MENG 4450 · PLC & ROBOTICS

Saint Louis University · Fall 2026

Think out loud.

This site holds the interactive activities we run during class meetings. Each one is built for two people sharing one screen: you talk first, commit to an answer, and see the reasoning the moment you do. The reading gives you the principle, the bench gives you the hardware, and this is where the two meet.

Isometric illustration of an industrial automation cell with robot arms, a conveyor, and control electronics
Live

Ready to run

LiveDay one

Read the Syllabus

A card game in four rounds, refereed by Bolty the robot. Place the five weights, sort eight components by how each is graded, work through ten situations drawn from a pack of twenty-three, then finish with six lightning facts. Every answer traces to one sentence of the syllabus, and the sentence is shown.

Play →
LiveModule 2

Seal-In Simulator

The start-stop-seal rung with a panel in front of it. Hold Start and watch power reach the coil, let go and watch the circuit hold itself on. Stop the scan and step it by hand to catch the seal contact closing one scan after the coil, which is the thing you can never see in copper.

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LiveModule 3

How a Contactor Works

Eleven steps, with the mechanism on one side and the circuit on the other. Energize the coil and watch the armature pull in against the spring and every pole land together. Start a 480 V motor and watch inrush hit seven times running current. Stop it and watch the arc, then turn the shields off and compare. Then switch to our own bench contactor, four poles with two normally closed, and see 1.3 amps sitting under a 9.8 amp rating.

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LiveModule 3

What is a Pole?

Twelve steps from a bar magnet to nā‚› = 120 f / P. Bend the magnet into a horseshoe, put a rotor in the gap, wrap the ends round it, then swap the magnet for a coil and watch north and south appear a quarter turn away from the wire. Send a probe once round the air gap and count the sign changes. Pick 2, 4, 6 or 8 poles, switch on three-phase current, and count how many cycles one turn of the field takes.

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LiveModule 3

Three-Phase Induction Motor

Fourteen steps from one loop of wire to slip. Push current through a coil and watch the field arrow grow, add two more coils out of step and watch the field turn while the coils stay bolted down, hold the rotor and see current appear in bars that nothing is wired to, then let go. Drag the 3D view, step the clock a twelfth of a cycle at a time, load the shaft, and answer three questions along the way. A sailboat running with the wind explains why the rotor can never catch up.

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LiveModule 3

Single-Phase Induction Motor

Thirteen steps on why one coil cannot pick a direction. See the field swing on one line, split the swing into two turns that cancel, watch the rotor hum and sit still, then spin it by hand and see it keep going that way. Add a start coil through a capacitor and watch the switch cut it out at speed, or fit a copper ring on one corner of each pole and watch the field lean across the face. The last one is the bench gearmotor, and its slip settles near 12 percent.

Run it →
How to use

How these activities work

In class

One device between two students

Every activity is built for pairs sharing a screen, because the argument between the two of you is where the learning happens. Everything runs inside the page: open it and play, and when the tab closes, what it showed you is gone.

On any screen

Phones, laptops, the bench machines

Every interaction is a single tap, so the smallest phone works as well as a laptop or a bench machine. Open the link and you are in, and the whole room is playing within seconds.

What you get

Feedback, on the spot

Principle comes from the assigned reading, and grades live on Canvas. This site gives you immediate feedback while there is still time to act on it: every answer shows its reasoning, and syllabus questions quote the sentence they came from. Scores stay between the two of you playing.

Design rule

The answer is in the room

Wherever an activity can, it turns on something you read off the equipment in front of you: this bench, this pendant, this nameplate. Answering means standing in the room with the machine.