Shipping the first thrusters this week!

Hello friends!

It’s been a while since we’ve sent out an email but a lot has happened – enough for several updates, so will try to send a few over the next few days. Everything is going great! Let’s start with the coolest news.

We are shipping the first 100 thrusters this week! Some have been shipped already and the rest will be in the mail by Friday. The shipments are mostly going to early-bird thruster backers as well as a few people who needed their thrusters as soon as possible.

Building 100 thrusters in a single batch is a big milestone for us and we want to share what was involved.

As you may remember, all of the thruster’s parts are custom, and we order them from all over the world. We still have to do a lot of work here in Redondo Beach to get the thrusters ready to ship.

First, here’s some of the “raw” materials as they arrive to us.

Some raw parts. Don’t be fooled by the small boxes. We have *18 boxes* of nozzles like the one at top left.

It’s amazing how much stuff we need to build all of the thrusters that you guys backed. We are literally up to the ceiling in boxes full of injection molded plastic parts. We have 1,000 cardboard tubes to package the thrusters in. We have 21,000 screws as well as thousands of other components including aluminum shaft collars, steel flux rings, and stainless steel motor shafts.

Wound and sealed motor stators.

The motor stators are wound and waterproofed elsewhere, fortunately, but we still do some extensive testing here to make sure that they are in great shape. Every stator spends at least three days in ocean water after which it is inspected for any signs of corrosion. Our supplier does a great job and the first batch had a 100% success rate.

We’ve been working hard the last few days to make sure that we could ship thrusters this week. Here are some pictures during the production process. We’re going to go into more detail about the tools and processes in a future post, so we’ll just show pictures of the in-process subassemblies here.

Stator bases while installing PCBs (left) and after stators and cables have been installed and sealed (right). The ends of the cables are sealed into the sealant so that water cannot leak through the cable and into your vehicle.

Here are the assembled and coated rotor assemblies. They consist of a steel flex ring road or base stainless steel motor shaft, and 12 custom arc magnets. They are coded in a tough protective coating that resists both abrasion and water.

Here are the motor cables, with the ends stripped and ready to be attached to the thrusters. The cable is a tough urethane jacketed cable that can handle abrasion and is very water resistant.

The Result

Here’s a pile of finished thrusters. Have you ever seen so many thrusters in one place??

Finished thrusters!

Each thruster is carefully packaged into a cardboard tube that protects it during shipping. The cardboard tubes are shipped in rectangular boxes for extra protection.

Each thruster is individually serialized and labeled. Here’s thruster #0001:

Each thruster comes in a protective tube and includes a counter-rotating propeller and mounting bracket.

Here’s all of the thruster tubes that are shipping this week!

Packed thrusters ready to go!

That’s all for now. Some of you will be receiving thrusters next week!

We’ll follow up with some more updates in the very near future. We’re going to cover the manufacturing process and tools, updates on OpenROV and BlueROV, and then talk about documentation, forums, and user contribution!

Things will be a little slow here during next week (Thanksgiving in the US), but we are expecting to ship the next batch by December 12th. If all goes well, we plan to have all T100s that were ordered without BlueESCs to be shipped in December. That will also include the OpenROV kits. We’re hoping to ship BlueROVs by early January.

If you have any questions/comments/concerns, please feel free to email us at info@bluerobotics.com.

First Test of the BlueESC

Here’s a video showing the first test of the BlueESC

This is our Rev.1 prototype. It’s not waterproof or integrated yet, but it works! Stay tuned for continued testing and development. All source files, schematics, and board layouts are available on the BlueESC Github Page.

SolarSurfer: Ocean Test No. 3

SolarSurfer in the ocean off the coast of Los Angeles

Two weeks ago we tested the SolarSurfer in the ocean for the third time.

We were fortunate to have access to a boat for two days and we successfully completed an overnight trip and covered 20 km.

Day One:

The boat was loaded with tools and the SolarSurfer and we headed out to sea, stopping about 1.5 miles offshore to launch the SolarSurfer. We spent a few hours debugging some small problems before we got everything working correctly.

Once we were confident that is was working properly and that it was clear of boat traffic near shore, we turned ourselves around and headed home for the night. The SolarSurfer stayed in the ocean and continued on its waypoint path out to sea.

Night:

By 6 in the evening, the power from the sun had reduced to almost nothing. At this point, the SolarSurfer had traveled about 6 km in 3 hours. The thruster automatically shut off and the SolarSurfer started to drift for the night. We ended up with a really interesting plot view of the surface currents that you can see in the map below. At first, it drifted towards shore and we were worried it would run aground before the morning, but then looped around. By the morning, it was fairly close to where it had started to drift.

Full screen here.

Day Two:

The SolarSurfer “woke up” and continued on its journey at approximately 8:30 in the morning, despite thick cloud cover. It continued its path westward until we turned it around with an updated waypoint command. We intercepted it with the boat around 11:30 am after it had covered another 4 km. Success.

Seaweed Entanglement Testing:

One of the risks we are most concerned about for the LA to Hawaii trip is seaweed entanglement. We tested some seaweed removal maneuvers that could be performed autonomously if necessary. The SolarSurfer was manually driven into a large piece of floating kelp and then driven in circles to entangle the kelp around the keel. In five tests, we were always able to clear the kelp from the keel by maneuvering forward and backward several times.

Seaweed tangled around the keel during testing. Removal was fairly easy.

Stay tuned for our next test and upcoming launch to Hawaii!

SolarSurfer: Ocean Test No. 2

If you haven’t seen it, we are building an autonomous solar-powered surface vessel with the BlueRobotics Thrusters. Check out more details at: Hackaday Project Site: SolarSurfer.

We completed the second test of the SolarSurfer in the ocean. Last time, we only had an RC receiver and we drove it around manually. This time, it had a full blown autopilot with GPS, compass, and an IMU.

We stored at set of waypoints in the autopilot’s memory. When switched into autonomous mode (via the RC transmitter) it automatically navigated between the waypoints. Amazingly, it was totally successful on the first try. Check out the map image that shows the waypoint path and the two test runs. There’s an interactive version here.

Thruster Test Stand

This post will show the thruster test stand used to measure thrust, rpm, and power. We’ll describe the test stand itself and a future post will talk about the electronics used to collect data.

Here’s the test stand in action.

Thrust test of a Thruster-100 generating about 5 lb of thrust.

We used a 40 gallon aquarium as our test tank but the test stand is designed to fit on smaller and larger tanks too.

The most important part of the test stand is an accurate load cell that we can measure the force of the thruster. It needs to be able to accurately measure forces in both the forward and backward directions. Unfortunately, the only load cells we could find to do this were hundreds of dollars. Instead, we added some weights to pre-load the load cell to about half its capacity and tare the sensor before making any measurements. The Measurement Specialties FC-22 is used. It is inexpensive and can measure from 0-25 lbf with +/- 1% accuracy.

Measurement Specialties FC-22

The Measurement Specialties FC-22 used to measure the thruster force.

A frame of extruded aluminum T-slot tubing sits on top of the tank. The thruster mounts to an L-shaped piece that pivots so that when the thruster produces forward thrust, it presses down on the force sensor. The weights are mounted on the same L-shaped piece to pre-load the sensor. When the thruster produces forward thrust it increases the force on the sensor and when it produces backward thrust it reduces the force on the sensor. A microcontroller measures the force as well as the voltage, current, and power being used by the motor.

Evolution of a Thruster

We’ve been working on the BlueRobotics Thruster-100 for almost nine months now. It started as a side project to replicate a commercial grade thruster but evolved into much more. We think it would be cool to share some of that process. This first post shows the evolution of the thruster design from day one until now.


We started by trying to replicate the “industry standard” commercial thruster design, which is essentially a motor sealed in a tube. A shaft extends from the end of the tube to attach to the propeller and a nozzle protects the propeller and increases the thrust. There’s several ways to create a sealed shaft: you can use sealed bearings with grease or you can use a magnetic coupling. Our first four design revisions used magnetic couplings to link the motor to the propeller through a watertight seal. Inside the tube, the magnetic coupling attached to an RC airplane brushless motor.

A few examples of commercial thrusters that inspired our original design.

We stuck with this design for our first four revisions but we ran into a lot of trouble. They had sensitive tolerances, expensive parts, and we needed steel ball bearings that would corrode in saltwater. We also had trouble finding an off-the-shelf brushless motor that had the high torque and low speed needed for a marine propeller.

Our first prototype, mostly hand machined on a lathe (left) and a section view of our Revision 4 design, showing the motor and radial magnetic coupling (right).

We decided that we needed to build our own brushless motor – one that had high torque and was very efficient. We built a number of test motors with different stators, windings, and magnets to find one that worked well underwater. In the process we imagined our current thruster design. Here is the entire evolution of the thruster design from day one until now.

What makes the new design different? It gets rid of the tube, seals, and couplings. Instead of sealing the motor in a tube, each part of the motor is sealed with a protective coating and the bearings are high-performance plastic. When running, water flows freely through the motor but it’s protected from short circuits and corrosion. Injection molded plastic parts from Proto Labs form the structure of the motor. It was a dramatic change from our starting point but it results in an affordable, high-performance thruster. For more info about the thruster design, check out the thruster page.

MakerCon 2014

We were fortunate enough to be invited to speak at MakerCon 2014 with Scott and Adam from Dragon Innovation during their workshop titled, “The Hardware Challenge: Going From Idea to High Volume Manufacturing”. During our portion of the workshop we described our journey from idea to prototype, the challenges we encountered along the way, and where we plan to go. We had a great crowd who had a lot of interest and questions for us!

The slides from that presentation are available on SlideShare and embedded below.

Be sure to check out Scott and Adam’s slides as well. They talked about some great stuff including how to select a factory, how to manage a factory, and how to do crowdfunding right.

bit.ly/Dragon-MakerCon-Introduction

bit.ly/Dragon-MakerCon-Crowdfunding

bit.ly/Dragon-MakerCon-Factory-Selection

bit.ly/Dragon-MakerCon-How-To-Manage-A-Supplier

The Thruster-100 is officially a “Cool Idea!”

BlueRobotics is excited to announce that our Thruster-100 has won the Proto Labs Cool Idea! Award.

We started development of Thruster-100 over 6 months ago as a side project after we had trouble finding a suitable thruster for an autonomous solar boat. We needed a reliable, rugged, and inexpensive thruster to power our boat for a 2-month long journey across the Pacific Ocean from California to Hawaii. We couldn’t find anything that fit our needs and, more importantly, our hobbyist budget. In our search, we found a number of people online who were looking for a similar thruster for their marine robotic projects. We set out to design a thruster that was simple, high-performing, and affordable.

The Thruster-100. (Image © ProtoLabs)

After 6 months and many prototypes, the Thruster-100 was born. And now, with the generous help of Proto Labs and the Cool Idea! Award, we can bring the Thruster-100 to you! With an affordable underwater propulsion system available to hobbyists, students, researchers, and commercial organizations, we hope to inspire and enable ocean exploration on a larger scale.

Exploded view of injection molded plastic parts. (Image © ProtoLabs)

Check out the official Proto Labs press release here!



Stay tuned for more updates and please join our email list to be the first to hear about the Thruster-100 release!