Table of Contents

Seminar On Self Assembly Robots Report Pdf Download

ABSTRACT

Self assembly robots have number of small modules(or robots) which can stick or bond together to perform various funtions. In this report bonding methods between modules of self assembly robots are analysed . Tests are conducted and the strength of the bonds for each method are presented for different module styles, bonding conditions and breaking conditions in a destructive test, and are compared with magnetic bonding methods.
For 80 micrometer modules, bond strengths of up to 500 mN are observed with thermoplastic bonds, which indicates that the assemblies could be potentially used in high-force structural applications of programmable matter, micro fluidic channels or healthcare. And finally simulation was performed using small magnetic modules to show the assembly and disassembly functions.

PROBLEM DEFINITION AND CHALLENGES

Recent work in reconfigurable robotics has involved the scaling down of individual robotic modules for increased resolution and access to small spaces. This has brought with it several challenges in actuation, computation, and module bonding . Many large scale modular robotic systems use traditional actuators such as dc motors or shape memory alloys to power the assembly, re configuring, motion, and disassembly processes using algorithms or motion primitives. However, as these systems are scaled down below the centimeter-scale, compromises must be made which reduce functionality, resulting in modules with less mobility.

Since the early demonstrations of early modular self-reconfiguring systems, the size, robustness and performance has been continuously improving. In parallel, planning and control algorithms have been progressing to handle thousands of units. There are, however, several key steps that are necessary for these systems to realize their promise of adaptability, robustness and low cost. These steps can be broken down into challenges in the hardware design, in planning and control algorithms and in application. These challenges are often intertwined.

Heating methods

A heating system is a mechanism for maintaining temperatures at an acceptable level; by using thermal energy. As you will see in the coming chapters, how are these method s are being used to form strong bonds with the neighboring modules.
We can heat the small modules of assembly robots using three methods, which have their own advantages and disadvantages. These methods are:
i) Heating by Peltier element
ii) Heating by focused laser
iii) Inductive heating by high power AC fields

Heating by Peltier element

The Peltier effect thermoelectric heat pump is a semiconductor based electronic component that functions as a heat pump. Just by applying a low DC voltage to this module, one surface gets cold and the other surface gets hot. And just by reversing the applied DC voltage, the heat moves to the other direction. Thus this thermoelectric device works as a heater or a cooler.
The Peltier thermoelectric heat pumps have been used for medical devices sensor technology, cooling integrated circuits, automotive applications and military applications.

DISABLING FOR MODULE ADDRESSABILITY

To add more magnetic modules to an assembly, each module is magnetically disabled after assembly, as shown schematically in Fig. 6.1. This process allows individual modules to be added to the assembly one at a time into arbitrary locations on the assembly without regard for the magnetic attraction or repulsion associated with that assembly location.Compared with bonding by magnetic attraction, this allows for a much wider range of assembly morphologiesto be made. New modules can be added to the assembly in any position or orientation. However, it is desirable to bond all modules with the same orientation so that they can be disabled and enabled as a group using a single global pulse.
Heat bonding of modules is accomplished by individual heating (i.e. by laser or inductive heating), or by global heating (i.e. heat
conduction through the entire medium).Once the assembly is completed, it is re-enabled magnetically and is free to move through the workspace as a single unit.

As further demonstration of the assembly plus heat activated bonding, a 2D ship-in-bottle morphology is created in a micro fluidic chip environment, as shown in Fig. 6.2.Creating a ship in a bottle requires individual modules to pass through a small opening (the bottleneck) and assemble into a ship shape one at a time. The simple 2D ship shape made here consists of nine modules, and consists of a hull,mast and sail. Such a demonstration shows the capability ofthe presented addressability, bonding and control method to achieve the creation of arbitrary shapes in remote inaccessible areas.