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intermediate · for college, institution

Robotic Arm 4-DOF

Servo-driven arm with inverse kinematics

Price on request

in-stock

Simulate it first

Request a quote for the price. The price excludes GST and shipping. Both are itemised on your written quote before you pay anything, and there are no other charges. Class-set pricing on request.

Gripper fingers: the end of the chainFour servo joints, J1 to J4Illustrative 3D render, not a photograph. J1 turns the turret on its bearing, J2 lifts the twin-plate upper arm, J3 bends the forearm and J4 rolls the wrist; a geared two-finger gripper closes on what it reaches, 280 mm from the base axis.

The numbers

Specification

Specification for Robotic Arm 4-DOF
ControllerAW-32, 72 MHz
Supply7.4 V, 2S Li-ion
Dimensions200 × 150 × 70 mm
Mass340 g assembled
Skill levelintermediate
Suited tocollege, institution
Availabilityin-stock
Assembly time2–3 hours

Figures marked in grey are draft and may change before the kit ships. Your written quote confirms the exact specification.

Try the control loop

Tune it before you buy it

A real PID loop, not an animation. Too little gain and it leaves the line on the first curve. Proportional alone holds the straights but lags on the bends. Derivative tightens the corners, integral closes the remaining offset. Then push the speed up and watch a tune that worked stop working.

120
0
0
60%

Try these

Error now
0 mm
Time off the line
0.0 s
Laps completed
0

Mean cross-track error across those four presets: 157, 83, 64 and 6 mm. The sensor bar is 90 mm wide, so anything past 45 mm has lost the line entirely. The same loop runs in the lab against the simulated kit.

Bill of materials

In the box

The most-read block on any kit page, so it is the most complete. Quantities are exact.

  • 1Chassis, laser-cut acrylic
  • 1Controller board, assembled and tested
  • 2Geared motor, 300 RPM, with encoder
  • 2Wheel, 65 mm, rubber tyre
  • 1Caster, ball type
  • 1Sensor array, 5-channel
  • 1Battery holder with protection circuit
  • 1Fastener pack, labelled by size
  • 1Assembly guide, printed

The contents list is indicative. Your written quote confirms the exact contents.

Why it is worth building

What you will learn

01

Closed-loop control

Tune a real PID against a real plant, and see what integral windup actually does to a robot.

02

Sensor calibration

Thresholding, ambient rejection, and why the value that worked yesterday does not work under different lighting.

03

Mechanical assembly

Fastener discipline, alignment, and the difference torque makes to a drivetrain.

Before you build

Simulate this kit in the Lab

Open the matching project, change the control loop, and watch what happens before a single motor turns.

Questions

Common questions

What joints does the Robotic Arm 4-DOF have?

The arm has four servo joints: J1 turns the turret, J2 lifts the upper arm, J3 bends the forearm and J4 rolls the wrist. A geared two-finger gripper sits at the end of the arm.

What is the reach of the arm?

The listed reach is 280 mm from the base axis.

Who is this kit meant for?

It is listed at intermediate skill level and suited to colleges and institutions.

Can I try the kit before buying it?

Yes. The Lab has a matching project where you can change the control loop and see the result in simulation before any motor turns.