Robotics
The cell is laid out around the person, not around the robot
Reach, speed and what happens when a gate opens come first. Everything else on the floor plan follows from them.
Why the safety standard comes first
A robot arm is a solved product. You can specify one from a catalogue, and the difficult engineering is almost never in the arm itself.
It is in the space around it. How far it can reach with the tool fitted, what it does when a light curtain breaks, how somebody clears a jam without stopping the whole line, and how the cell gets serviced. Those questions decide the floor plan, and the floor plan decides the cost.
Getting the order wrong is the expensive mistake. A cell laid out around the robot and then fitted with guarding afterwards usually needs more floor than the building has.
The cell
Safeguarded space, and then everything else
The drawing starts with the space a person must not be in while the machine moves, and with how the machine finds out that they are.
Light curtains, scanners, interlocked gates and the emergency stop are not accessories added at the end. Each one changes what the arm may do and how fast, and therefore how many parts an hour the cell produces.
Grippers
A claw knows where it is, not how hard it holds
Position is easy and cheap. A servo reports its angle and the controller knows where the jaws are to a fraction of a millimetre.
Force is neither. Measuring it needs a sensor and controlling it needs a loop fast enough to react before the thing being held is damaged. That is the difference between a gripper that handles steel and one that handles fruit, and it is why the second costs several times the first.
Working beside it
Speed and separation are one setting
A collaborative robot is not a robot that is safe because it is small. It is a robot that measures how far away a person is and slows down as they approach, stopping before contact.
That means throughput and separation are the same number seen twice. A cell where people are often close is a cell that runs slowly, and if the throughput calculation assumed full speed then the business case was wrong before anything was ordered.
So we measure how often somebody is actually in the space before promising a rate. It is a boring measurement and it has cancelled more than one project at a stage where cancelling was still cheap.
The choices
What has to be answered before an arm is quoted
In this order. Reversing it is how a cell ends up needing floor space that does not exist.
| Question | What it settles | What it rules out |
|---|---|---|
| What is being handled | Gripper, and whether force control is needed | Anything soft, if the budget assumed a simple claw |
| Who is nearby, and how often | Guarding, and therefore the real cycle time | Throughput figures taken from a datasheet |
| How a jam is cleared | Access, and whether the line has to stop | Layouts that need the whole cell powered down |
| Reach with the tool fitted | Floor area, which is the thing there is none of | Arms that fit the drawing but not the tooling |
The fourth row catches people. Published reach is measured to the wrist, and your tool adds to it in every direction.
Or write here
Three fields, and a person reads it
Name, an address we can answer to, and what you are trying to build. You get a reference back straight away.
What would the cell have to do?
Describe the part and who stands near it. That is enough for a first honest answer about whether a robot helps.