intermediate · for college, institution
Robotic Arm 4-DOF
Servo-driven arm with inverse kinematics
Price on request
in-stock
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.
The numbers
Specification
| Controller | AW-32, 72 MHz |
|---|---|
| Supply | 7.4 V, 2S Li-ion |
| Dimensions | 200 × 150 × 70 mm |
| Mass | 340 g assembled |
| Skill level | intermediate |
| Suited to | college, institution |
| Availability | in-stock |
| Assembly time | 2–3 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.
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
Closed-loop control
Tune a real PID against a real plant, and see what integral windup actually does to a robot.
Sensor calibration
Thresholding, ambient rejection, and why the value that worked yesterday does not work under different lighting.
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.