• aditya mehrotra.

chip updates: tomorrow's plan [updates]

Yesss that's right, from tomorrow we're getting back to doing some work on chip! Before we continue the greenhouse project because my body is honestly hurting (updates on that later). But YES back to chip and we're going to review the plan we came out with before because it's incredibly important we do these things properly.

Finally... after ten minutes of scrolling here it is: https://www.adim.io/post/chip-updates-control-design-for-the-new-code-version-updates


- First we're going to measure chip's total weight (and include weight of planned


- Second we're going to do an experiment where we figure out where the CoG is at a

given set of leg positions (described later)

- Then we'll go into the control design of the current system and start implementing

things with the IMU using feedback-control instead of GUESSING

- Come up with some way to account for SLOP in the system

The Experiment to Measure CoG:

Our biggest problem is the X location of the CoG, we have no idea where that thing is. In the Z-direction we don't know exactly where the CoG is but we can measure it and then assume it doesn't change very much. In the Y-direction we kind of don't care where the CoG is.

So here's what we're going to do. We're going to measure the Z-Cog on its own, and then we'll create a function that tells us based on the position of the legs where the X-Cog is through measurement. Only movement of the TOP LEG really affects the CoG (the Theta1) so we're just going to do a really accurate measurement of that. This is the best way to model a system if you actually have it. Don't know where the CoG is? MEASURE IT!

So the experiment here would be to use the classic, balance this on a POLE experiment. You might say that's primitive, and you'd be right. But it WORKS. Sometimes if something is too complex to model you need to go back to the basics. And if we can build this kind of model we'll be able to control the robot (hopefully).

So that's what we're going to do.


All this stuff is pretty important to get the control system working, we need to know where the CoG of the robot is, we need to use the IMU, we need to know how heavy chip is because that'll help gravity calculations and etc. We've also described the procedure to measure the CoG above, experimental data, if we have the physical robot and we can do this, it will be way more accurate than modeling.

So tomorrow we're going to do a lot of design and planning, measuring the CoG especially because we can do that (I don't have a scale so we can't get the weight just yet but)...

We want to, tomorrow, create some sort of timeline for the project as well as goals and the defined features we're going to have and how to do them. Tomorrow is planning day. (what will we use the IMU for and etc), plan out EACH control mode and so on. I'm too tired to do that tonight, that's why I'm leaving it for tomorrow.

Hereee we goooo

#updates #omgrobots #chip #chiptwo #yay #chip_in_for_good

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