# Common Mechanisms ### Flywheel Shooter

Construction * Two counter-rotating wheels (often with compliant covers) mounted on motor shafts, spaced to pinch a round projectile. * Motors may include encoders for closed-loop speed control. Use Cases * Rapid-fire launch of small, spherical game pieces (e.g., Power Cells, foam balls). Advantages * Continuous, high-rate firing-no reload cycle time needed. * Velocity (and thus range) can be tuned on the fly by adjusting wheel speed. Disadvantages * Only handles round objects reliably-non-spherical items slip or jam. 2 * Motor speed (and shot consistency) falls off as battery voltage drops unless actively regulated by encoders. 2 ### Striker (“Impact”) Shooter

Construction * Rigid striker arm or plate driven by a geared motor or spring, which impacts the projectile to launch it. * Includes a pull-back mechanism (e.g., a torque motor with gear train) to reset the striker. Use Cases * Launching flat or irregular objects (pucks, square blocks) that cannot be gripped by wheels. Advantages * Compatible with a wide variety of shapes and sizes. 2 * Range adjustable by tuning spring tension or motor torque. 2 Disadvantages * Energy loss to friction when the object slides against a surface reduces distance. 2 * High impact loads cause wear on linkages and mounting hardware. 2 * Reset mechanism adds cycle time and mechanical complexity. 2 ### Catapult/Popper Shooter ![](https://media.tenor.com/V7SrMQFh3IwAAAAM/catapult-cat.gif) Construction * Elastic element (rubber band or spring) attached to an arm linkage, latched by a servo or pin. * Release mechanism discharges stored energy to fling the projectile. Use Cases * Single-shot loops at moderate rate for uniform, repeatable distance (e.g., tennis-ball poppers, small foam ring launchers). Advantages * Very consistent shot energy and accuracy thanks to fixed spring tension. [6](https://www.reddit.com/r/FRC/comments/bienj1/shooter_mechanisms_introduction/) * Simple control: prime once, trigger, then re-prime. Disadvantages * Fixed launch distance unless spring tension is manually adjusted between shots. [6](https://www.reddit.com/r/FRC/comments/bienj1/shooter_mechanisms_introduction/) * Mechanical linkage must absorb high forces, leading to potential fatigue and breakage. ### Linear Motion Guides

Linear Travel Guide using Stepper motor and Timing belt

**Construction:** Aluminum extrusion or steel rail profiles with rolling or plain bearings (linear slides, drawer slides, profile rails). [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Robot lifts, elevators, extendable arms, precise slide mechanisms\ Advantages * Recirculating bearings: smooth, low friction under load * Profile rails: tight tolerances, long life\ Disadvantages * Adds weight and cost * Requires precise alignment and mounting ### Arms & Elevators

**Construction:** Pivoting bars or telescoping frames driven by motors, winches, or actuators; may include cascade or continuous-loop rigging. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Scoring at various heights, reaching over obstacles * Gripper positioning and manipulator extension\ Advantages * Pivot arms: simple kinematics, compact stowage * Telescopes: extendable range, rigid at full height\ Disadvantages * Pivot: limited vertical reach without long links * Telescopes: mechanical complexity, potential binding ### Linkages

**Construction:** Rigid links connected by revolute (pin) joints, forming Four-Bar, Parallel (pantograph), Scissor, Corner, or Cross linkages. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Converting rotary motor motion into complex planar or vertical motion * Lifts, level platforms, bilateral extension\ Advantages * Four-Bar: predictable motion path, adjustable leverage * Scissor: large vertical extension in compact footprint * Pantograph: maintain parallel output motion\ Disadvantages * Multiple joints: cumulative backlash and wear * Scissor: linkage binding without precise fabrication ### Passive Intakes & Claws

**Construction:** Fixed mounting plates with compliant materials (rubber bands, foam), passive rollers or fingers. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Gripping variable-shape game pieces without active actuation * Centering objects against a backplate for further processing\ Advantages * Low complexity, minimal actuators required * Gentle on game pieces, self-centering behavior\ Disadvantages * Limited gripping force, shape dependence * No active release control ### Active Intakes

**Construction:** Powered rollers, wheels, or pneumatic fingers mounted on pivoting arms or frames. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * High-speed collection of balls, cubes, rings, or custom game pieces * Feeding objects into indexers or shooters\ Advantages * Controlled grasping and ejection, high throughput * Adjustable speed and torque for different materials\ Disadvantages * Additional motors or pneumatics add weight and draw current * Complex timing and synchronization with downstream subsystems ### Transfers & Indexers **Construction:** Belt or roller conveyors, pneumatic gates, channel guides, and staging shelves. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Sequencing multiple game pieces, buffering under shooters or scoring mechanisms * Automated stacking or batch delivery\ Advantages * Precise object positioning, continuous feeding * Scalable to multiple game-piece types\ Disadvantages * Added length and mass on the robot * Requires control logic to avoid jams ### Dead (Idle) Wheels **Construction:** Free-spinning omni or traction wheels mounted on bearings, used as load-bearing supports. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Reducing friction on non-driving corners * Stabilizing mechanisms or gantry plates\ Advantages * Simple, passive way to carry loads without consuming motor power * Minimal wear on drive motors\ Disadvantages * Adds drag if misaligned * Does not contribute to motion ### Turrets

**Construction:** Rotating subplate on thrust bearings or lazy-Susans, driven by motors or servos. [2](https://gm0.org/en/latest/docs/common-mechanisms/index.html)\ Use Cases * Aiming shooters or sensors independently of chassis orientation * Multi-directional intake or scoring without turning the robot\ Advantages * Decouples turret and chassis control, rapid targeting * Enables continuous rotation and precise angular positioning\ Disadvantages * Complex wiring management (slip rings or cable chains) * Increased mass and higher center of gravity ### Forklift Mechanisms

One of the implementations for lesser load, for higher loads a tension string is also reccomended

![](https://i.makeagif.com/media/10-17-2019/kK6oQ-.gif)![](https://sc01.alicdn.com/kf/HTB1qvb8gYwrBKNjSZPc5jXpapXa8/231818923/HTB1qvb8gYwrBKNjSZPc5jXpapXa8.gif) Above shown Screw and Belt Driven Linear Guides can also be used **Construction** * A rigid rectangular frame built from metal tubing or plates supports four drive motors with reduction gearing and a single H-bridge controller for traction and steering[6](https://blog.robotiq.com/bid/65794/magnetic-robot-end-effector-top-5-pros-and-cons). * A vertical lift assembly uses profile rails or linear slide tracks on each side to guide motion, with a rack-and-pinion driven by a DC motor to raise and lower forks or a carriage2. * Ultrasonic distance sensors mounted near the base detect shelf or object positions and trigger lift actions, all wired through a microcontroller (e.g., Arduino Uno) and soldered onto a breadboard for flexible I/O expansion2. **Use Cases** * Warehouse and warehouse-style competition challenges requiring precise fork positioning under pallets or blocks. * Educational projects demonstrating pick-and-place automation, obstacle avoidance, and sensor integration. **Advantages** * High load capacity and stable vertical motion when properly counterbalanced. * Precise height control via gear reduction and encoder feedback. * Modular design allows easy adjustment of fork width and lift height. **Disadvantages** * Heavy lift assemblies can unbalance the drive base, requiring careful weight distribution or repositioning of components2. * Increased mechanical complexity and part count raise build time and maintenance. * Rack-and-pinion systems can bind if rails are misaligned or not lubricated. ### Robotic Grippers **Mechanical Grippers** ![](https://media3.giphy.com/media/WQIN9lgizkXMgsftJ1/200w.gif?cid=6c09b952o2rbkwi508jkogf2thbv2hlplgtx2v8cdwmcdnjy\&ep=v1_gifs_search\&rid=200w.gif\&ct=g)![](https://i.pinimg.com/originals/09/50/eb/0950ebd72d7252cfca67b3a57c43279a.gif)![](https://makerworld.bblmw.com/makerworld/model/USaa761c0a98ea6b/design/2024-03-02_107745c8c8b61.gif) * Construction: Two or more rigid fingers actuated by servos, motors, or linkages; often include compliant pads for better friction[3](http://engineering.nyu.edu/mechatronics/projects/ME7836/spring2018/Arduino_mini_project/AUTONOMOUSFORKLIFTBOT/report.pdf). * Use Cases: General-purpose part handling, from small rigid game pieces to irregular objects in warehouses. * Advantages: High grip force, adaptability to varied geometries, straightforward control. * Disadvantages: Complex designs for large workpieces, increased weight, limited softness for fragile items[3](http://engineering.nyu.edu/mechatronics/projects/ME7836/spring2018/Arduino_mini_project/AUTONOMOUSFORKLIFTBOT/report.pdf). **Vacuum Grippers**

* Construction: Suction cups linked to a vacuum pump or venturi generator, often with integrated pressure sensors[4](https://www.hvrmagnet.com/blog/robotic-grippers-advantages-and-disadvantages/). * Use Cases: Handling flat, smooth panels, sheet goods, glass, and light game elements. * Advantages: Simple design, fast pick-and-place cycles, low profile for tight spaces. * Disadvantages: Only works on non-porous surfaces; rubber cups wear and require frequent replacement[3](http://engineering.nyu.edu/mechatronics/projects/ME7836/spring2018/Arduino_mini_project/AUTONOMOUSFORKLIFTBOT/report.pdf). **Magnetic Grippers**

* Construction: Electromagnets, permanent magnets, or electro-permanent magnets embedded in a flat contact pad[3](http://engineering.nyu.edu/mechatronics/projects/ME7836/spring2018/Arduino_mini_project/AUTONOMOUSFORKLIFTBOT/report.pdf)[5](https://www.robots.com/articles/grippers-for-robots). * Use Cases: Lifting ferrous parts, sheet metal handling, assembly tasks with metallic game pieces. * Advantages: Single contact surface, rapid gripping, minimal structural components, energy-efficient (permanent/electro-permanent)[3](http://engineering.nyu.edu/mechatronics/projects/ME7836/spring2018/Arduino_mini_project/AUTONOMOUSFORKLIFTBOT/report.pdf)[5](https://www.robots.com/articles/grippers-for-robots). * Disadvantages: Limited to ferrous materials, reduced holding force if surfaces are oily or covered in debris, parts may retain magnetism[3](http://engineering.nyu.edu/mechatronics/projects/ME7836/spring2018/Arduino_mini_project/AUTONOMOUSFORKLIFTBOT/report.pdf)[5](https://www.robots.com/articles/grippers-for-robots). **Pneumatic Grippers** ![](https://i.makeagif.com/media/10-31-2021/FXU2PU.gif)![](https://i.makeagif.com/media/3-25-2016/BR1KiP.gif)![](https://d2t1xqejof9utc.cloudfront.net/screenshots/pics/3dc2efe423c1f55732962568aeb8d35a/large.gif)![](https://media1.giphy.com/media/Kz3x7cl4SN1zSeWPSm/giphy.gif?cid=6c09b952o2rbkwi508jkogf2thbv2hlplgtx2v8cdwmcdnjy\&ep=v1_gifs_search\&rid=giphy.gif\&ct=g) * Construction: Parallel or angular jaw fingers driven by air cylinders, with flow control valves for speed and force tuning[4](https://www.hvrmagnet.com/blog/robotic-grippers-advantages-and-disadvantages/). * Use Cases: High-speed pick-and-place, automated packaging, fluid-tight sealing in assembly. * Advantages: High force-to-weight ratio, fast actuation, built-in compliance. * Disadvantages: Requires compressed air infrastructure, noisy operation, potential air leaks. **Servo-Electric Grippers** ![](https://d2t1xqejof9utc.cloudfront.net/screenshots/pics/7203e21784acae125abf0f5c62fb2cb9/large.gif)![](https://cdn.shopifycdn.net/s/files/1/0084/2799/5187/files/6_4d35b36a-1fb3-44b3-9e53-46cf1ddeb343.gif?v=1647564810)![](https://media.printables.com/media/prints/403482/images/3358009_e15a5169-52c2-4126-bcc0-fe2914e47cdf/thumbs/inside/1280x960/jpg/18db8080b42e32ebe3a4fd084945e65c.webp) * Construction: Brushless or stepper motors with gearboxes driving finger linkages, often with integrated position and force sensors[4](https://www.hvrmagnet.com/blog/robotic-grippers-advantages-and-disadvantages/). * Use Cases: Precision handling in electronics assembly, variable-force tasks in competition robots. * Advantages: Precise position and force control, easy integration with digital controllers, low maintenance. * Disadvantages: Higher cost, more complex control algorithms, potential heat generation in continuous use. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://panav.gitbook.io/robotics-handbook/common-mechanisms.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.