In its simplicity, how can a robot’s handling capacity or maximum payload be determined? For example, the ISO 9283 standard focuses only on the definition of accuracy and repeatability, and there is no information on testing or defining a payload. Scientific articles mainly focus on determining the maximum payload in a given trajectory. What if the trajectory is unknown? Clearly related to the definition of the payload, the torque constraints of the actuators and other considerations are the dynamic and kinematic modeling of the manipulator. And stability in wheeled manipulators. I would be grateful if you could provide information and proper sources for defining and testing your maximum payload. I am not yet an expert in the field.
How to determine the maximum payload for a robot
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payloader -
April 6, 2022 at 4:32 PM -
Thread is Unresolved
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- Best Answer
construction and used components will define maximum stress arm can endure. they are selected based on requirements for specific model. this can get you pretty good info what may be possible with specific design. normally if you gradually increase load you will reach point where system is not able to react as expected. then you can do stress tests to confirm that robot system is able to operate in certain condition over long time without overheating, premature wear etc. The actual rating you list in specs is data you come up with - it is compromise between performance and reasonable service life.
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construction and used components will define maximum stress arm can endure. they are selected based on requirements for specific model. this can get you pretty good info what may be possible with specific design. normally if you gradually increase load you will reach point where system is not able to react as expected. then you can do stress tests to confirm that robot system is able to operate in certain condition over long time without overheating, premature wear etc. The actual rating you list in specs is data you come up with - it is compromise between performance and reasonable service life.
Thanks a lot, wise words! Could you or other pals provide appropriate sources from which I could read more on the subject? On topics like robot building, load testing, and stress testing. And other answers are more than welcome. It would also be useful to look at this in more detail.
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well, it starts all with introduction to Physics (energy, gear ratio, friction, inertia etc.).
when one is designing axis, motor, gearbox etc. are selected with certain goal in mind.
then that axis and chosen payload become new payload for axis that caries them etc.
one can do math without building the system and even with model that is not too complex still get pretty good results. but the ultimate test is always physical reality. there is no point in building infinitely complex model to do calculations at some point one need to just go ahead and build the unit and measure actual performance.
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simple answer: check the spec
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@yoav biren
what do mean by "haha"?
In the robot specification of the robot you will find a diagram answering the question asked in this thread!
Explain in more detail the reason for "haha". Or do you want just collecting points?
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Robot specification sheet will specify mass moment of inertia MMI limits for Joint5 and Joint6, sometimes also Joint4.
MMI values will specify the maximum torque the joint can handle by motion equation
Torque = (MMI) x (Alpha).
MMI is a directly related of your end effector mechanical design (mass, size, etc.). For example, SolidWorks used its Mass Properties function to calculate an end effector assembly model's MMI about specified axes.
These MMI limit values are developed experimentally by the manufacturer for full payload & full speed motion in all configurations. Limits are due to motor torque and gear train design in order to meet repeatability specifications and survive the design service life. MMI values can be exceeded if speed is reduced. The reduction amount is not specified and usually determined by experimentation and experience.
If the end of arm tool has any additional loading (such as forces applied to a milling cutter), then these forces will apply torques to the joints 5 & 6. These additional torques must be accounted for in the overall payload analysis.