This week focuses on defining the scope, requirements, costs, and execution planning for the final project. It establishes the foundational framework for building, testing, and evaluating the prototype.
Final Project Concept & Scope
Q1. What does it do?
The project is an automated mobile robotic system consisting of a tracked mobile platform (CarTrack) integrated with a specialized, active ball-collector mechanism. The system is designed to autonomously or remotely navigate open environments, locate small sports or industrial balls, and efficiently collect them into an onboard storage bay. By utilizing continuous rubber tracks, the platform ensures optimal traction and stability across uneven terrain while the motorized roller sweeps targets seamlessly into the chassis.
Q2. Who's done what beforehand?
This project leverages industrial automated guided vehicle (AGV) architectures and automated sports cleanup machinery. Key reference structures include:
- Tennibot & Open-Source Field Rovers: Proven implementations demonstrating the effectiveness of autonomous tracking loops paired with mechanical rotating sweepers to harvest tennis and golf balls on court surfaces.
- Custom Tracked Open Hardware Chassis: Precedents utilizing high-torque planetary DC gear motors and continuous belt tracks to overcome rugged outdoor terrain limitations common to standard wheeled rovers.
These commercial and community benchmarks informed my custom-designed chassis footprint, electronics modularity, and high-efficiency collector mechanism optimization.
Q3. What did you design?
The entire assembly consists of entirely custom-engineered architectural layers spanning physical, mechanical, and electronic domains:
- Mechanical System & Chassis: A modular, parametric tracked chassis structure incorporating customized sprockets, idler wheels, and an integrated motorized front-roller intake subsystem for ball retrieval.
- Embedded Control Board: A custom-fabricated PCB designed within KiCad, engineered to support dual high-current motor drivers for the drive tracks alongside a dedicated servo/DC driver for the collection accessory.
- System Layout: A durable, structured carrier frame optimized to isolate sensitive control electronics from the physical collection container, calibrated within a portable footprint of approximately 30 cm x 22 cm.
Bill of Materials (BOM)
A detailed breakdown of all raw materials, active electronic components, and structural hardware allocation:
| Component | Supplier / Source | Approx. Cost (MXN) | Operational Notes |
|---|---|---|---|
| Purchased Components | |||
| Continuous Rubber Tracks & Sprockets (Set) | MercadoLibre | $380.00 | High-traction locomotion belts for terrain traversal. |
| High-Torque DC Gear Motors (12V, 2 pcs) | MercadoLibre | $240.00 | Primary propulsion drivetrain units for the tracked system. |
| MG995 High-Torque Servo Motor | MercadoLibre | $89.00 | Actuation unit for positioning the intake collector arm. |
| OLED Display 128x32 I2C | MercadoLibre | $58.00 | Real-time telemetry, system diagnostic, and state monitoring. |
| AMS1117-5V Regulators (5 pcs) | MercadoLibre | $25.00 | Voltage regulation rail for logic and accessory signaling. |
| L298N / Dual H-Bridge Motor Driver IC | MercadoLibre | $45.00 | High-current direction and speed drive controller for tracks. |
| Female Header 40 pins (5 pcs) | MercadoLibre | $20.00 | Modular sockets for controller daughterboard interfacing. |
| Phenolic Copper Board 10x15 cm | Steren | $24.00 | Substrate stock for milling custom control circuitry. |
| Structural Hardware (M3 Screws/Nut Pack) | Steren | $35.00 | Rigid structural fastening of chassis frames and linkages. |
| Provided by FabLab Ibero Puebla (In-Kind) | |||
| Seeed Studio Seeeduino XIAO ESP32-C3 | FabLab Inventory | $0.00 | Central microcontroller core for processing logic and control. |
| PLA / PETG Filament Stock (Chassis Parts) | FabLab Inventory | $0.00 | 3D printed structural frames, wheels, and collector assembly. |
| SMD Capacitors, Resistors & Buttons | FabLab Inventory | $0.00 | Basic debouncing, passive decoupling, and physical resets. |
Total Project Financial Footprint: $916.00 MXN (Out-of-pocket procurement budget) / FabLab infrastructure allocation utilized for rapid additive fabrication and component stocks.
Project Development & Integration
Q5. What parts and systems have been made?
To date, development milestones have achieved critical verification status across all system boundaries: the main custom-milled ESP32-C3 control board has been fully populated, reflowed, and verified for logic safety. Robust structural prints of the chassis side-plates, internal structural mounts, and the primary collector roller mechanism have been generated through additive FDM manufacturing. Total platform integration currently sits at roughly 75% complete, awaiting final mechanical track synchronization.
Q6. What processes were used?
Aligning with core digital fabrication paradigms, this project unifies multiple technical manufacturing processes:
- Additive & Subtractive Manufacturing: Durable FDM engineering printing (rigid PETG/PLA configurations) for the high-impact mechanical collector chassis, coupled with precision desktop CNC milling of the custom motor control circuitry layer.
- Electronic & Firmware Design: Parametric schematic layout and trace routing engineered within KiCad, paired with embedded C++ tracking logic for hardware-software synchronization.
Q7. What worked? What didn't?
Worked: The custom-milled control board handled the power requirements of the driving tracks perfectly during initial bench testing. 3D-printed tolerances on the driving sprockets allowed the track belts to interlock cleanly without slipping.
Challenges: Getting the sweep speed of the ball-collector roller precisely right has been tricky. If it spins too slowly, balls are pushed away, but if it spins too quickly, they jam against the entry ramp. Fine-tuning the mechanical collection angle is required to ensure a smooth transition into the storage bay.
Q8. How will it be evaluated?
The system will be validated against explicit performance metrics: smooth locomotion and turning stability of the tracked platform without belt displacement under load, ball gathering efficiency rates across flat surfaces, response latency from remote control overrides, and proper electrical isolation of inductive motor spikes across the custom PCB logic lines.
Execution Schedule
Critical phase roadmap leading up to final system submission deadlines:
- Phase 1 (Current Week): Finalize physical assembly of the ball-collector intake ramp. Calibrate motor coupling tolerances and secure the continuous tracks onto the primary chassis.
- Phase 2 (Next Week): Complete electronic wiring harness paths. Integrate the collector roller motor code with the main drive control loop, and calibrate intake sweeping speeds.
- Phase 3 (Final Week): Conduct operational field trials for collection reliability, wrap up the online portfolio project documentation, and compile the final overview video presentation.