Something doesn't look right on the animation,
since its still in progress you might already know this, but I'll just say it out :
The bot jumps up unnaturally 1px? on the 2nd frame.
Secondly, in a real world, just two legs cannot support the weight of a quad-bot that top heavy,
especially if its both front or both back legs at the same time, it will toppled or wobble aggressively.
it needs at least three legs to support itself. You might want to move the legs one at a time.
A slight suggestion, maybe make it look like its startled and slightly step back , instead of jump up.
You can check out some clips on youtube for reference on quad robots.
Maybe it'll give you some ideas.