provide directional control.

We have thought of a system of a rotating pendulum for our Magpheres as shown in figure 11 and figure 12. These figures show the half cut-section view of Magphere so that you can see the internal functioning. The Magphere is shown in blue color; the electromagnets are shown in red color; the motor and its rotating shaft are in brown; the pendulum is shown in yellow color; and actuator to move pendulum is in green.

At the start, the pendulum will be resting and so will be the sphere. To move sphere forward, the motor will start rotating the pendulum. Every action has an equal and opposite reaction, so the sphere will start moving in opposite direction to that of the rotation of pendulum. If we let the pendulum rotate at 90 degrees to the rotating shaft (Fig. 11), the Magphere is expected to roll in straight line. To move the ball to the right or left, the actuator will be used to tilt the rotating pendulum in a direction to which the Magphere needs to be directed. So using Motor, Pendulum and Actuator we can move single Magphere in any direction.

Just to mention. The pendulum where center of mass is far away from center will produce less angular momentum then if the pendulum lied at center. But we still chose to keep center of mass away from center so that higher stability can be provided when we want the Magphere to be stationary. We will later experiment with center of mass being at center also.

VI. EXPERIMENTATION Until now we have tested with a single electromagnet. We

have tried to make it go ON/OF through output from Arduino Uno board, getting its instructions from a coded

program on a laptop.. The circuit that was choosen is as described below :

We have tested the circuit with a small electromagnet of

12V and 250mA. Going further we will test with multiple more electromagnets which should all be controlled through Arduino board. We are right now planning a better circuitry.

VII. CONCLUSION The swarm robotics is relatively new field. The new

Magphere system provides the coordination system that will solve many challenges associated with the swarm system. The ability to get attached to other swarm robots without mechanical connection offers a new shift in robotics. These swarm robots-Magpheres have the potential of acting in co-ordination or by themselves. Coordinated effort is possible with the use of Megprop system. And the already existing technologies pave the way for movement of single Magpheres by itself. With Magphere the swarm robots can potential show the same functioning as is displayed in nature like that of Ants. The advances in Artificial Intelligence will further make the dream of Magphere swarms system possible. At present the idea is in nascent stage, but it has a lots of potential to be refined further.

REFERENCES [1] Singh Tejinder, www[dot]megprop[dot]com [2] F. Mondada, G. Pettinaro, A. Guignard, I. Kwee, D. Floreano, J.-

L.Deneubourg, S. Nolfi, L. Gambardella, and M. Dorigo, “SWARM-BOT: A new distributed robotic concept,”Autonomous Robots, vol. 17, no. 2–3, pp. 193–221, 2004.

[3] M. Dorigo, “SWARM-BOT: An experiment in swarm robotics,” in Proceedings of the 2005 IEEE Swarm Intelligence Symposium (SIS-05), P. Arabshahi and A. Martinoli, Eds., 2005, pp. 192–200.

[4] M. Dorigo, E. Tuci, V. Trianni, R. Groß, S. Nouyan, C. Ampatzis, T. Labella, R. O’Grady, M. Bonani, and F. Mondada, “SWARM-BOT: Design and implementation of colonies of self-assembling robots,” in Computational Intelligence: Principles and Practice, G. Yen and D. Fogel, Eds. IEEE Computational Intelligence Society, New York, NY, 2006,ch. 6, pp. 103–135

[5] Singh Tejinder, “MegProp system for city rail-roads”, in proceedings of 2011, 14th International IEEE Conference on Intelligent Transportation Systems (ITSC).

[6] Singh Tejinder, “Alternate Transport using Magnetics”, in the proceedings of 2010, CONAT conference held at Brasov, Romania

Fig. 13: The circuit to control single electromagnet through Arduino Uno getting its coded instructions through laptop.

Fig. 12: The isometric and front cut-section view of Magpheres inertial system when pendulum is tilted to change direction of movement.

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