This was a very fun game, I enjoyed controlling the little guy. I just wish I had a bit more direction on what to do. I got to the stage where I could jump, but then after collecting all the ore previously inaccessible I was kinda just left wandering about, running into either dead ends or those enemy turrets/shields that I couldn't get past.
Also the first time I played I didn't realize at first the yellow/green marks on the ground were the ore I had to collect, so I ended up missing a few at the start. This led me to not realizing the upgrade pad was for at first since I didn't have enough ore to trigger it. And since I couldn't see a way back to the starting area without the upgrade, I was soft-locked to that section.
I think some visual indication for what you are supposed to do in the how to play screen and in game would be helpful. For example, when I picture ore I see individual rocks rather than veins meant to be drilled into. If the veins are the appearance you want to go for an image of that in the "how to play" section would be very helpful for new players who may not have the same mental image as you do for specific things essential to the game. Same for the upgrade pads. The how to play and controls pages didn't mention how you would be getting the upgrades, so on first glance I thought they were jump pads.
Apart from that, the game controlled very smoothly and I liked the appearance of the various stages of the little robot. Also liked the doors that you could only get through by speed boosting. It felt good to figure that out on my own. Nice work!