Hexapod uses mechanical advantage wisely.
I like his use of 9g servos, it keeps the weight and cost down, but he uses mechanical advantage to make up for their lack of power.
https://youtu.be/bIjOvqGbMKA
https://youtu.be/bIjOvqGbMKA
Comments
Linkages are def the way to go. That little 12-servo biped also used 9g servos & linkages.
It's 18 servos. For some reason 16 jumps of the tongue (and fingers) easier. I often have to correct myself on how many servos a 3dof hex has.
I've watched that video many times. I love the way he's got the IK nailed. I also like how manages to control the hexapod with a single microcontroller.
The linkages have their pros and cons. Of course you can increase the torque using the linkage but it comes at a cost of reduced range of motion and it also loses some of the "cool" factor by having additional wires on the legs.
While I think Stubby is a great hexapod, I personally don't like the look of the extra linkages.
It's been a couple weeks since I've mentioned my hexapod so if anyone reading hasn't watched my hex in action make sure and check out the video in post #73 of my Halloween Hex thread.
I've got the moving in any direction and rotating the robot figured out but Stubby still has me beat on being able to tilt the robot. Adding tilt to the mix complicates the IK a lot.
https://hackaday.io/project/770-stubby-the-teaching-hexapod
It's all open source! Very cool!.
One of these days I'll probably read through the code to see his equations.
I notice that youtube has started automatically segueing to videos similar to the ones just shown. That makes me wonder: what might you end up with, diggity-six videos later, if you leave the page open overnight? I'd be tempted to try it, but I'm not sure I trust the mechanism not to take me into sketchy territory -- or worse.
-Phil
There's an "Autoplay" switch that you can turn off so that it doesn't automatically move on to more videos. It's located in the upper right side above the other videos.