Hardware Projects

Project Overview:

In response to limited engineering resources at Attabotics, I took the initiative to design and develop LED-responsive totes to enhance tradeshow visibility for Attabotics in my own time. These totes were required to dynamically react to their environment and operate safely for the entire 3-day event without recharging.

Project Requirements:

• Fully autonomous operation for 3+ days without recharging

• Safe, reliable battery technology suitable for public environments

• Visual responsiveness to robot interactions, without direct wired interfaces

• Scalable, easily assembled design for a batch of 10+ units

• Integration of both electronic and mechanical design considerations

Key Contributions & Outcomes:

• Selected LiFePO4 batteries for optimal safety and power density

• Designed and completed the entire PCB schematic in Altium within a day, using off-the-shelf components; included voltage monitoring and robust Molex connectors for assembly and maintenance

• Developed the 3D-printed enclosure in Fusion 360 to facilitate easy assembly and secure integration of electronics

• Implemented a Time-of-Flight (ToF) sensor system to detect tote state and trigger LED responses without relying on wireless protocols

• Collaborated with a colleague who developed a state machine to process ToF sensor data and control LED states

• Performed power budgeting to ensure the totes operated for the full duration of the show

• Completed design, assembly, and testing of proof-of-concept prototypes in under 2 days with assistance from colleagues

• All deployed totes functioned flawlessly, achieving 95% uptime and significantly improving booth visibility during the tradeshow

Skills Demonstrated:

PCB design, rapid prototyping, mechanical design, power systems, system integration, problem-solving under tight deadlines, and cross-disciplinary collaboration.

Project Overview:

As a Director for the Senior Design category at the Canadian Engineering Competition (CEC) 2024, I helped organize a national mechatronics challenge where student teams had to build robots from provided kits within 8 hours. A key requirement was to provide all teams with a reliable, low-cost remote control system to ensure fairness across the competition.

Project Requirements:

• Cost-effective remote control solution within a strict $10 per-unit budget

• Simple, reliable hardware that teams could integrate quickly during the competition

• Wireless control using familiar devices (PS3/PS4 controllers or smartphones)

• Standardized module to ensure consistent technical expectations for all teams nationwide

• Design-for-manufacturing approach to build 8 complete modules within budget

Key Contributions & Outcomes:

• Designed a custom Remote Control Module based on the ESP32 WROOM32E, providing Bluetooth and BLE connectivity

• Developed a straightforward interface where button or joystick inputs map directly to GPIO pins, simplifying integration for teams

• Included hardware features such as:

  • Integrated voltage regulator for stable operation

  • USB-UART bridge for easy programming via USB-C

  • ESD protection and GPIO protection for robustness

• Custom 3D-printed enclosure to protect the electronics

• Applied design-for-manufacturing principles:

  • Optimized BOM to meet cost targets

  • Careful part selection and trade-offs to balance performance and budget

  • Excluded non-essential features like DAC outputs and indicator LEDs to avoid complexity

• Iterated through three design revisions before final production

• Successfully produced and assembled 8 fully functional modules

• All modules worked flawlessly during the competition, with no failures or disconnections reported

• First instance of custom hardware being introduced to the CEC Senior Design challenge

Skills Demonstrated:

Hardware design, system integration, budget management, design-for-manufacturing, rapid prototyping, and supporting national-level technical competitions.

For my technical team AC Robotics, I was tasked with creating a PoC integrated motor controller solution for the initial prototype of our robot dog project: XP1 CANIS. We were initially having issues controlling several motors with encoders over one MCU, so we wanted to experiment with having one integrated controller per motor, and then having a central processor control each individual integrated controller over a communication bus such as RS485 or CANBUS. 

For this PoC, I decided to use the RP2040 due to the chip shortage at the time for ATmega, and STM controllers, as well for the price since we would need a board per motor. This was a challenging project, fitting and routing the PCB within mechanical constraints and space, while also being able to deliver the power requirements and communication requirements for this integrated controller.

This project incorporated the appropriate voltage regulators for the ICs, a small motor controller IC with integrated FETs, a RS485 Transceiver, and the corresponding headers to connect the various components together.

I did make a mistake where I did not do the USB traces properly, so I had issues where the pads and traces would consistently rip off the board, hence the electrical tape connecting the USB! Another alternative was chosen and we are currently deciding on whether to get an after market solution or rethink the development of a better integrated controller to have precise control and speed for applications such as a robot dog.

With the STM32 as a popular industry choice for microcontroller, I wanted to get some experience designing reference boards for STM32 chips. I decided it would be fun to design a "remote controller" board for robot interfacing applications or general controller design for future projects. I decided it would also be fun to incorporate the joysticks from the popular Joycons on the Nintendo switch.

This board is designed with an MCU from the STM32 F0 series which is the lower cost and lower power M0 ARM Cortex controllers. I experimented with placing the IC at 45 degrees to observe how it would change/simplify routing as I saw an experimental video regarding this topic. This board has the appropriate voltage regulation for the various peripherals and controllers, as well as an USB-Serial converter to be programmed directly over Serial without the use of an ST-LINK. However, it does have breakouts for SWD, an nRF24 wireless transceiver, and general I/O breakout.

Through this project, I was initially going to use an Arduino core to be able to program this board with the Arduino IDE. However, this project led me to look into programming the STM32 using HAL and led me into learning more how to program the STM32 chipset using HAL as well as through native C/C++ instead of an Arduino core.

I noticed that many "basic two drive robot" starter kits consisted of typically an Arduino and L298N motor controllers and wondered why there wasn't a board that integrated all of the several components onto one board to save on space and cost.

As a personal project, I decided to create the custom hardware with the ATmega328p integrated with 2 L298N drivers and the additional peripherals to support a general purpose robot board that could be used to create fast robots or for educational/STEM purposes. This board can support up to 4 motors with quadrature encoders. Since the L298N is an older driver, a multiplexer is used to control the directionality of the motors due to the limited IO and peripheral capability of the ATmega328p.

This board is also equipped with breakouts for a nRF24 wireless breakout board, I2C OLED screen, and WS2812b LED strips, and a USB-Serial converter. It has the appropriate regulators to feed the 5V, 3.3V and VCC power lanes and can be powered from one VCC input. 

Through this project, I discovered various limitations of handling 4 motor control with quadrature encoders on a microcontroller from 2008 in which the clockspeed, (8MHz), hardware peripherals, and overall capabilities are limited.

PCB Schematic

Soldered PCB