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Should Underwater Thruster be Cheap?


(Hadoo) #1

Hello,

I’d like to bring the forum’s attention to the a analyses on Underwater Thruster price. First let us have a look on some well known underwater thruster on the market:

1- tecnadyne 260, Thrust 5 Kg, Max input power 350 w, a complete set price starts from 3800$
2- Lian Innovative, Thrust 5 Kg, Max input power 170 w, a complete set price stars from 2300$
3- Bluerobotics, Thrust 5 Kg, Max input power 350 w, a complete set price is about 150$

4- Seabotix, Thruster 5 Kg, Max input power 450 w, a complete set price is about 850$

In the first view It is the Bluerobotics that wins the game. it is much cheaper than the others. But let us have deeper view on all choices.

tecnadyne is an old company with professional reliable products nobody can doubt about their quality, but the price is high and most of the customers can’t afford it.

seabotix is another well known old company. But its technology is old, the motor is brushed, the efficiency is the lowest, but the price is much cheaper than tecnadyne. Also there is a few models that some one can select the best one.

Bluerobotics price is excellent. But it is a new born company and their thrusters have lots of unreliability, seaweeds can stop the thruster. The efficiency is low and there are just two models that some one can select from.

Lian Innovative is mature company. Its price is moderate, the efficiency is best and reliability is the highest. There are more that 30 models and variations. Seaweeds, Fish hitting, Fishing nets cant stop it. And there is no short term maintenance.

By the way let us consider price. I’d like to bring your attention to the price. operation cost of an off shore team, Including, Boat (or ship) some personnel and . . . are fairly expensive. In professional mission it could be more than 15 K US$ per day. What would happens if the mission is unsuccessful. 15 K$ fly. Too bad.

Here the reliability come to account. For project managers, it is unacceptable to loose this money and one day, just because of a seaweed!!! But let us be fair, for hobby that there are no personnel cost, off course Bluerobotics is the best choice.

It’s upon to you. Are you going to be hobbyist in the future or be a professional underwater robotic expertise in the future?


(Richard) #2

Hadoo,

Each of us who pursue the building of a “practical” ROV has a unique, to us, reason for doing so. In my case it is to provide a platform to carry a video camera to the bottom of the ocean; a very simple, but practical reason. In my case I couldn’t afford to do that until I discovered Blue Robotics products and customer service. End of story.

Richard


(Hadoo) #3

Richard,

Is it possible to go down to the bottom of the ocean just 5 Kg of thrust??? Are you kidding?

A small ROV needs Couple of 10 Kg to be able to overcome the water flow.

Hadoo

 


(Harold Scadden) #4

Can’t resist on replying. First your post sounds like an advertisement for a company in China and your profile states that is where you are from too. Second, Richard summed it up perfectly in his response.

The BR thrusters and products are not something designed for high end use at this point in time. What it is … is a great intro product for people who have never messed with an ROV and don’t have a huge bank account. Are the products perfect? NO, are the products good? YES Is there room for improvement … YES and this holds true for anyone’s product line.

The crew and BR has done an outstanding job of going from a Kickstarter item to creating a product line that is great for the market it is intended for.

Just a comment on going to the bottom of the ocean, you don’t need thrust to do that. Ballast can put you on the bottom in a matter of time. You need thrust to overcome whatever current might exist at the depth band that you are in and just like with the atmosphere that is variable. I have had products that I have made go on platforms that have been to the bottom and back again. Another comment on the thrust being low, I have seen acoustic decoy’s used to keep torpedoes from killing you have less thrust than the T-100 and do just fine for the job that they were intended on doing.

 


(Richard) #5

Hadoo,

I, in fact, reduce the thrust on my x-y plane T100’s, it is too much for my usage! I do that by mapping my PWM to 1300-1700 usec. At full thrust, the 2 T100’s propel my ROV at over 6 knots! The most current I have experienced to date where I dive is about 2 knots. I mapped to the smaller band to reduce sensitivity in turning with the joystick. I do, though, keep my vertical T100 at full thrust capability. I am currently running USR1 ballasted 18 ounces negative buoyancy. The T100 hardly breaks a sweat giving me a hover at depth. I found that by ballasting negative and using the thruster for hover I have better control, and I get down to depth faster which reduces the affect of current.

Question: do you have actual experience operating small (less than 20 pounds displacement) ROV’s at ocean depths? The theoretical world of small underwater ROV’s, including swimming pool testing, and the reality in the ocean can be significantly apart.

Regards,

Richard


(Whit) #6

This post showed up over at the Parallax Forums too…


(Harold Scadden) #7

Then it was as I expected. Blasted Ad. I went to the page of the so called “best choice” motor and for a Chinese site that is trying to appeal to English speaking customers, they should get someone who understands the language to write it for them because their grammar and everything else is horrible. The other thing is that the website domain has only been alive since 24 December 2015. According to the various material on there the company was started back in 2000 by three high school students who now have 23 engineers working for them.

Frankly I smell a rat as in a ripoff site. I reviewed everything I could find on there and the place just sets off my warning flags. They might be legit, but I would still be real paranoid before sending them any money.

Domain Name: LIANINNO.COM
Registrar: REALTIME REGISTER BV
Sponsoring Registrar IANA ID: 839
Whois Server: whois.yoursrs.com
Referral URL: http://www.realtimeregister.com
Name Server: NS1.US14.SITEGROUND.US
Name Server: NS2.US14.SITEGROUND.US
Status: ok https://icann.org/epp#ok
Updated Date: 15-mar-2016
Creation Date: 24-dec-2015
Expiration Date: 24-dec-2016

Why would you only register your website for ONE YEAR if you are a business and you have been around for a while?

 


(Paul) #8

Same posts in various groups on Facebook. I believe this type of post is commonly referred to as “trolling”. LOL


(Harold Scadden) #9

I wish they made anti-trolling cruise missiles … I would stock up and launch often!

 


(Hadoo) #10

Dear Harold,

Not fair in your judgment. The blurobotics also expires in less than one year.

But I think let the visitors decide upon their knowledge. Lian Innovative products is obviously professional, not suitable for hobbyist. Have a close look on the picture, and its link.

Regards,

  • Hadoo

 

 



(TCIII) #11

Hadoo definitely posted an infomercial for his product which is pretty crass.

If his products have quality similar to HK’s, then look out.

As Richard has pointed out, I doubt that you would see the kind of support that has been provide by Rusty and the BR crew from a Chinese supplier who usually sell it and forget it.

Regards,

TCIII AVD


(Harold Scadden) #12

@Hadoo the domain for that site was just created this past December. Why did it take so long for a company that has been around for 16 years to get a website up? I can understand name changes etc. but there was nothing in the history of the company to indicate that.

As for being fair, how about not posting, as TCIII stated, infomercials on other vendor sites. I wouldn’t buy their product just for the fact of sleazy advertising methods. Facebook etc. is fair game. On another vendor’s site that is total bull in my book.

Your post, in my opinion, was not slanted as a comparison contrast of various thrusters but as a pointed advertisement.