Chase-boat motor test

Getting ready for the first test, we spent a few days going over testing equipment. Most challenging was fixing up the two outboard motors we have for our crash-boat Zodiac. We managed to get one of the motors started, but its cooling system wasn’t working. This video is of the second motor, which took longer to start, but has been working flawlessly since.

PCB Building timelapse

The PCB’s are now built and are just going through the first stages of testing. They are integrated into the boat and will be powered on shortly.

In the meantime, here is a video time-lapse of the build process.

New electronics PCBs

The second iteration of our electronics PCBs have come back from the manufacturer. We have made many revisions from the original design, and the complexity of the wiring in the computing box should be halved. Making the wiring less complex is essential in being able to diagnose when things go wrong.

Barnacle board v1.0
Barnacle board, secondary Arduino
Ahab v1.1, latest and greatest Arduino Mega shield
Ahab v1.1, latest and greatest Arduino Mega shield

We will be taking a time lapse of the construction process (soldering on all the components). Expect updates soon. Furthermore, we expect to have the boat on the water for its first test soon.

Progress update – Fully functional electronics

I’ve allowed too much time to pass since the last post, a lot of progress has been made since the last one.

Cleaner electronics layout
Cleaner electronics layout

The box with all the computing components has been cleaned up. We tested the current setup thoroughly and discovered some changes that need to be made to the custom circuit boards we use. More on that further down.

Better handling of power connections
Better handling of power connections

Part of the key was looking at how we managed power connections to all the components. We added boards with lots of connectors on them for powering components. Before that everything had to be screwed into the posts in the middle, which turned out to be really difficult to manage.

Support unit
Secondary Arduino support unit

We added a second Arduino (computer) to the electronics to handle some time-critical events that would have made programming difficult on the main Arduino. But the one pictured above is just for getting the prototype figured out, we have sent a new circuit board for manufacturing that will integrate the chip below.

A much smaller version of the secondary arduino
A much smaller version of the secondary arduino

We’re really looking forward to getting the circuit board that this smaller Arduino will fit into. It will clean up the electronics even further and allow more room for a couple other components we want to add.

One of the challenges, is knowing the position of the motors that control the sails, and exactly how much they are turning at any given time. We added a very accurate optical encoder unit to the bottoms of our motors. This way any movement will show up in the software that runs the boat.

Motor with encoder assembly attached
Motor with encoder assembly attached

Finally, here is the latest picture of the boat all set up. We performed a quick check on all the systems, and everything is turning out better than expected. All sensors and motors respond as expected, and software has been written to diagnose the state of everything so that we can be sure the boat is working when we test.

Boat in the bay for testing
Boat in the bay for testing

We plan to put the boat in the water soon. We had hoped to have the boat on the water already but have experienced some unfortunate mechanical issues. More on that in a later post.

New interconnects built and computer board manufactured

During the past weeks we have almost completed our overhaul of the boats electronic systems. We had a custom PCB made to manage all of the sensor and control signals supplied to the Arduino unit. The following shows the control board with supporting electronic “breakout” shields attached.

Control board with modules attached
Control board with modules attached

The idea is to make everything modular. Note the JST connectors on the left, each one roughly corresponds to one connector on the side of the electronics box. This way, removing things from the box does not require complicated re-wiring of existing components. This next picture shows the current contents of the electronics box.

Messy electronics management, a second revision will clean this up
Messy electronics management, a second revision will clean this up

Right now the box is very messy, and needs some more work before it can be cleaned up. A design revision of the control board is needed to accommodate an additional chip due to some changes we made to the overall design of the electronics. For now however, the entire thing is completely functional and still pretty modular, removing components is not a difficult task.

One major feature that has been added, are the connectors on the side of the box. These are waterproof industrial connectors with a solid latching mechanism that should prevent them from ever unintentionally coming undone.

ITT Cannon APD Series connector
ITT Cannon APD Series connector

New power management PCBs

Just received the first of several PCB designs from the manufacturer. This board takes the raw connections from the on-board batteries and provides several stable voltage lines that get fed to all the other compartments in the boat.

pwr_populated
The power board with all components soldered on

 

This isn’t the final version for one crucial reason. If one of the fuses blow, that’s the end of the boat’s journey. Our team is currently looking at different solutions to this problem, but until then, we can move the rest of the boats development forward without worrying about shorting our batteries.

The clean board fresh from the manufacturer, shiny laminated glory
The clean board fresh from the manufacturer, shiny laminated glory

Starting summer 2014!

We’re in the process of updating the site for the summer of 2014, expect more updates soon!

The summer of 2014 has begun, and we have a new plan and some progress updates from the school year to cover. We will continue to work towards completing the Microtransat challenge, and hope to eventually be the first University to put a boat this size across the Atlantic Ocean fully autonomously.

Currently we are working on improved electronic modules and wiring within the boat. We have designed one of three custom printed circuit boards which will be housed in three modules throughout the boat. The overall integration between the physical boat and its electronics has been refined significantly. Should one of the boat’s bulkheads flood for whatever reason, our electronics will remain operational. You can see the development of the project by going to our development page.

As we reach small milestones, such as the installation of new components, the results of component testing, expect new posts on this page.

Earlier this week, we took out the wind turbine that we’ll be using for power generation on board the boat, just to get a feel of how much wind was needed to get it spinning. We needed to pull it out of the cover of the surrounding buildings in order to get some consistent wind, but were pleased with the results overall.

Despite the majority of the work being done by the wind against the sail, we still need a way to generate power so that we can operate the drum winches and computer components. Given a large component like this, lots of testing and calculations need to be done to ensure the forces of the wind and water (in heavy waves) does not compromise the ships hull, in addition to testing how it will integrate with the ships electronics.