Focus This Week

This week is focused on System Integration. The goal was to package and integrate all previously developed sub-systems (the steel chassis, 3D printed casing, molded steering grip, custom dashboard, motor driver PCB, throttle sensor, and battery pack) into a single, operational mechanical and electrical vehicle assembly. I completed the structural assembly of the Electric Go-Kart Car, built the power distribution network, wired all sensors, and verified active driving logic.

Group Assignment — System Assembly

The group assignment was to study and document mechanical fitments, vibration isolation, and noise suppression techniques when combining sub-systems. We mapped out signal paths and ground-loop isolation. The complete group integration documentation is available on the Fablab Dilijan Group Assignment Page.

Individual Assignment — Assembling the Go-Kart

I integrated all fabricated parts onto the CNC-welded steel frame. The process was split into mechanical packaging and power/control wiring.

1. Mechanical Packaging

  • Chassis and Wheels: Mounted the front wheel steering knuckles and the solid rear axle using pillow block bearings.
  • Driver Interface: Bolted the CNC-milled plywood seat (from Week 7) onto frame mounting brackets. Fixed the steering wheel fitted with the custom cast rubber grip handle (from Week 14).
  • Electronics Housing: Fixed the 3D-printed dashboard enclosure casing (from Week 2) containing the custom ESP32-C3 PCB (from Week 8) onto the steering column.
Integrated electrical wiring compartment with fuse box and motor controller
Electronics bay wiring harness
Completed and fully assembled Electric Go-Kart on workshop floor
Fully integrated Go-Kart assembly

2. Electrical and Power Integration

To ensure driver safety and electrical reliability, I built a modular wiring harness with dedicated high-current and low-current routing:

  • High-Current Circuit (Drivetrain): Converted a 36V Li-ion battery pack to the rear brushless DC (BLDC) motor controller. I placed a 40A Inline Fuse and a heavy-duty Emergency Stop kill-switch in series on the positive wire to quickly cut power.
  • Low-Current Circuit (Control & Signal): The ESP32-C3 dashboard board is powered via a 12V-to-5V DC-DC buck converter stepping down battery voltage. All signal wires (analog throttle, I2C lines to OLED, and status LEDs) are shielded to suppress high-frequency EMI noise from the BLDC motor.
  • Grounding: Connected all logic grounds together at a single star-ground point on the chassis to prevent ground loops.

Original Wiring Diagrams

Download the system wiring schematic diagram:

File Name Format Description Download Link
system_wiring_diagram.pdf PDF (Vector Graphic) Full electrical wiring diagram showing low-power and high-power loops. 📥 Download PDF

Have you answered these questions?

  • Made a plan for system integration for your final project?
    Yes. The layout plan detailing electrical buses, sensor routing, and motor cabling is outlined in System Architecture.
  • Documented your plan with CAD and/or sketches for system integration?
    Yes. I included CAD renderings of the dashboard enclosure packaging and wire routing channels.
  • Implemented methods of packaging?
    Yes. I fabricated a 3D-printed enclosure box with gasket channels to package the dashboard MCU and protection fuses, shown in Packaging.
  • Designed your final project to look like a finished product?
    Yes. The enclosure panel was painted, and cables were bundled in protective split looms to look like a clean, consumer-grade product.
  • Documented system integration of your final project?
    Yes. The mounting of the steering, power, and display boards onto the physical frame is documented.
  • Linked to your system integration documentation from your final project page?
    Yes. The link is placed on the final project page linking back to this system integration page.

Week 16 — Summary

This week focused on component assembly and power safety integration. Here is a summary of the accomplishments:

Structure Assembled

Assembled the CNC chassis frame, wheel bearing hubs, steering linkage knuckles, and ergonomic plywood seat.

Wiring Harness Built

Constructed a shielded low-noise wiring loom, routing sensor leads and I2C lines to the front steering panel.

Safety Loops Wired

Integrated a 40A overload fuse and a panel-mounted red Emergency Stop switch to guarantee battery isolate cut-offs.

Buck Regulated

Wired linear DC-DC buck converters to step down battery voltages, supplying clean 5.0V power to microcontrollers.