Propeller-guided, paddle-wheel-driven ASV

Phil Pilgrim (PhiPi)

Here's a video of the first sea trial of the ASV (autonomous surface vehicle):



In this video, it's RC-controlled, not GPS-guided. It was pretty squirrelly to operate. It needs a fin and a more refined velocity curve to tame it. But I'm satisfied with its maximum speed.

More to come ...

-Phil

mindrobots

Brilliant! It looks like a very excited duck learning to swim!

(Yes, it needs a centerboard)

Peter Jakacki

I dub thee "Flapper".

Phil Pilgrim (PhiPi)

I guess I should explain: "Why paddle wheels?" I've used underwater thrusters from Blue Robotics before. Their thrusters are really great and very reasonably priced. But on a surface craft in this area they suffer from fouling on floating -- or barely submerged -- seaweed. I've found that paddle wheels are less susceptible to fouling, albeit at the expense of efficiency.

-Phil

erco

Fabulous! Brilliant! Love the boogie board!

Pretty sure this is the first time I've actually heard PhiPi's mellifluous voice.

Another winner, PhiPi! Will your students be following in your footsteps?

Phil Pilgrim (PhiPi)

erco wrote:

Will your students be following in your footsteps?

I'm actually following in theirs, in a way. This is a blend of two student projects, from three and four years ago. The first was an ASV driven by underwater thrusters; the second, an RC paddle-wheel-driven catamaran. I discovered in the second project that paddle wheels are much less likely to foul than thrusters, hence the ASV design revision. I'm still considering ducted fans or propellers, though, which would completely eliminate the fouling issue -- excepting deadheads and bull kelp, of course.

BTW, today I added a small rear fin and modified the velocity curve from square to linear. It performed with much better controllability. This evening, I performed a compass calibration -- a deadly-boring, very tedious operation. But it's important, due to the proximity of two permanent-magnet, brushed DC motors. Tomorrow, I should be ready to tackle autonomous navigation.

-Phil

AwesomeCronk

You could make basic modifications to a BOE-Bot RC Nav program and mount the board on here. It would probably work well!
Coolest paddle-board I've ever seen!

Publison

AwesomeCronk wrote: »

You could make basic modifications to a BOE-Bot RC Nav program and mount the board on here. It would probably work well!
Coolest paddle-board I've ever seen!

It's a Propeller based project, and I'm sure Phil will run circles around a BS2.

AwesomeCronk

I'm a fan of the BS2. Still do not completely understand the Prop1(or Spin1). I am learning to develop windows apps faster than I am learning Spin. Probably because my stuff is in boxes.

Whit

Awesome work Phil! (as always)

Great to hear the "real-time" evaluation by you in the background with the gulls and other birds...

Ken Gracey

AwesomeCronk wrote: »

I'm a fan of the BS2. Still do not completely understand the Prop1(or Spin1). I am learning to develop windows apps faster than I am learning Spin. Probably because my stuff is in boxes.

BlocklyProp is the fastest way to go from PBASIC to Propeller. I think it'll make a lot of sense to you. Come program in cartoons with us.

Ken Gracey

Phil Pilgrim (PhiPi)

The GPS nav that I tested in the marina, based on an old program, went sort of okay. What was supposed to be a straight path was sinusoidal (over-correcting), and there was some indecision at the turn-around point. But it eventually went where it was supposed to.

I'm going to change the algorithm completely. Basically, it will be a line-follower, but the line will be a virtual itinerary defined by the waypoints. It's easy to compute which side of the line you're on and how far away. Heck, even Blockly could do that!

-Phil

Ken Gracey

Phil Pilgrim (PhiPi) wrote: »

I'm going to change the algorithm completely. Basically, it will be a line-follower, but the line will be a virtual itinerary defined by the waypoints. It's easy to compute which side of the line you're on and how far away. Heck, even Blockly could do that!

-Phil

This must be when I come in

Right when you think I'm not paying attention. Ya know, Mr. Pilgrim, although May wasn't a very productive month for me there's a good chance I'll make it up there for a competition!

Phil Pilgrim (PhiPi)

Ken Gracey wrote:

... there's a good chance I'll make it up there for a competition!

Yesss!

-Phil

lardom

Phil Pilgrim (PhiPi) wrote: »

...BTW, today I added a small rear fin and modified the velocity curve from square to linear. It performed with much better controllability. This evening, I performed a compass calibration -- a deadly-boring, very tedious operation. But it's important, due to the proximity of two permanent-magnet, brushed DC motors. Tomorrow, I should be ready to tackle autonomous navigation.

-Phil

I'm going to follow this. I have tried to imagine a design that could hover in one spot sort of like a drone and move in any direction independent of the craft's orientation.
Even if I'm asking too much I think it's a fun project. Thanks for posting the video.

Mark_T

Phil Pilgrim (PhiPi) wrote: »

erco wrote:

BTW, today I added a small rear fin and modified the velocity curve from square to linear. It performed with much better controllability.

I was about to say "that thing could benefit from a keel to reduce sidesways drifting", I presume that's not needed with
a fin. Another possibility is to add a disc to each paddle to provide lateral stability and enhance amphibious capability.
Nice craft.

Whit

Phil,

Time for a research trip? Ken is invited too!

Phil Pilgrim (PhiPi)

Whit,

Thanks for the photo!

One of my memories from childhood is a camping trip on the Ohio River in our Scout leader's Chris Craft. As we were motoring along in near darkness, the Delta Queen passed us, all lit up. She was magnificent! Perhaps that memory has been an unconscious inspiration.

-Phil