View source for Zoidberg II, powering robot fish

== '''Part 1: project profile''' ==

=== Project name ===
Zoidberg II, powering robot fish

=== Project short description ===
This project is aimed at designing, constructing and improving autonomous robot fish, starting from the ZOIDBERG project. It will be able to swim deeply in the water, to communicate and to orient in a free space thanks to several sensors mounted on-board.

=== Dates ===
Start date: 2008/11/01

End date: 2009/12/23

=== People involved ===

===== Project head(s) =====
Prof. Gini Giuseppina  - [[User:GiuseppinaGini]]

===== Other Politecnico di Milano people =====
Ing. Paolo Belluco - [[User:PaoloBelluco]]

===== Students currently working on the project =====
Andrea Parolina - [[User:AndreaParolina]]

Dario Simontacchi - [[User:DarioSimontacchi]]

Marco Perri - [[User:MarcoPerri]]

===== Students who worked on the project in the past =====
Francesco Milli - [[User:FrancescoMilli]]

Maurizio Mercurio - [[User:MaurizioMercurio]]

Alessandro Nava - [[User:AlessandroNava]]

=== Laboratory work and risk analysis ===
Laboratory work for this project will be mainly performed at AIRLab/Lambrate. It will include significant amounts of mechanical work as well as of electrical and electronic activity. Potentially risky activities are the following: 

Use of mechanical tools. Standard safety measures described in Safety norms will be followed. 
Use of soldering iron. Standard safety measures described in Safety norms will be followed. 
Use of high-voltage circuits. Special gloves and a current limiter will be used. 
Robot testing. Standard safety measures described in Safety norms will be followed.

== '''Part 2: project description''' ==
The project is composed by:

* State of the art;
* Preliminary studies and sketches;
* Design notes and guidelines;
* Description and results of experiments;


=== State of the art ===
The work that mostly influenced the design of our robot is a lower-scale automaton realized by Z. Wang, G. Hang, J. Li, Y. Wang and K. Xiao, which is actuated with the same type of SMA that we used.

It is discussed in:
[[media:Pesce SMA.pdf | A micro-robot fish with embedded SMA wire actuated flexible biomimetic fin]]


=== Preliminary part design === 

==== Mechanical structure ====
The design of the body has evolved into the current shape through many development steps, in response to the varying specifications of the on-board electronics, to changes in the manufacturing process of the hull, and for a better approach to the hydrostatic balance problem.

The first two images below represents the early proposed mostly flat design, and a step of the manufacturing of a "master" hull component in a modeling clay. The third image shows a simple prototype made of polyurethane foam, tethered to the tank for power supply. It can be noted the original configuration of the tail components, which were mounted in a horizontal fin arrangement with two parallel actuators.

<gallery>
[[Image:Forma_CATIA.jpg|First test body shape]]
Image:Modello_Poliuretano.jpg|Developed test body
Image:Modello_Plastica.jpg|Propulsion test
</gallery>

==== Electronics ====

The first version of the on-board electronics was a two-boards arrangement. Due to problems and delays with the company responsible of the manufacturing of said boards, there are no working exemplars of this solution. In the meantime the circuit has been redesigned and simplified to fit a single board, and we put together a very simple intermittent circuit to carry the first autonomous tests (without the robot being tethered to the tank).

Below are shown, in order: the original schematics of the two boards, the schematic of the oscillator used for the first tests, based on a 555 chip, and the intermittent circuit assembled on a prototype board.

<gallery>
Image:Schema_1.png|First board schematic
Image:Schema_2.png|Second board schematic
Image:BasicOscillator.svg|Test circuit (simplified) schematic
Image:Test_circuit.jpg|Test circuit
</gallery>

==== Videos of the actuator tests ====

Here are some clips, filmed during the first experiments trying to have a working actuator. The polymer and the electrodes are held in place by rough adhesive, and the power is supplied by an external generator. we are manually changing the polarity of the current going through the actuator.

{{#ev:youtube|kDF3zGa5b-c}}
*[http://it.youtube.com/watch?v=kDF3zGa5b-c External link]

{{#ev:youtube|xNAmuwDQzKU}}
*[http://it.youtube.com/watch?v=xNAmuwDQzKU External link]

=== Final design ===
(todo)
<gallery>
Image:FishBoard.svg|Final review board schematic
Image:Zoidberg_interno.jpg|The hull open, exposing the wiring
Image:Zoidberg_incapsulamento.jpg|Internal arrangement of the structure
</gallery>
<gallery>
Image:PesceUpWeb.png|Complete robot, top view
Image:PesceSideWeb.png|Complete robot, side view
</gallery>

=== Tests and results ===
(todo)

==== Videos of the robot in action ====

{{#ev:youtube|_L9oLe1OXiU}}
*[http://it.youtube.com/watch?v=_L9oLe1OXiU External link]

{{#ev:youtube|ptSdlPzTORw}}
*[http://it.youtube.com/watch?v=ptSdlPzTORw External link]