Embedded Files
Project Goal:
Project Goal:
Design and integrate a 4-degree-of-freedom robotic arm for an autonomous exploration rover in the University Rover Challenge (URC), enabling reliable sample collection, tool handling, and fine manipulation with a focus on stiffness, controllability, and reliability.
My role:
My role:
Robotics Co-lead
Lead end-to-end mechanical design, CAD, manufacturing, and testing of the robotic arm within a 10-member team.
Coordinate technical efforts across structural analysis (FEA), manufacturing partners, and subteams, guiding design reviews, milestones, and feedback integration.
Technical Skills: Non-technical Skills:
Technical Skills: Non-technical Skills:
CAD (Onshape) Technical Leadership
Mechanical Design & Integration Project Planning & Coordination
Structural Analysis (FEA) Cross-Team Communication
Prototyping & Manufacturing Mentorship & Training
Specifications
Specifications
Degrees of freedom: 4
Maximum reach: 3 ft
Total arm mass: 10.7 kg
Payload: 5 kg
Primary Material: 6061 aluminums
End effector type: Multi-purpose manipulator
Control mode: Teleoperated
Results & Insights:
Results & Insights:
Finalized and fully toleranced robotic arm CAD design.
Structurally validated the system through finite element analysis (FEA).
Incorporated design feedback from the chief engineer, industry systems engineers, and URC judges.
Mechanical Design:
Mechanical Design:
Manipulator (End Effector)
Manipulator (End Effector)
The manipulator is designed for URC tasks including sample collection, tool handling, and fine motor actions such as typing. The design emphasizes precise control, repeatable jaw motion, and compliant gripping to securely interact with both rigid tools and irregular objects, while remaining modular for future iteration. A central circular interface allows the attachment of a dedicated extension for precise and repeatable typing tasks (as shown by the orange drawing).
Key Component Specifics:
Key Component Specifics:
goBILDA servo motor
Warm gear system
Linkage (Arm Structure)
Linkage (Arm Structure)
The linkage uses a 4-DOF layout to provide ~600 mm reach for URC tasks while keeping the primary joints belt-driven for smooth, repeatable teleoperated motion. The structure is built from MAXTube 1×1 members to balance stiffness and weight, with torque transmitted through RT25 belt stages using REV pulleys, minimizing backlash and helping maintain stable load paths during sampling and tool manipulation.
Key Component Specifics:
Key Component Specifics:
Structure: MAXTube 1×1 (REV-21-2160)
Actuation: 12 V brushless DC motor (NEO)
Transmission: RT25 pulleys (REV-21-2205 16T, REV-25-2236 32T) + RT25 belts (REV-21-4032, REV-21-4040)
Static FEA for von Mises stress with deformation at full extension
Base (Rotation & Mounting)
Base (Rotation & Mounting)
The base provides controlled rotation of the arm while efficiently transferring loads into the rover chassis during manipulation tasks. Rotation is driven by a brushless DC motor and supported by a turntable bearing to handle axial and radial loads, ensuring smooth motion and stable torque transmission. The structure is designed to provide a stiff, reliable interface between the arm and rover chassis.
Key Component Specifics:
Key Component Specifics:
Actuation: 12 V brushless DC motor (NEO)
Bearing: Maintenance-free turntable bearing (160 mm OD)
Structure: 6061 aluminum plates (1/4″ and 1/2″ thick)
Mounting: Custom steel angle brackets for upright support
Manufacturing & Assembly:
Manufacturing & Assembly:
The robotic arm was fabricated using a combination of waterjet cutting, CNC machining, and in-house assembly to ensure structural integrity and precise subsystem integration.
Processes include:
Processes include:
Waterjet cutting of base plates
CNC machining, lathe work, and milling of custom brackets
Cutting of aluminum extrusions for linkage members
In-house assembly and iterative fit-up for alignment and integration
The machine shop training of safely extruding the linkage members
Testing:
Testing:
Performance is evaluated through systematic testing across multiple configurations to assess grasp reliability, compliance, and repeatability under varying conditions.
Testing will evaluate task-level performance aligned with University Rover Challenge manipulation requirements.
Key testing steps include:
Key testing steps include:
Sample collection and placement
Tool handling and switch/knob actuation
Controllability, repeatability, and structural stability
Successful task completion under teleoperated conditions
Future Plan:
Future Plan:
The arm is currently being assembled and the components will soon be manufactured. Upcoming work includes task-based testing of 3D-printed prototypes, focusing on challenge operations such as typing and sample collection and placement.
Page updated
Google Sites
Report abuse