Key Criteria for Selecting Industrial Manipulator Before Investment

Today, industrial manipulators are no longer just auxiliary equipment to reduce manual labour for workers, but a technical investment that directly impacts safety, productivity, and long-term operating costs.

This article summarises the core criteria to evaluate before investing in an industrial manipulator, helping businesses choose the right solution that suits their actual needs and long-term operational goals.

1. Accurately define the actual operational problem

The most common mistake when selecting an industrial manipulator is starting with the load capacity instead of the actual handling process in production. In reality, two applications lifting the same 40–50kg object may require two completely different manipulator configurations.

Processes requiring an industrial manipulator

• Is it strictly vertical lifting and lowering, or does it also involve horizontal movement, rotating, or tilting the part?
• Is it a simple handling task or an assembly task requiring high precision?
• Is the load moved in an open space, or must it be reached deep into a machine, mould, or confined area?

Characteristics of the load

• Actual working weight (including tooling/end effectors).
• Shape and dimensions: compact, long, wide, or asymmetrical.
• Centre of gravity: close to or far offset from the manipulator's axis.

In many cases, the load moment generated by an offset centre of gravity is the decisive factor for the manipulator's structure, balancing capability, and operational stability, rather than the kilogram figure listed in the catalogue.

Working intensity of the industrial manipulator

• Number of lifting cycles per shift, per day.
• Continuous operation time.
• The number of operators and the degree of reliance on manual control feel.

Properly describing the handling task from the beginning helps the supplier select the right manipulator principle and design an appropriate structure, avoiding situations where the manipulator has excess power but is difficult to use, or has sufficient capacity but lacks stability.

In other words, the industrial manipulator should not be chosen based on the maximum load capacity, but on the most complex operation it must perform. This is the foundation for all subsequent technical criteria.

2. Movement trajectory & actual workspace

After accurately defining the handling task, the next criterion to clarify is how the manipulator will move within the actual workspace. This factor is often superficially evaluated but directly affects the usability and long-term effectiveness of the equipment.

Main movement trajectory of the industrial manipulator

• Does the manipulator only lift and lower vertically, or must it move along multiple axes?
• Is there a requirement to rotate or tilt the part (90°, 180°) during the operation?
• Is the movement continuous or between defined stop points?

Unlike traditional lifting equipment, industrial manipulators typically operate in a 3D space where the load not only moves but also changes direction, acceleration, and balance states. These movements create inertial forces and oscillations, requiring the manipulator system to be stable enough to control the load safely and accurately.

Workspace range

• Maximum reach radius
• Usable working height
• Limitations caused by factory ceilings, columns, machinery, and surrounding conveyors

In many projects, the manipulator has sufficient load capacity but cannot reach the final handling position, or it gets obstructed by the factory structure when fully extended. Consequently, the equipment is forced to operate in an evasive manner, reducing productivity and increasing handling risks.

Stability when halting the load

• Can the manipulator eliminate oscillations when stopped mid-stroke?
• Can it hold its exact position when the operator lets go?

These requirements are especially important in assembly stages, when loading workpieces into CNC machines, or when operating near personnel.

3. Selecting the appropriate drive technology

Drive technology is the core technical factor determining how the industrial manipulator reacts to the operator's movements, its precision level, stability, and operating costs throughout its lifecycle.

Pneumatic manipulators – A popular solution for standard operations

Pneumatic industrial manipulators operate based on the elasticity of compressed air, providing a light lifting feel and natural load floating. The biggest advantages of this solution are:

• Low initial investment cost.
• Safe operation, particularly suitable for flammable and explosive environments.
• Simple structure, easy to maintain.

However, the elasticity of compressed air itself limits precision when halting the load, especially in tasks requiring accurate positioning. Additionally, energy costs and losses due to air leaks during long-term operation are factors that must be considered.

Hydraulic manipulators – For extremely heavy lifting requirements

Hydraulic technology is suitable for heavy-duty applications where a high lifting force is needed while keeping the equipment relatively compact. Incompressible hydraulic oil helps maintain load stability better than compressed air.

However, in modern manufacturing environments, hydraulic manipulators are less preferred due to the risk of oil leaks, high maintenance costs, and unsuitability for the food, pharmaceutical, and electronics industries.

Electronic manipulators – High precision and control capability

Electronic industrial manipulators use servo motors combined with force sensors to assist operations in real-time. Outstanding advantages include:

• Precise control of position, speed, and acceleration
• Holding the load stable at any point in space
• High energy efficiency, low operating costs in the long run
• Easy integration with smart manufacturing systems

The main disadvantage of electronic manipulators is the high initial investment cost, requiring businesses to have a long-term perspective on the Total Cost of Ownership (TCO).

4. Precision & operational control feel

In many industrial applications, industrial manipulators must not only make lifting and lowering easier but also replace human hands in tasks requiring delicate control. Therefore, precision and motion control capability are criteria that cannot be overlooked, especially in assembly stages, loading workpieces into machines, or operating near personnel.

Determine the required level of precision during the operation

• Does the manipulator need to stop at any position along its stroke?
• Must the stopping position be accurately repeated between cycles?
• Is there a requirement to hold the load stable when the operator lets go?

In well-controlled systems, the load can remain stationary at a specific position without drifting, dropping, or oscillating, allowing operators to handle tasks more safely and accurately.

Ability to eliminate oscillation when stopping the load

When the manipulator moves in 3D space, inertial forces can cause shaking, especially with heavy loads or objects with an offset centre of gravity. If the system is not well-designed, residual oscillation will reduce assembly accuracy, increase the risk of collision with surrounding machinery, and cause fatigue and loss of confidence for the operator.

Control feel

• What is the required actuation force to move the load?
• Does the manipulator provide smooth, consistent feedback corresponding to human hand movements?
• Can the operator easily sense the load during the operation?

In modern manipulator systems, excellent motion control allows the operator to apply only a minimal force to move heavy objects while maintaining stability and precision throughout the entire stroke.

5. End effectors (Tooling) and product customisation capability

In many projects, manipulators are selected with the correct load capacity and drive technology, yet fail to achieve expected efficiency during operation. The root cause usually does not lie in the manipulator arm itself, but in the end effector (tooling)—the component that directly interacts with the product.

First, it is necessary to analyse the characteristics of the load:

• Shape: flat, round, long, asymmetrical.
• Surface: smooth, rough, porous, or non-porous.
• Rigidity and the capability to withstand clamping force.

For sheet materials or flat surfaces, vacuum suction end effectors are a common solution. However, a clear distinction must be made: non-porous materials (steel plates, glass, hard plastics) require high vacuum levels; porous materials (paper bags, cartons) require a large air flow rate to compensate for leaks.

In cases where the load has a complex shape or a surface unsuitable for vacuum suction, mechanical clamping is mandatory. Attention must be paid here: the clamping force must be sufficient to hold the load without deforming the product; the clamping mechanism needs to be stable during rotation, tilting, or rapid movement; and force sensors or clamping force limiters should be integrated for sensitive products.

For steel plates or metal workpieces, magnetic end effectors provide high handling speeds. However, safety must be the top priority, especially during power outage scenarios.

In addition to gripping capability, the end effector must be evaluated for future flexibility: is it easy to swap out for different-sized products? Can it be shared across multiple product lines? Is changing the tooling time-consuming and costly?

6. Safety & compliance with standards in Vietnam

Industrial manipulators are equipment that work directly alongside humans; therefore, safety is a mandatory prerequisite for any investment decision. A smoothly operating system that lacks appropriate safety mechanisms still poses significant risks in daily use.

Consider potential loss-of-control scenarios

• Sudden loss of power or compressed air.
• The operator lets go while the load is mid-stroke.
• Exceeding the permitted load capacity due to operational errors or product changes.

In such cases, the manipulator must be equipped with active and passive safety mechanisms, including: anti-drop load structures (check valves, mechanical brakes, or controlled descent systems), stroke and overload limits, and an easily accessible, instantly responsive emergency stop button (E-stop).

=> Read more: Mandatory safety features of industrial lifts assist

Requirements for compliance with standards and regulations in Vietnam

Industrial manipulators fall under the lifting equipment category; therefore, they must comply with regulations such as TCVN 4244 for design, manufacturing, and technical safety inspection, and QCVN 07 on occupational safety for lifting equipment, which includes initial and periodic inspections during use.

Ignoring or underestimating the inspection process not only leads to accident risks but also entails legal risks, directly affecting the enterprise's production activities.

=> Read more: Lifting equipment standards – Mandatory regulations businesses must know

Consider specific working environments

• Areas with explosion risks, high dust, or flammable vapours.
• Food and pharmaceutical industries require clean, easy-to-sanitise materials.
• Workspaces near operators or crowded production lines.

Each environment will demand different safety solutions, ranging from the choice of drive technology to construction materials and installation methods.

7. Installation infrastructure & foundations

No matter how well-designed an industrial manipulator is, it cannot operate efficiently if the installation infrastructure is unsuitable. In reality, many projects incur extra costs and prolonged implementation times simply because factory conditions were not fully assessed from the outset.

First is the foundation structure and load-bearing capacity. When the manipulator operates at a long reach with a significant load, the force exerted on the floor is not just the static load but also includes the overturning moment and dynamic forces generated during operation. Therefore, it is necessary to check: the thickness and strength of the concrete floor, the load-bearing capacity of anchor bolts, and the vibration level and stability of the factory floor.

If the existing floor does not meet the requirements, plans for foundation reinforcement or pouring an independent foundation must be calculated upfront in the investment budget to avoid a situation where the equipment is purchased but cannot be installed.

Next are the installation options: floor-mounted (column type), overhead rail systems to expand the working range, or mobile bases for multiple workstations. Each method has its own pros and cons, depending on the factory layout, machinery density, and future expandability.

Beyond mechanical factors, integration with existing production lines must also be considered: does the manipulator obstruct walkways or worker safety zones? Does it hinder the maintenance of surrounding machinery? Can it be relocated or expanded when the line is upgraded in the future?

8. Total Cost of Ownership (TCO)

One of the reasons many companies misjudge the ROI of industrial manipulators is that they only compare the initial purchase price without fully looking at the total costs throughout the equipment's lifecycle. In reality, the initial investment is just a fraction of the long-term financial equation.

Total Cost of Ownership (TCO) considerations should include:

• Initial equipment purchase and installation costs
• Energy costs during operation (electricity or compressed air)
• Maintenance and consumable parts replacement costs
• Downtime costs due to unexpected breakdowns or unplanned maintenance

For pneumatic manipulators, the initial investment is usually low, but operating costs are higher due to lower energy efficiency and losses from central compressed air systems.

Conversely, electronic manipulators typically have a higher initial cost but make up for it with high energy conversion efficiency, fewer consumable parts, and a significant reduction in maintenance and unplanned downtime costs.

Additionally, indirect costs should be factored in: the equipment's impact on productivity and cycle times, operator fatigue levels and occupational accident risks, and the ability to expand or repurpose the system when products change.

When weighing these factors over a 5–10 year cycle, many solutions that seem expensive initially turn out to be the more economical choice in the long run.

9. Supplier & technical support capabilities

Many businesses often underestimate this final criterion, when in fact, it is the deciding factor in a project's success or failure. An industrial manipulator is not an off-the-shelf, plug-and-play device; it is an engineered solution tailored to the specific challenges of each factory.

First, observe how the supplier approaches your needs: do they conduct actual site surveys or just consult via a catalogue? Do they ask questions about the handling operations, movement trajectories, and work environments? Do they analyse the risks and limitations of each option?

A professional supplier will not start by giving a quote; they will start by fully understanding the production problem.

Next is their design and customisation capability: is the manipulator custom-designed for the product and factory layout? Is the end effector calculated and tested before handover? Are there simulations or demonstrations for operators to evaluate beforehand?

During operation, after-sales service is what most clearly reveals a supplier's capability: response times to incidents, availability of spare parts, maintenance support, inspection assistance, and operator training.

Especially for long-term projects, the level of partnership must be assessed: can the system be upgraded or expanded when products change? Do they support adjustments when production processes evolve? Do they have an in-country technical team, or do they rely entirely on third parties?

Vietmani - The genuine manufacturer of industrial manipulators in Vietnam

VIETMANI – Vietnam Manipulator Joint Stock Company is one of the rare entities in Vietnam that directly researches, designs, and manufactures industrial manipulators, rather than merely distributing or assembling them.

Founded in 2019, VIETMANI has a clear focus on the field of industrial lift assists and lifting support equipment, with a product ecosystem that includes: Pneumatic manipulators (HA series), pneumatic cable manipulator (HAS series), Articulated jib cranes, overhead rail systems, and customised lifting solutions on demand.

A crucial advantage of VIETMANI lies in its turnkey implementation capability: on-site surveys and operational analysis, designing solutions tailored to the factory layout and production processes, installation, operational training, inspection assistance, maintenance services, warranties, and long-term domestic technical support.

Contact Vietmani for a free consultation and site survey. Hotline: 0931 782 489.