Universal Robots simulator — learn URScript free in your browser
Write real URScript on a simulated UR-style e-Series cobot arm, run pick-and-place with live physics, and learn frames, TCP, I/O, the gripper, and cobot safety — with auto-graded lessons, from zero. No install, no robot, no vendor license. Play free in your browser; go Pro for the full course and a certificate.
The robots
What are Universal Robots?
Universal Robots (UR) makes collaborative robots — cobots — six-axis articulated arms designed to work safely alongside people without the cages a traditional industrial robot needs. The current e-Series family spans the UR3e, UR5e, UR10e, and UR16e, which differ mainly in reach and payload but share the same kinematics and the same programming model. Their friendly programming and large community make UR the most popular on-ramp into robot programming.
You program a UR in two complementary ways. PolyScope is the graphical interface on the teach pendant, where you jog the arm and build a program tree of waypoints and nodes. URScript is UR’s underlying text language — movej, movel, movep, set_digital_out, and more — which runs on the controller and is what every PolyScope program ultimately executes. Learning URScript is the fastest way to truly understand how a UR moves.
Our simulator
A browser-based UR simulator that teaches real URScript
Our Universal Robots simulator puts a 3D UR-style arm in your browser tab. You write real URScript — the same commands a UR controller runs — and the simulator parses it, solves the inverse kinematics for each pose, plans the joint trajectory, and runs the motion under physics. Grab a part with the gripper and it follows the tool; drive into something and a collision is detected. Nothing to install, no virtual machine, no robot, no license.
Crucially, the lessons are auto-graded. Each task defines success — place the part at B within tolerance, no collision, under a cycle-time budget, within the cobot force limit — your program runs, and you get specific feedback on what to fix. That goal-based grading is what turns watching into learning.
Real code
You write the same URScript a real UR runs
No drag-blocks-only toy and no invented pseudo-language. A first pick-and-place program in the simulator looks like this — and the exact same commands run on a physical Universal Robots controller:
# Pick a part at A, place it at B
set_tcp(p[0,0,0.15,0,0,0]) # tool centre point: 150 mm gripper
set_payload(0.8) # 0.8 kg part in the gripper
movej(home_q, a=1.4, v=1.0) # joint move to a safe home pose
movel(pick_approach, a=1.2, v=0.3) # linear move above the pick
movel(pick, a=0.5, v=0.1) # straight down onto the part
set_digital_out(0, True) # close gripper
sleep(0.4)
movel(pick_approach, a=1.2, v=0.3) # lift straight up
movel(place, a=1.2, v=0.25) # linear move to place B
set_digital_out(0, False) # open gripper
movej(home_q, a=1.4, v=1.0) # return homeThe simulator parses this, solves the inverse kinematics for each target pose, plans the joint trajectory, and runs it under physics. movej moves fast through joint space; movel keeps the tool on a straight Cartesian line; movep holds a constant tool speed through blends — the distinctions every UR programmer has to learn, shown live.
Honest comparison
URSim vs a browser learning simulator
These tools solve different problems, and the best workflow often uses both. URSim is the official tool for building real programs; ours is the fastest way to learn URScript before you get there.
URSim (official)
Universal Robots’ own offline simulator. It runs the full PolyScope and UR controller in a Linux virtual machine, so you can build and validate complete production programs on your computer and deploy them to a real robot. It is the right tool for serious offline programming — it is just heavier to install and configure, and assumes you already know the robot.
Our browser simulator (learning)
A zero-install simulator that opens in a browser tab on any computer. It teaches URScript from zero with guided, auto-graded lessons and a 3D UR-style arm. It is not a replacement for URSim’s full program development — it is the learning on-ramp. Many people start here, then move to URSim once the fundamentals click.
In short: URSim = full official offline sim for real programs; this = the free, browser-based way to learn URScript with graded lessons. Complementary, not competing.
Safety first
Learn cobot safety — protective stops and payload
A collaborative robot is only collaborative when it is configured safely. The simulator teaches the safety behaviour that defines a cobot, so you build the right instincts before you ever stand next to a real arm.
Protective stop
When the arm meets an unexpected over-force contact, it stops — a protective stop. Learn what triggers it, how to recover, and how to plan motion that avoids nuisance stops.
Payload & TCP
Set the payload mass and tool centre point correctly. Get them wrong and the arm misjudges its own dynamics; the simulator shows how payload and TCP affect reach, accuracy, and safe speed.
Speed & force limits
Cobots run within force and speed limits when sharing space with people. Practise keeping moves inside those limits while still hitting your cycle time.
Safe approach motion
Use approach waypoints and linear moves so the tool comes onto a part predictably — the habit that keeps real cells collision-free.
What you’ll learn
From first jog to a graded pick-and-place cell
The course takes you from never having touched a robot to programming a working, collision-free pick-and-place cell — every lesson graded against a real goal.
Jogging & frames
Move the arm in joint space and in Cartesian space; understand base vs tool frames and how the TCP is defined.
Your first moves
movej vs movel vs movep — when each is right, and how speed and acceleration change the motion.
Digital I/O & gripper
Read and set digital signals; open and close a gripper to actually pick something up.
Pick-and-place A→B
The core skill: approach, grasp, lift, traverse, place, release — the backbone of real cobot work.
Waypoints & blends
Chain waypoints with blend radii for smooth, fast cycles instead of stop-start motion.
Payload & TCP
Configure payload and tool centre point and see how they change reach, accuracy, and safe speed.
Collision & safety
Cobot protective stops: trigger and avoid over-force contacts; respect safety planes and speed limits.
Graded capstone
Palletise four parts into a pattern — no collision, under cycle time, within force limits — and earn the pass.
Pricing
Free to play, Pro to master
Play in your browser for free — write URScript and run the simulated UR arm at no cost, no card. Go Pro to unlock the full graded course end-to-end and earn a certificate of completion. Same login as our PLC simulator.
Keep exploring
More robot programming resources
- Robot programming course — the full graded curriculum, from first jog to capstone.
- Robot arm simulator — how the six-axis arm and kinematics work in the browser.
- Universal Robots programming — a deeper guide to programming UR cobots.
- Robot simulator — the overview of our browser robot simulator.
- Learn URScript — the full syllabus, a commands cheat sheet, and a code-to-motion walkthrough.
- What is URScript? — the language explained from scratch.
- How to program a Universal Robot — a step-by-step walkthrough.
Universal Robots simulator FAQ
Program a Universal Robot in your browser.
No install. No robot. No license. Real URScript on a simulated UR-style e-Series arm — free to play, graded from zero.