TSATS: Technic Water Strider

[Splat]

Here is my entry for the 'To sail the Technic sea' contest: a Technic Water Strider (or 'gerridae').

Gerridae, or water striders, are anatomically built to transfer their weight to be able to run on top of the water’s surface. Water striders use the high surface tension of water and long, hydrophobic legs to help them stay above water. Gerridae species use this surface tension to their advantage through their highly adapted legs and distributed weight. The legs of a water strider are long and slender, providing the weight of the water strider body to be distributed over a much larger surface area. The legs are strong, but have flexibility that allows the water striders to keep their weight evenly distributed and flow with the water movement.

Source: http://en.wikipedia.org/wiki/Gerridae

You can see some more information about water striders and the way that they move on water in this YouTube video :

I originally wanted to use a Windup Motor but it didn't have enough power or enough turns when wound up (it has about 8 turns). I ended up using an M-Motor for propulsion, but the battery box is external and uses a tether to control the water strider. There is no steering in this model.

The mechanism that moves the middle and rear legs uses a modified version of Sariel's Octopod mechanism. The middle legs move in an elliptical motion, and have rubber tips to give them grip and help my water strider move forward when it is 'on land'. When my water strider is in the water, the rubber tips are replaced with 6x6 radar dishes that act as paddles or oars.

To get my water strider to float in water I used the hemispheres from the Death Star Planet set. The hole in the top can be blocked using a 1x1 round plate, and this provided enough floatation to stop my water strider from sinking when it isn't moving.

Unfortunately when my water strider is moving, or when the water is a bit choppy, the hemispheres on the rear legs flood and sink, so I had to use some ping pong balls for a little bit more floatation. This was a last minute solution to my problem, and I hope it is ok. I would have used the balls from the Mindstorms sets if I had any of them.

Here is a quick video of my Water Strider in action:

I took the video of the water strider in the fountain at the back of St Patrick's Cathedral in Melbourne, Australia (StreetView link). The fishing line in the video is just so my water strider didn't float away out of reach .

Here are a few more images of my water strider:

These photos and more can be seen in higher resolution in my BrickShelf folder (once they have been moderated/approved).

I have also created building instructions for this model if you would like to build a copy.

Edited April 10, 2013 by Splat

[bb15080]

great entry. something totally different

[Zerobricks]

Doesnt get more unique than that! Awesome, really great idea! Does it also walk?

[timslegos]

Definitely a solid entry! nice job.

tim

[efferman]

this strider has a very good chance to win. i love it

[Tomik]

Cool creation! Even I don't like insect much in real your strider is awesome and I think it would be great theme for Technic. I would like to see video that shows your strider's functions. Good luck in contest!

[Lipko]

I want one.

This is the mostest awesomest entry.

*one eye cries one eye smiles

[Splat]

@everyone - Thank you for your kind comments

On 4/1/2012 at 11:07 AM, Zblj said:

Doesnt get more unique than that! Awesome, really great idea! Does it also walk?

Yes, it sure does. I tried to mimic the movements that I saw in the YouTube video of the real water strider.

It's not too elegant on land, but it would be better on water (but I don't want to get my M-Motor wet).

On 4/1/2012 at 0:54 PM, Tomik said:

Cool creation! Even I don't like insect much in real your strider is awesome and I think it would be great theme for Technic. I would like to see video that shows your strider's functions. Good luck in contest!

Thanks Tomik. I have created a quick video that shows how this Lego Technic Water Strider 'walks' (please see the video I added to my opening post).

Edited May 30, 2017 by Splat
Fixed missing link after forum upgrade.

[Finntech]

There's so many great and stunning entryes in this competition, but this water strider is my personal favorite. It looks so real, I bet my wife would be scared to see that thing on the kitchen table!

Good luck.

[PaulBaldowski]

That is awesome. I used to collect a lot of Technic because of the incredible building potential - but this sort of thing blows any thoughts I might have had right out of the water. I would pay through the nose to get a set like this - official or otherwise. Well, I would, but I'm not sure my wife would approve!

[Zaiocrit]

Very nice !

[Mas Bambang]

Beautiful creation!

[grohl]

This is just pure awesomeness.

[Milan]

One of my three favourites!

[Thelonious monk]

absolutely amazing, one of my favorites. Very original idea and well executed!

[Splat]

@everyone - Thanks again for your kind comments 

On 4/3/2012 at 7:07 AM, grohl said:

This is just pure awesomeness.

@grohl - I have admired your work for a long time, especially your organic models (I love your prey mantis), so your comment really means a lot to me.

Entry update:

I took my Water Strider out today and took some photos and a video of it 'walking on water'. I have updated my opening post accordingly.

I have also updated the video that I had, so be sure to watch the second half of the video (the 1st half is the same, in the 2nd half you can see it 'walk on water').

Once again, thank you all for your kind comments, and I wish everyone 'good luck' in the contest.

@Siegfried (aka Sinner) - Firstly, thank you for organising this contest.

I have updated my opening post to only show seven images and one video. I thought that is was important to keep the source photo of a real water strider for reference, so I have kept that in my post, but it is included as one of the seven images. If there is anything else I need to do to fix up my entry please let me know, otherwise consider my entry finalised (and the photo that you have used in the index is perfect).

Edited May 30, 2017 by Splat
Fixed missing link after forum upgrade.

[DLuders]

Cool MOC!

Edited April 10, 2012 by Sinner
Removed duplicate video

[efferman]

what does he use for these white balls/ cylinders?

[Omikron]

what does he use for these white balls/ cylinders?

Could be this

[Splat]

Cool MOC!

Thanks DLuders. I have included that video in my opening post too.

what does he use for these white balls/ cylinders?

Could be this

That is exactly correct. They look white on the video, but they are actually LBG. There is a small hole at the top, but you can seal the hole with a 1x1 round plate, or anything with a single stud. There is no bottom, but they act similar to a diving bell where they trap a bubble of air to provide floatation. I have updated my opening post with more details.

[efferman]

very clever solution

[Darth Dino]

Hi

as biologist i really have to comment your Incredible MOC. Iam a specialist in beetles (not bugs) but the shape, the dimensions and sizes are very precise. I really like to looknof the torso and head. Even the angles of the legs are quite good.

I would recommend that MOC for the contest hust for the look and design.

But it has a working functionallity that makes it even better! Veyr well done!

Dino

[Splat]

very clever solution

Thanks efferman

Hi

as biologist i really have to comment your Incredible MOC. Iam a specialist in beetles (not bugs) but the shape, the dimensions and sizes are very precise. I really like to looknof the torso and head. Even the angles of the legs are quite good.

I would recommend that MOC for the contest hust for the look and design.

But it has a working functionallity that makes it even better! Veyr well done!

Dino

@Dino - Thank you very much for your kind words

[Combee]

This is so cool! Great job on the model and I'm very impressed that you actually made it work!

[Splat]

This is so cool! Great job on the model and I'm very impressed that you actually made it work!

Thanks Combee, and thanks for the votes