Identification

Mechanical architecture

Four major subsystems:

• Drivetrain: 4-wheel, two motors (Ports 1 & 10), 4″ wheels — one omni and one regular per side. Chain-driven (65 high-strength chain links, step 6).
• Vertical mast: Two stacked C-Channel 1×5×1×25 sections forming a vertical lift tower (steps 17, 26).
• Articulated arm: Shoulder joint at base of mast (Port 7), elbow joint mid-mast (Port 6), connected by gear trains. Forearm slides on a linear slide track (steps 23–25). Driven by 60T high-strength gears.
• Claw + wrist assembly: Wrist motor (Port 8) at the end of the forearm rotates a 60T gear (steps 38, 42), which drives the claw mounting plate. Claw motor (Port 9) operates the gripper itself.

What makes it stand out from the basic Clawbot

The basic V5 Clawbot has 4 motors: 2 drive + 1 arm + 1 claw. Total degrees of freedom (DOF): 2 (lift up/down, claw open/close).

The Super Clawbot has 6 motors: 2 drive + 4 arm. Total DOF: 4 (shoulder, elbow, wrist, claw). That's 2× the manipulator capability of the basic Clawbot — meaningfully closer to a competition-style robot.

Sensors included

• 3× Line Tracker (steps 15) — for line-following demos
• 3× Bumper / Limit Switch — mechanical end stops
• 1× Ultrasonic Range Finder (step 46) — mounted at the claw for object detection
• 2× Optical Shaft Encoder (step 28) — positional feedback on the arm joints
• 2× Integrated Encoder Module (IEM) on drive motors

This is a thoroughly sensored robot for its era — sensor-rich teaching value was the design intent.

Why this design is interesting in 2026

• The wrist is rare in modern V5 builds. Most V5 teams use four-bars or DR4Bs, both of which lock the gripper orientation to the arm. A wrist gives independent control — useful for cup orientation in Override.
• Articulated arms are underrepresented in V5RC. Easier-to-build linkage lifts dominate. An articulated arm done well can outperform them in tasks that need 3D reach.
• The mechanical engineering is solid. Sealed gear trains, rigid mast, proper chain runs, sensor mounting points — this isn't a thrown-together design.
• The electronics are 100% obsolete. Cortex, Motor 393, MC29s — none of it is V5RC-legal. The conversion is non-optional if you want to compete.

That mismatch — great mechanical design, dead electronics — is exactly what makes this a good conversion candidate.

Drop-in replacements (no structural change)

Structural changes that matter

1. Motor mounting — biggest change

Motor 393 has a square mounting face with 4 perimeter holes. V5 Smart Motor has a different bolt pattern with 5 hole points. They are not interchangeable in the same hole pattern.

Affected mounts:

• Drive motor mounts (steps 3, 8) — need new screw locations or V5 motor mount adapters
• Shoulder + elbow motor mounts on the mast (step 17) — the most affected. Two 393s mounted close together; V5 motors are physically larger and may need spacing apart
• Wrist motor mount (step 41) — mounts to a 5x5 plate; new hole pattern
• Claw motor mount (step 1) — pre-assembled in the claw kit, easier swap

Practical fix: Use VEX V5 Motor Mount kits (available separately). They bolt to the existing 5-hole grid but add ~3/8″ of stack height. Plan that 3/8″ in CAD.

2. V5 Brain mounting — needs new location

The Cortex is a flat rectangular box mounted on its side near the chassis center (step 34). The V5 Brain is larger (~5.5″ × 4″) with a touchscreen on top that must remain visible and reachable during pre-match setup.

The original Cortex location won't work directly. New location options:

• Top of chassis, behind the arm — touchscreen visible from outside the robot. Best for pre-match access.
• Front of chassis, screen forward — visible from the driver station. Good for match feedback but wastes front real estate.
• Side of chassis — accessible but adds width and may interfere with wheels.

Build a dedicated mounting plate on top of the chassis frame. Use a 5x5 plate with cutouts for the cable strain-relief.

3. Battery bay — resize

EDR battery is small (7.2V NiMH). V5 battery is ~4.5″ × 3″ × 1.5″, much larger and ~1 lb heavier. The original battery strap mount (step 52) is sized for the EDR battery.

Fix: Enlarge or relocate the battery bay. Best practice: mount V5 battery low and central for low CG — benefits drive stability and pushing power.

4. Cable routing — entirely new approach

EDR has many separate wires: power (red/black), signal, encoder, sensor, all running to different ports. The wiring diagram on PDF page 30 shows ~15 separate cables.

V5 uses one Smart Cable per motor or sensor — power + signal + data in one cable. Drastically fewer cables but each is thicker and stiffer.

Implications:

• Existing zip-tie cable management routing needs rework
• Strain relief at the brain matters — V5 ports can be damaged by sideways cable pull
• Cable runs through articulated joints (shoulder, elbow, wrist) need careful planning

5. Drivetrain upgrade — 4WD → 6WD center-drop

Original is 4WD with 4″ wheels (step 4). For Override, the recommended drivetrain is 6WD center-drop with 3.25″ wheels (4 omni corners + 2 traction center, dropped 1/16″).

While you're rebuilding, build it as 6WD. Adding the 2 center wheels later is harder than building them in. See wheel-placement-guide for the detailed math.

Optional structural improvements

• Strengthen the shoulder mount. Original uses a single C-channel mast; under V5 motor torque + arm + game piece weight, this can flex. Three options, lightest to heaviest: internal aluminum spacer reinforcement (Spartan's default — ~1.1× weight, 3–5× torsional stiffness), doubled C-channel back-to-back (2.0× weight, ~6× stiffness), or a triangular brace.
• Add cable management. VEX cable clips and zip ties along the mast for clean Smart Cable routing. Note: 3D-printed cable guides are not legal on the competition robot under R25 — the GDC banned 3D printed parts entirely starting in 2025-26.
• Replace 4″ wheels with 3.25″. Better acceleration, more headroom in the 18″ box, more pushing power. Override default.
• Add corner gussets to the chassis. The added weight of the V5 components (~1.5–2 lb) puts more stress on the chassis joints.

Cartridge selection logic

V5 motors come with three swappable cartridges:

For this robot:

• Drive motors: Blue, geared down via 36:60 (or similar). Top speed ~5 ft/s, torque sufficient for pushing. See override-drivetrain-config.
• Shoulder + elbow: Red. The arm is heavy; gravity-hold needs torque, not speed. Slower but more reliable.
• Wrist: Green. Cup orientation flips don't need the highest torque; faster response time matters for cycle speed.
• Claw: Red. Grip strength is the priority. A red claw won't crush a cup but holds firmly.

Wattage management

V5RC caps total robot motor power at 88W (R10a) and drivetrain power at 55W (R11a). There is no motor-count limit — only wattage. With 4×11W drive (44W) + 4×11W arm (44W), the V5 Super Clawbot hits exactly 88W. Real-world current draw varies:

• Drive motors only pull peak current during acceleration and pushing
• Arm motors pull while moving or holding against gravity, idle when stable
• Wrist and claw motors are very low duty cycle

Standard practice in V5RC. 88W exactly is the typical configuration for top teams.

Per-joint range estimates

Reach envelope

The reachable workspace of the gripper is approximately a hemisphere centered on the shoulder joint, with cutouts for:

• Directly behind the mast (where the arm can't fold back through itself)
• Below the chassis (ground clearance)
• Extreme angles where shoulder + elbow would collide

For Override field elements, this means the gripper can reach:

• Floor pickup: Yes — elbow extended down, wrist rotated to align claw with pin/cup orientation.
• Short goal scoring: Yes, easily.
• Tall center neutral goal: Possibly — depends on arm segment lengths. Verify in CAD.
• Toggle face: Yes — arm extended forward at chassis-perimeter height.
• Cup orientation flip: Yes — this is the wrist's killer feature.

The cup orientation problem — why the wrist matters

Override cups have a transparent half and an opaque half. A pin scores in your alliance color only if the transparent half is over the pin. If the cup lands opaque-side up, the pin underneath is hidden — it scores as the cup's color, not the pin's.

This means cup orientation matters during scoring. Without a wrist:

• If you pick up a cup wrong-side-up, you have to drop it and re-grip to flip it
• That costs you 2–4 seconds per misalignment cycle
• Across a match, this can cost 20–40 seconds of lost cycle time

With a wrist:

• Pick up the cup in whatever orientation it's in
• Rotate the wrist 180° mid-cycle if it's wrong-side-up
• Score normally — no drop, no re-grip, no time loss

This is the most concrete competitive advantage of the articulated-with-wrist design. Quantifiable in seconds saved per match.

Range-of-motion validation

Before committing to the build, validate the geometry:

1. CAD it in Onshape. Use mate constraints to model each joint with its mechanical stops.
2. Sweep through each joint's range. Check for collisions, cable interference, and unreachable poses.
3. Plot the reach envelope. Identify the maximum height (for tall goal), maximum forward reach (for toggle setting), and the floor-pickup pose.
4. Verify against Override field measurements. See override-intake-geometry for game element heights and goal positions.

Build a physical mockup

If the team has access to an actual EDR Super Clawbot, measure the real ranges with a protractor before trusting the CAD. The CAD will show theoretical maximum range; the real robot has friction, cable drag, and slop that reduce the usable range.

If no EDR robot is available, consider building a prototype arm with V5 motors and structural metal before committing the full robot. Half-day exercise that catches geometry issues early.

Strengths in Override

• Cup orientation correction via wrist. The killer feature for a stacking game with orientation requirements. Saves 20–40 sec per match in dropped/re-gripped cycles.
• Multi-height reach. Can score on short goals, tall center goal, and reach toggles — all from the same robot. A four-bar locks you into one or two heights.
• Floor pickup flexibility. Articulated arm can pick up pins/cups from any orientation. Four-bars need pieces in a specific position.
• Toggle setting. Arm reaches forward at chassis-perimeter height to set toggles — same mechanism, different pose.
• Defensive option. Arm can be raised high to interfere with opponent cycles, or extended forward to push.

Weaknesses in Override

• Cycle speed. Articulated arms are slower per cycle than four-bars. Each joint moves independently; coordination takes time. For pure volume cycling, four-bars win.
• Driver complexity. Operating shoulder + elbow + wrist + claw simultaneously is hard. Drivers need months of practice.
• Reliability under match pressure. 4 articulated joints = 4 things that can fail. Four-bars have ~1 failure mode (motor or chain). Statistically, articulated arms break more often.
• Build complexity. 52 build steps in the original PDF. Easily 3× the build time of a four-bar.
• No wattage budget for endgame mechanisms in the base V5 conversion. 4+4 motors at 88W leaves nothing for descoring, secondary intake, or motorized endgame in this configuration. Mitigation: swap to half-motors at low-load joints (see V2 variant) to free 11W for an extra mechanism.

Archetype fit

vs. four-bar V1

If the team currently runs a four-bar V1 and is considering this as V2, the comparison is:

Honest read: The articulated arm is a real upgrade for archetype-fit reasons (Toggle Controller / Solo Scorer), but it costs significantly more in build time, driver training, and reliability. If V1 is reliable and the team archetype is Cycle Specialist, stick with V1. If V1 has reliability issues OR the archetype is Toggle Controller / Solo Scorer, V2 is genuinely better.

The middle path: drop the wrist

If the team wants the multi-height reach but doesn't want to commit to wrist complexity, build a 3-DOF version: shoulder + elbow + claw, no wrist. That's 3 manipulator motors instead of 4, leaving 5 motors for drivetrain (4 used) plus 1 spare for an endgame mechanism or secondary feature.

This is the recommended V2 for most middle school teams. Captures most of the upside (3D reach) without the wrist's control burden. The wrist becomes a V3 upgrade if V2 proves the architecture.

Phase 0: CAD validation (1–2 weeks)

1. Model the V5 conversion in Onshape with all V5 components correctly sized
2. Verify motor mount clearances on shoulder, elbow, wrist mounts
3. Plot full range of motion for each joint — check for collisions
4. Plot the reach envelope — verify it covers Override field heights
5. Plan cable routing through every joint at full range
6. Verify weight balance (with V5 battery + brain placement)

Phase 1: Drivetrain (1–2 weeks)

1. Build 6WD center-drop chassis with 3.25″ wheels
2. 4 V5 motors, blue cartridge, geared 36:60
3. Verify the 1/16″ drop with the rock test
4. Mount V5 Brain on top of chassis
5. Mount V5 battery low and central
6. Test push force against another robot of similar weight
7. Tune drive PID via pid-diagnostics

Phase 2: Mast and shoulder (1 week)

1. Build the vertical mast (use internal aluminum spacer reinforcement at shoulder mount, mid-span, and top)
2. Mount shoulder motor (red cartridge)
3. Build shoulder gear train (60T high-strength gear from PDF step 20, adjust for V5 motor mount)
4. Test shoulder range with no arm attached — verify clearances
5. Add limit switches if range needs hard stops

Phase 3: Elbow + forearm (1–2 weeks)

1. Mount elbow motor on mast
2. Build elbow gear train (steps 21–22 in PDF, adjust for V5)
3. Build linear slide track forearm (steps 23–25)
4. Test elbow range with weight at end of forearm
5. Verify shoulder + elbow combined range covers floor and tall goal

Phase 4: Wrist + claw (1 week)

1. Mount wrist motor at end of forearm
2. Build wrist gear train (60T + 12T pinion, steps 38, 42)
3. Mount V5 Claw Kit v2 to wrist output
4. Test wrist range — verify cable doesn't bind at full rotation
5. Test claw grip with a cup — verify grip strength is right (no crushing, no slipping)

Phase 5: Sensors + cable management (3–5 days)

1. Add V5 Distance Sensor at claw (replaces Ultrasonic Range Finder)
2. Add bumper switches at limits if needed
3. Add an inertial sensor (IMU) on the chassis for autonomous
4. Route Smart Cables through the arm with strain relief at each joint
5. Verify cables don't bind at any joint position

Phase 6: Code + driver practice (ongoing)

1. Write basic teleop — tank drive + arm controls
2. Add position presets for shoulder + elbow (preset poses for floor pickup, short goal, tall goal)
3. Add wrist auto-flip (one button = rotate wrist 180°)
4. Tune arm PID to hold positions reliably against gravity
5. Driver practice — minimum 4 weeks before first competition
6. Build autonomous routines incrementally (start with 1-pin auton, build up)

Total timeline

~8–10 weeks from start to a competition-ready V2. Faster if you cut Phase 0 (don't recommended) or skip the wrist (Phase 4 partial). Slower if you encounter cable routing issues (likely on first build).

Chassis fit (3 checks)

• ☐ Robot fits in 18″ × 18″ × 18″ start box with arm in stowed position
• ☐ Robot weight is under 25 lb (V5RC SC4)
• ☐ Battery is removable without disassembling the arm

Motor clearance (3 checks)

• ☐ Each V5 motor has at least 1/8″ clearance to nearest metal in any joint position
• ☐ Smart Cable connector has clear access on all 8 motors
• ☐ Motor cartridges are removable for service without full disassembly

Joint range (4 checks)

• ☐ Shoulder reaches highest expected position (tall goal scoring)
• ☐ Elbow + shoulder combined reaches floor for pickup
• ☐ Wrist completes 180° rotation without cable bind
• ☐ No joint position causes collision with another joint or the chassis

Cable routing (3 checks)

• ☐ Smart Cables routed through joints without exceeding minimum bend radius
• ☐ Cable strain relief at each joint — cables can't pull on connectors
• ☐ Total cable length is sufficient for full range of motion (add ~20% slack)

Weight balance (2 checks)

• ☐ Center of gravity is forward of the rear wheels (no tipping back when arm is raised)
• ☐ CoG is low and central for drive stability

How to validate in Onshape

1. Build all 8 motors as parts with correct mass and bolt patterns
2. Mate each joint with constraints matching real range (shoulder revolute joint with 90° limit, elbow with 120°, etc.)
3. Add the V5 Brain and battery as parts with correct dimensions and mass
4. Use the Onshape mass properties tool to verify total weight and CoG
5. Animate the arm through full range — record where collisions occur
6. Generate a 2D drawing of the start-box compliance check (top, front, side views)

If CAD reveals problems

Common issues and fixes:

• Reach is short of tall goal: lengthen forearm by adding standoffs, or tilt the mast forward
• Cable binds at wrist 180°: reduce wrist range to 150°, or add a cable spool
• Robot tips back when arm raised: move battery forward, or shorten arm, or add front ballast
• Doesn't fit in 18″ box: redesign the arm-stow position, or shrink the chassis footprint
• Motors collide at shoulder: use V5 motor mount adapters to space them apart

Final pre-build sign-off

Before any team member starts cutting metal, confirm with Coach:

• ☐ CAD model is complete and reviewed
• ☐ All 15 checks above pass
• ☐ Build order is documented (Phase 0–6 in Section 7)
• ☐ Engineering notebook entry exists explaining why this V2 design was chosen over V1
• ☐ Team archetype from override-scoring matches the design (Toggle Controller or Solo Scorer)

Companion guides