Follow on Instagram

solve/robotics

Robot interview questions, solved.

12 questions · 12 simulated robots · 5 models you can play with

Each reel ends on a question with four options and no answer. The answers live here: watch the robot, commit to a guess, then open the solution one step at a time.

Start with question 1Browse all 12
Start here
#1 · Dynamics · UR5e armThis robot arm weighs 20 kilos. So why can it only lift five?Easy #6 · Dynamics · Skydio X2How far can a drone lean before it starts to sink?Medium #10 · Dynamics · Unitree Go2Motors strong enough to backflip. So why does it slide off a ramp?Medium
All questions
0/12 solved
1. Why a 20 kg arm only lifts 5 kgThis robot arm weighs 20 kilos. So why can it only lift five? Dynamics UR5e arm Easy labvideo 2. Turning radius of a two-wheel robotThis warehouse robot has no steering wheel. So how does it turn? Kinematics Warehouse robot Easy labvideo 3. How late can a drone brake?This drone is flying at a wall at 36 km/h. How late can it brake? Dynamics Skydio X2 Medium labvideo 4. The walk-to-run speed limitWhy can't this humanoid just walk faster? Physics sets a hard limit. Locomotion Unitree G1 Medium labvideo 5. How hard should a gripper squeeze?How hard should a robot squeeze? Too soft, it drops it. Too hard, it crushes it. Manipulation Franka Panda hand Easy labvideo 6. The steepest lean a drone can holdHow far can a drone lean before it starts to sink? Dynamics Skydio X2 Medium video 7. How far the capture point jumpsA walking robot gets shoved. Where must its next foot land? Locomotion Unitree G1 Medium video 8. Perfect in sim, falls on hardwarePerfect in simulation. Falls in two seconds on real hardware. Same policy. Why? Sim-to-real Unitree G1 Hard video 9. One joint at 1,000 degrees a secondThe hand moves at 10 cm a second. So why does one joint spin at 1,000 degrees? Kinematics UR5e arm Hard video 10. Backflip motors, sliding off a rampMotors strong enough to backflip. So why does it slide off a ramp? Dynamics Unitree Go2 Medium video 11. Hand still, elbow swingingThe hand is perfectly still. So how is the elbow swinging? Kinematics Franka Panda Hard video 12. 5 mm too high, 200 newtonsThe table is 5 mm too high. So why does the robot press with 200 newtons? Control Kinova Gen3 Medium video
Latest reels
14 Nov 2026 · RoboticsPraxis-1: Runway's robot brain is openRunway just put the weights of its robot-control model out in the open. 14 Nov 2026 · AI hardwareIntel's AI GPU has 480 GB of memory and no HBMIntel just made an AI GPU with 480 GB of memory and no HBM. 14 Nov 2026 · AI newsByteDance says it is still behind the US labsByteDance’s co-founder Zhang Yiming reportedly told the company’s AI team at an internal all-hands that they’re still behind the US labs, and that reaching the... 13 Nov 2026 · PuzzlesPlanetary Parade, part 4: The tower twist 13 Nov 2026 · PuzzlesPlanetary Parade, part 3: Your odds are 1 in 44 13 Nov 2026 · PuzzlesPlanetary Parade, part 2: 7 circles, 44 skies
All 27 reel notes
You commented, here it is
SETUP 15 Nov 2026 · Comment SETUPThe 3-file setup every vibe coder needs (template)A rules file so the AI stops forgetting your project, a .env file so your keys never reach GitHub, and a plan file so it asks before it builds. Copy, fill in, done in five minutes.15 Nov 2026 · NetworkingOpenWrt with an Airtel, Jio, BSNL or ACT connection: what actually worksYou almost never flash the box your ISP gave you. You put your own OpenWrt router behind it. Here is how that works on each of the big Indian ISPs, and which routers to buy.CHECKLIST 15 Nov 2026 · Comment CHECKLISTPushed an API key to GitHub? The checklistWhat to do in the first ten minutes after a key goes public, in the right order, and the four-line setup that stops it happening again.KIMI 15 Nov 2026 · Comment KIMIThe trillion-parameter sizing sheet: will Kimi K2.6 fit on your GPUs?Every number from the reel, where it comes from, and the three formulas you need to size any model yourself. Opens in Google Sheets or Excel.CHIP 15 Nov 2026 · Comment CHIPThe AlphaChip paper, the rebuttals and Google's reply, in one placeGoogle says an AI has been laying out its TPU chips since 2021. Other researchers say it loses to a 1980s algorithm. Here are both sides' papers, in the order they came out, with what each one actually claims.
All freebies
From the blog
15 Nov 2026 · NetworkingOpenWrt with an Airtel, Jio, BSNL or ACT connection: what actually worksYou almost never flash the box your ISP gave you. You put your own OpenWrt router behind it. Here is how that works on each of the big Indian ISPs, and which routers to buy.15 Nov 2026 · Research noteThe formula says 5.1 m. The simulated drone took 6.3.A textbook answer and a simulated drone disagree by more than a metre. The gap is 0.16 seconds long, and it is the part of the answer that gets you the job.14 Nov 2026 · Behind the reelsHow the robot reels are made: nothing is animatedEvery robot in these reels is a physics simulation, and every number on screen is read from its log. Here is the pipeline, and the rules each question follows.