At some point in the life of any robotic installation, the question stops being 'What is failing now?' and becomes 'Does it still make sense to keep maintaining it?' There is no universal answer, but there are clear criteria that allow you to make the decision based on data rather than gut feeling.
The most common mistake: deciding by age
The age of the robot is the worst indicator for this decision. A robot with 18 years of service that has been well maintained, has available spare parts and a stable workload can still be profitable for years to come. Conversely, a 10-year-old machine with a poor maintenance history can be a genuine economic burden.
The indicator that matters is total cost of ownership: the sum of preventive maintenance, corrective interventions, parts, downtime and lost productivity. When that annual cost approaches or exceeds the amortisation cost of a new equivalent machine, renewal starts to make financial sense.
Signs pointing towards replacement
- Discontinued parts or long lead times: when sourcing a component requires systematically searching the secondary market, the exposure to extended downtime risk is high. For more on managing this risk while the equipment remains in production, see our article on which critical spare parts to keep in stock.
- End of manufacturer support: without security updates or official support for the controller, any software or hardware incident becomes a problem with no safety net.
- Increasing breakdown frequency: two or three corrective interventions a year can be normal; five or more on the same machine, with different symptoms, indicate systemic degradation.
- Inability to meet current production requirements: if the line has evolved and the robot cannot adapt, the opportunity cost counts too.
- Inability to certify functional safety: updated regulations may require safety functions that older controllers do not implement natively.
Signs pointing towards repair or modernisation
- The mechanical arm is in good condition and failures are concentrated in the controller: in that case, replacing the controller is an intermediate option with lower cost and impact than a full renewal.
- Spare parts are still available — original or reconditioned — at reasonable prices and with acceptable lead times.
- The workload has not changed significantly and the robot meets the required tolerances.
- The integration cost of a new machine far exceeds the cost of repair.
The intermediate options that are often overlooked
Between 'repair everything' and 'buy new' there is a range of solutions that is often dismissed through lack of awareness:
Controller retrofit
This involves replacing the control cabinet with a more recent generation while keeping the mechanical arm. It reduces exposure to software obsolescence and allows modern safety functions to be incorporated without renewing the mechanics, which is typically the most expensive part.
Scheduled full overhaul
A deep intervention on gearboxes, bearings, internal cabling and the braking system can restore the robot's original performance and extend its useful life by several years at a significantly lower cost than a new machine.
Controlled capacity expansion
In some cases, the solution is not to replace the existing robot but to add a second unit that absorbs the additional load, keeping the first one handling the tasks it was originally sized for.
Building the economic case
To present the decision to management with solid data, it helps to structure the analysis in three columns:
- Scenario A – Continued maintenance: estimated annual cost of preventive work, corrective interventions and parts over the next three to five years, plus the risk of extended downtime if a critical component is unavailable.
- Scenario B – Partial modernisation: investment in retrofit or overhaul, production impact during the intervention and expected savings in corrective maintenance.
- Scenario C – Full renewal: cost of the new machine, integration, programming, validation and amortisation, weighed against the productivity or availability gain it delivers.
In many cases, Scenario B is the clear winner over a three-year horizon, especially when the machine has a solid mechanical foundation and the integration cost of a new robot would be high.
The role of an independent service provider
An independent technical service can audit the real condition of your equipment without the commercial bias of someone trying to sell a new robot. At PAS Robotics we carry out technical audits that assess the mechanical condition, spare parts availability and projected cost of each option, giving plant managers the data they need to decide with confidence.
If the decision points towards renewal, our robotics integration team can plan the transition to minimise production impact. If it points towards continued maintenance, our maintenance contracts provide the coverage needed to reduce the risk of unplanned stoppages.