RaspiTank

Let's Make Robots Robots
1

It's a OVI arm with a old broken toy attached (a MOBAT battle tank, still on sale today). Everything is controlled by a Raspberry Pi with a wireless dongle and the camera module. It's possible to control it through a VPN like hamachi even if there's a bit of delay. The interface is made in Python and text only (using ncurses) so it can be accessed via ssh.

We added a servo, driven directly by the Rasbperry using servoblaster library, to maneuver the differential gear that gives motion to the tracks. The GPIO is interfaced with an optocoupler that activates some relays that turns on and off the various motors.Batteries for motors are 4 D rechargeable NiMH while the Raspberry is powered by a cellphone emergency charger.

It's messy but I had a lot of fun in building it.

The robot was recruited in a dance performance. The choreographer created a dance based on the peculiar movements that the objects do when they fall or are moved by the wind etc. and he wanted a real "object" to be in the show. The camera streamed projecting images on the wall, giving a usually impossible point of view of the performance.

This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/raspitank
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Great performance!

I plan to add an arm to my robot too and OWI arm sound a perfect kit to start with:)

I used wires scavenged by ethernet cables too, you can un-entwine them with a servo and get them straighter and faster!

On the first video the arm seems to have a loose grip, maybe you can add rubber or magnets to grip better.

Thank for posting it!

3

Thanks

The wires are from ethernet cables, indeed… maybe one day I will iron them :slight_smile: Servo untwining seems interesting!

Two rubber bands are provided with the arm, but the glue was not good and I lost them almost immediatly. Now I glued two strips cut out from the rubber used for chairs’ legs. Anyway, the arm isn’t very strong.

4

Thanks

double comment