Mini Hexapod

Autonomous Figure 8 (So Far)

This is a hexapod I've been working on for a while. It's a kit from Paul K. The hexapod uses HobyKing HXT900 servos. I was able to get the robot to successfully walk autonomously in a figure 8 pattern with all three legs on a side pointing the same direction (straight out). When I moved the corner legs so their starting positions were 60 degree from their neighboring legs, my IK code didn't work correctly. The hip angle of the leg is one of the parameters in the IK equation. I must of something in my equation incorrect since the equally spaced angle version of my code makes the robot dance in place.

There exists perfectly good IK code for this hexapod, but I've always wanted to see if I could figure the IK equations out on my own so I haven't used the other code yet. It seems like there are only a few hours a day that my brain works well enough to make some sense of the equations involved so I haven't yet fixed my IK code to deal with this 60 problem.

Paul K. sent gave me this hexapod hardware. Paul K. makes all sorts of cool stuff and I assume was looking for some feedback about a hexapod kit he was considering selling. Paul had seen my Popsicle stick hexapod (inspired by OddBot's "Chopsticks"). While my Popsicle stick robot was woefully under powered, I guess it showed Paul I was interested enough in hexapods that I'd probably complete his kit.

 

As Bajdi mentioned on his Bafdupod 996R page, finding regulators to power all those servos can be a problem. I'm presently using a pair of Dimension Engineering regulators. I use one regulator for three legs of the robot.

I've fond some other regulators that seem to work well and cost a lot less on ebay. I may switch to use these other regulators if they don't weight much more than the DE version.

I have a really cool four joystick remote from Paul K. I plan to use with this robot. I want to get the kinks out of my IK algorithms before I make the robot remote controlled so I'll likely wait a bit before adding an XBee for the remote.

I had previously planned to use Nordic nRF24L01+ module as a remote, but Paul's remote is made for the XBee and it doesn't have enough spare I/O pins to control a nRF24L01+ SPI interface.

Hopefully I'll have this robot walking again soon.

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Thanks for pointing out at me - nice hexapod you have there!

I am pleasantly surprised at the 9g servos having enough torque for it.

it's a good robot by the way!

it's a good robot by the way!

what are the servos you are using? i am trying to build a Hexapod robot, but someone told me 9g servos are too weak?

I'm using HobbyKing HXT900 servos. They're surprisingly strong for their size. The hexapod does need to be very light when using these small servos. The kit Paul gave me works great.

I initially tried to make by robot with craft stick. The craft sticks were much too long for the little servos.