Protei sensors and actuators

     

The picture above shows the different sensors and actuators which are needed to sail a sailing vessel autonomously. Also is shown which principles are implemented by the Protei team already.

Actuators:

Protei focused mostly on the actuators, therefore almost all actuators are already present in the prototypes build by the community. We will not use the shape shifting hull in the design of our tool to test the intelligence, therefore the bow and stern steering meganism will not be present in our design and will be replaced by a more conventional rudder. Also the height of the sail is not adjustable in the protei prototypes so far. This is something which makes the durability of the sailing vessel better by being able to het zeil laten zakken during a storm. However we will probably not implement this in our prototype.

Sensors:

The protei community only build one prototype; protei_005.0 with working electronics, but this was a very small vessel which couldn’t really sail and because of this wasn’t really tested. In later prototypes only the GPS receiver was kept and the sailing vessel was completely remote controlled from ashore.

In this prototype we want to find out if a sailing vessel can autonomously sail, therefore sensors are needed to provide the system with the necessary information. Most of the sensors; GPS, wind speed and wind direction come very naturally. But along with these sensors also a gyroscope is necessary to know the angle of the sailing vessel with the water to be able to adjust the sails according to the weather conditions. The water depth sensor is another feature which is important to prevent collision with shallow waters, this can eventually be solved by using gps and waterdepth maps, but this needs investigation. Also there is a meganism necessary to measure how saturated the oil boom is, so the sailing vessel will know when to return to the mother ship and change the oil boom. This is also a feature which will probably not implemented in protei_009 which will only address intelligent sailing.

1 day prototype: Banana-boat

This is a one day prototype for the Protei project (opensailing.org) Made at the Eindhoven University of Technology (Faculty of Industrial Design). Photo's are made by Pieter Bron.


The idea

Exploring different ways of steering while maintaining the maneuverability of the boat was one of our first iterations to start-up our project. Brainstorming sessions resulted into the concept of the Banana-boat.

The idea is that the front of the boat is rounded and shaped upwards, providing lift when the boat is moving forward. Upon taking corners, the front will rotate 90 degrees to the left or to the right, putting a rounded rudder in the water, resulting into the boat taking a corner.




Parts List


Foam
Wooden keel (Filled with heavy weight-stuff -> approx. 1,5 kg)
Wooden cylinder
Iron bars (Sail)
Iron rings (Sail)
Fabric (Sail)
Tie Wraps
Duct Tape








Construction of this prototype


Sail
Cut an iron bar with a length of 55 cm. Cut another iron bar with a length of 30 cm. (Diameter of 2.5 mm was used on our prototype) Now solder the 30 cm iron bar on the 55 cm, at a distance of 10 cm at one end of the larger bar. Solder it 1 cm from the end of the small bar.


Measure the required size for the fabric. (Differs per fabric as some are more elastic than others.) Then, punch 6 holes in the fabric where the rings should go. (Look at upper picture for reference.)


Punch iron rings (Grommets) in the holes, leaving you with the following.

Note: One of the holes is still missing here. See earlier picture for sixth grommet position.


Use tie-wraps to connect the 5 grommets on this picture with the iron bars. Finally, solder a third iron bar right between the other two iron bars and connect the sixth grommet to it with a tie-wrap.


Boat
Use foam to construct the boat. Construct a shape that looks like the following picture.

Length is approx. 60 cm. Rudder is 10 cm, diameter of the hull is 8 cm. Next, cut this construction in half. Create a wooden cylinder with a thickness of approx. 3 cm, with the same diameter as the hull. Create a hole on top of this cylinder and punch your sail in it. Connect the cylinder with the rear side of the boat. Glue/duct tape/however you wish together.


Create two more slightly curved rudders. Glue these on the front part of the boat, in line with the curve in the boat itself. Glue them on a 90 degrees distance from the main rudder. Connect it up with the unused side of the wooden cylinder by sticking an iron pin inside the cylinder, then punch the foam front on this iron pin so it can rotate.


Keel
Create a wooden keel, fill it with lead (approx 1,5 kg) an stick it on the opposite side of the wooden cylinder compared to the sail.

Thats it, your boat is ready! Pimp it, should you wish.


Testing

Facts
- This boat does float
- It is possible to steer the boat with this type of rudder.
- The sail catches wind and creates forward motion of the boat.

1 day prototype: Shifting hull (robot snake)

This is a one day protoype for the Protei project (opensailing.org). Made at the Eindhoven Universitiy of Technology (faculty of Industrial Design).
Movie by: Pieter Bron

The Idea
With this prototype, we wanted to explore the shape changing hull as it was introduced in earlier Protei boats. To do this we decided to build a hull that moves its body like a snake. The hull is made of foam and its movement is controlled by servos attached to an arduino.

Parts list:
Foam
Steel rods
Elastic bands
Servos + wiring 
Arduino

Building;
We constructed six equal pieces of foam for the snake’s body, a head and tail where also added. 
As shown in the sketch below, the servos are placed in a mirrored pattern.This was done for better weight distribution and it was easier create snake-like behaviour. 

With a scalpel, holes for the servos where made;

Then a hole was made in every segment through which an elastic band was fed. This band keeps all segments together. In the back and front the elastic band is held in place by a rod that is pierced through the band.

For the joints, we tried different things;

First we tried making the joints form soft foam, this turned out to be to flexible. The joint being to flexible caused the snake to bend also in different directions as it should.

In version 1 of the prototype (see movie) we used square joints made of the same hard foam as the rest of the body is made of. These joints worked better but made the movement of the snake a lot less smooth. Therefore we chose to use triangular joints (version 2 in the movie).





From this prototype we learned about the mechanical properties a shifting hull needs (the importance of the joints)
If we are going to use this technique in the future we should look into using less servos to make a complete body move (with energy efficiency and simplicity in mind).

User testing assignment

In this assignment we got the first introduction of what the upcoming quartile will look like for this assignment.
We will apply different methods on the user tests we will perform this quartile.

The reason for user testing is evaluation, does the design provide a good mapping between the goals of the project and the product and if the mapping is wrong, what caused this? e.g. incorrect assumptions or unpredicted behavior. With this user testing we are able to find out about the users' world and engineer towards a target. For this evaluation there are different methods available.

In this assignment we will focus on three methods:

Paper prototyping:
By using simple paper prototypes nothing is pre-defined by the design and the user is free to interact with the prototype in the way he thinks suits him best. In this way you can find out which things are missing in your design and how you can adapt function in such a way they are logic for the user.

Co-discovery:
With this method, 2 users will simultaneous discover the product and will discuss how the product works and help each other out to solve problems they would stumble upon and in this way reduce the total amount of errors they would have if they worked on this task alone.

Think aloud:
this method is very similar to Co-discovery, participant are asked to think-aloud while they are performing a list of pre-specified tasks. there is also a method talk-aloud where users are asked to only tell which actions they perform instead of interpreting.

introduction and first contact with client

Today I got a first introduction of the project and the client. 

especially the client meeting was interesting. They expect us to build a 1 meter long prototype of our own version of Protei. During the pressure cooker this week we will generate ideas how to do this and produce our first small prototype. 

Starting point for Protei is to be able to produce a low-cost, high efficiency, self-autonomous and unmanned vessel capable of cleaning oil trails on the ocean. The objectives are the following:

 

-          Unmanned

-          Sustainable

-          Unsinkable

-          Fast Development (They want a solution for the near future)

-          Affordable

-          Open Hardware

The things i'm interested in is if the movement in the hull of the vessel is the best way to change the direction of the ship and maybe even if using a sail in the first place is the best option for Protei. 

Ideas I have at this moment about this topic is to have multiple vessels connected to each other with more to steer the oil absorbent from behind as well as from the front so there is more control also this can maybe increase efficiency. Also a complete different hull design is possible. This is something which can be addressed during the pressure cooker this week.

During the skype meeting with Piem Wirtz, I got to know how the Protei open source community works and was decided that I will be the main contact person for the Protei project.

Also we got invited to show our work on the Dutch Electronic Art Festival together with the protei team of Piem Wirtz. We are still considering this offer, so if we will show our product will be announced in the future.

At the bottom is a 7 min. video about the protei project.