• aditya mehrotra.

redesigning chip: plan for redesign/process [updates]

So the first step in this of course is to come up with a plan that will work. In addition to just redesigning chip so it works we're going to be looking into making technology like that of legged robots (and other dynamic robots) both more useful as well as cheaper.

  • Actuators are too expensive, so we want to look at how to make those cheaper

  • How do we design the robot itself so that the parts are not so expensive despite being custom to the platform

  • How do we make it light and compact yet robust and strong enough to withstand development

To solve these above key problems, we drew out a strategy to tackle the redesign. We will systematically re-design the platform so we can ensure when moving onto the next step the system works well and as intended.

We're going to start be focusing on the actuation and communication technology. The below specifications are outlined:

  • Want to communicate w/ 12 motors over the CAN bus at high speeds

  • Want to control actuators such that we can do accurate Position + Velocity control as well as torque control

  • We want to be able to exert forces as well as mitigate impact forces etc etc.

The goal is to do this relatively inexpensively. So what we'll start with is a 1-DOF leg platform and we will develop jumping and landing for this leg. I think jumping will be easy, landing may be harder to get that impedance controller working. We'll likely look into Clarke and park transforms for motor control - these motors should have basic current control. We'll do all of this on the power supply giving us like 30A / motor.

  • We're also going to drop the gear reductions down to 10:1 instead of 100:1 like the are now

  • want to characterize the slop as well as other basic characteristics of the motors

  • Need to take 1/8" off of the shafts of the CIM motors to get everything to work properly with the gearboxes (for now we shimmed them but this was a bad idea to be honest

After we get this 1-DOF leg working we can talk about the 3-DOF regular chip leg and then move onto the rest of the platform!

****We will create detailed design docs for this version of chip in the hopes the platform will be good enough to "release" to some extent***

#updates #omgrobots #chip3

0 views0 comments
© copyright 2019 | aditya mehrotra