Name: 3d support types for stability and motion
Uploaded: 2023-09-22T11:49:23.000Z
Duration: 1 min 27 s
Channel: JoVE

A variety of supports are employed in mechanical engineering based on their application.&#160; These support reactions in a three-dimensional force system prevent the system from translating and rotating.
Consider a robotic arm lifting a weight. Here, joint A is a ball and socket joint. The arm is free to rotate about any axis as there is no moment to restrict the rotation in the ball and socket joint. However, it restricts translational motion because of the three reaction forces along the three dimensions.
Alternately joint B on the arm is a single smooth pin support. This support creates three reaction forces and two couple moments and allows the rotational motion along the axis of the pin.
The base of the robotic arm is fixed support, having reaction forces and moments along all three directions.
Another type of support is hinge support, used commonly in a door. Three reaction forces at the support restrict the translational motion of the door, while two moments restrict the rotation of the door.

ondersteuningsreacties in drie dimensies

Support Reactions in Three Dimensions

Ondersteuningsreacties in drie dimensies helpen de stabiliteit en evenwicht van verschillende structuren en systemen te behouden. Deze reacties voorkomen dat het systeem vertaalt en roteert, en zorgen ervoor dat het ontwerp bestand is tegen externe krachten en efficiënt en veilig zijn beoogde functie kan uitvoeren. Enkele van de ondersteuningen die ondersteuningsreacties in drie dimensies bieden, worden hieronder besproken: Een kogelgewricht is een van de ondersteuningen die vrije rotatie rond elke as mogelijk maken. Deze vrijheid van rotatie is mogelijk omdat er geen moment is dat de rotatie in het kogelgewricht beperkt. Het gewricht beperkt echter de translatie beweging door drie reactiekrachten langs de drie dimensies. Een ander type ondersteuning is de enkele gladde penondersteuning. Deze ondersteuning genereert drie reactiekrachten en twee koppelmomenten, waardoor rotatie mogelijk is langs de as van de pen terwijl beweging in andere richtingen wordt beperkt. Vaste ondersteuning levert reactiekrachten en momenten langs alle drie richtingen. Dit type ondersteuning zorgt ervoor dat het hele systeem stabiel en veilig blijft onder verschillende belastingen en omstandigheden, waardoor ongewenste beweging of vervorming wordt voorkomen die de functionaliteit van het systeem zou kunnen aantasten. Scharnierondersteuning is een ander veelvoorkomend type ondersteuning dat wordt gebruikt in de werktuigbouwkunde, vaak gebruikt bij deuren en andere soortgelijke toepassingen. Met een scharnierondersteuning beperken drie reactiekrachten bij de ondersteuning de translatie beweging van de deur, terwijl twee momenten de rotatie van de deur beperken. Deze opstelling maakt het mogelijk dat de deur om een ​​enkele as roteert terwijl stabiliteit en controle worden gehandhaafd.

Ondersteuningsreacties in drie dimensies

Support reactions in three dimensions help maintain the stability and equilibrium of various structures and systems. These reactions prevent the system ...

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Mechanical Engineering

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Equilibrium of a Rigid Body

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3d support types for stability and motion

Support reactions in three dimensions keep structures stable and in equilibrium. They stop unwanted translation and rotation, so a design can handle external forces safely and work as intended. These reactions are important in many structures and systems.

A ball and socket joint is one support that allows free rotation about any axis. It does not provide a moment that resists turning. At the same time, it restricts motion in space with three reaction forces along the three dimensions.

A single smooth pin support works differently. It creates three reaction forces and two couple moments. This setup allows rotation along the axis of the pin while restricting movement in the other directions.

Fixed supports provide reaction forces and moments in all three directions. They help keep the system stable and secure under different loads and conditions. This also helps prevent unwanted movement or deformation that could affect function.

Hinge support is another common support used in mechanical engineering, especially in doors and similar applications. It produces three reaction forces that block translational motion of the door. Two moments restrict the door’s rotation, but it can still turn about one axis.

3D Support Types for Stability and Motion

3d-support-types-for-stability-and-motion

conditions of equilibrium

Rigid Body Force Balance in Equilibrium

Rigid body equilibrium depends on a balance of external forces and moments. A rigid body is in equilibrium when it has no translational motion and no rotational motion. This happens when the net force and the net couple acting on the body are both zero. Internal forces are not used when checking equilibrium. These forces act in equal and opposite pairs inside the body, so they cancel each other. Because of that, they do not affect the overall motion or change in motion of the rigid body. The...

support reactions

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Types of structural supports control how a coplanar force system moves and reacts under load. A coplanar force system is a set of forces that all lie in the same plane. The supports create reactions at the point of contact. These reactions help keep a structure stable under external forces. Supports work by stopping translation with an equal and opposite force. They can also stop rotation by applying a couple moment in the opposite direction. In structural design, these reactions are important...

internal forces and center of gravity

Forces Inside a Body and Balance

Internal forces and the center of gravity help explain how objects stay in balance. These mechanics ideas matter for structures, machines, and vehicles that must remain stable under different loads and conditions. Internal forces are created inside a body when its particles interact. They can appear as tension, compression, or shear forces. These forces act in collinear pairs with equal magnitude and opposite direction. Between connected parts, they cancel each other and help keep the body in...

alternative sets of equilibrium equations

alternative-sets-of-equilibrium-equations

Equilibrium Conditions for a Supported Plate

Equilibrium conditions for a supported plate are used to describe when forces and moments balance. In this state, the plate has no net movement and no rotation. Engineers use these equations to study how structures behave under external loads. In many cases, the standard equilibrium equations are enough. But some systems need an alternative set of equations to match the geometry of the support points. A rectangular plate supported at points A, B, and C is one example. For this plate, the...

two force member

Two-Force Body Equilibrium

A two-force body is a rigid body acted on by only two external forces. In equilibrium, those two forces must have the same magnitude, the same line of action, and opposite directions. This balance is what keeps the body at rest. For a plate with forces F1 and F2 applied at points A and B, equilibrium means the sum of moments about any axis is zero. If moments are summed about point A, the moment from F2 must be zero. That means the line of action of F2 must pass through point A. The same idea...

three force member

Solving a Three-Force Member Example

A three-force member is a rigid body acted on by three forces at three points. The forces must have concurrent lines of action. If the forces are parallel, their lines of action stay parallel instead. A dumpster provides the example used here. It is connected to a pin support at point A and to a pin on a hydraulic cylinder at point B. The hydraulic cylinder acts as a two-force member in equilibrium. The dumpster weight acts through the center of gravity, and the support reaction acts at point...

equations of equilibrium in three dimensions

equations-of-equilibrium-in-three-dimensions

Checking Force Balance in 3D Structures

Checking force balance in 3D structures is a key step when a system is at rest. The vector and scalar equations of equilibrium are used to test whether a body is stable and will not collapse or fall apart. These equations give a clear way to study the forces acting on a body. The vector equations of equilibrium require the vector sum of all external forces on a body to equal zero. They also require the vector sum of the couple moments and the moments of all forces about a point to equal zero.

support reactions in three dimensions

Support reactions in three dimensions keep structures stable and in equilibrium. They stop unwanted translation and rotation, so a design can handle external forces safely and work as intended. These reactions are important in many structures and systems. A ball and socket joint is one support that allows free rotation about any axis. It does not provide a moment that resists turning. At the same time, it restricts motion in space with three reaction forces along the three dimensions. A...

constraints and statical determinacy

Constraints in Structural Equilibrium

Constraints in structural engineering control how a body can move and help keep it in mechanical equilibrium. A constraint is a restriction on motion. When the right number of constraints is used, the system can stay balanced with the fewest supports needed. A system with the proper number of supports is called statically determinate. In that case, the unknown reaction forces can be found from equations of equilibrium. These systems are the easiest to analyze and design because the forces can...

key terms and concepts

Learn how ball and socket joints, smooth pin supports, fixed supports, and hinge supports control movement and keep 3D structures stable under load.

3D Support Types for Stability and Motion | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

mechanical engineering

3D Support Types for Stability and Motion

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