Motion control for automotive and EV manufacturing

In short:Automotive and EV lines use electric servo actuators for spot welding, clinching and press-fitting, servo motors and linear motors for handling and battery cell stacking, and safety-rated drives on every axis. Size each axis from the force or torque at the worst moment of the cycle, then check RMS heat, screw life and the data the process needs to record.

Typical requirements

Machinery we specify motion for

• Body-in-white spot welding guns
• Clamping, hemming and clinching stations
• Press shop die change and part transfer
• Paint, adhesive and sealant dispensing
• Final assembly lifting and pressing stations
• Powertrain and wheel bearing presses
• Battery cell stacking, winding and welding
• Traction motor production lines
• End-of-line test and quality inspection
• Tyre building and green tyre transfer

What automotive and EV production demands from motion

Automotive lines run two or three shifts, take a stoppage seriously and record almost everything. Motion components on these lines face high cycle counts, weld spatter, coolant and adhesive, and a quality system that wants force, position and torque data for each part. The UK alone built 717,371 cars and 47,344 commercial vehicles in 2025 according to SMMT, supported by more than 2,500 component suppliers, so the same station designs are repeated across many plants and Tier 1 cells.

The move to EVs has added battery cell, module and pack lines and traction motor lines to the traditional press, body, paint and final assembly shops. Those new processes are faster, more precise and often run in dry rooms, which changes what the linear and rotary axes must do.

Two trends shape component choice:

• Electric replaces pneumatic and hydraulic wherever force, position or speed must be controlled and recorded: weld guns, clinching heads, press-fit stations and die-change equipment.
• Direct drives replace mechanical transmission where speed and accuracy matter most: linear motors on battery stacking axes and direct-drive rotary motors on dial tables.

Where each motion component sits on an automotive line

Tolomatic’s automotive application list maps electric actuators onto every shop. The table below adds the other components that go with them.

Servo weld guns and electric presses

Resistance spot welding is the classic case for electric actuation. Tolomatic’s weld quality article sets out the argument: a servo actuator delivers the same electrode force on every weld, while pneumatic force wanders with air pressure, causing weak welds at one extreme and burn-through at the other. Burn-through also damages the tips, so servo guns keep tips in service longer. The gun opens only as far as the next weld position needs, rather than fully, which shortens each cycle. Published ServoWeld examples run at 4.2 kN and 14.7 kN.

Electric presses follow the same logic. A roller-screw actuator with a servo motor gives full force anywhere in the stroke, an approach speed several times the pressing speed and a programmable force-position profile. Tolomatic lists wheel bearing pressing, powertrain assembly and air bag cartridge assembly among its RSX and RSA applications. Monitored press systems such as Kistler’s joining system record force and displacement for every joining cycle against set limit windows, which is what automotive quality plans usually ask for.

For a conversion from hydraulics, read our hydraulic to electric actuator guide and compare ball screw vs roller screw.

Motion for EV battery manufacturing

Battery cell production is a sequence of web handling, cutting, stacking or winding, welding and inspection. Renishaw describes encoders monitoring component position, speed and direction across stacking, winding, welding and inspection, and measuring rotor position on traction motor lines.

The pace is the challenge. In a research line at TU Berlin described by Beckhoff, a 50 Ah pouch cell holds up to 53 electrodes of 300 × 125 mm. Continuous Z-folding with linear movers cut the fold time from over 1 s to 0.7 s, with a target of 0.35 s. At 0.7 s the movers travel at about 600 mm/s; at 0.35 s they need about 1,000 mm/s. The project team notes that accuracy drops at higher speed because of vibration and inertia, and it uses timestamped position capture so detection does not depend on the PLC cycle.

What that means for specifying:

1. Use linear motors for the fastest short-stroke axes. No screw to whip or wear, and force is available at any speed. See linear actuators for motor types.
2. Size from settling, not just move time. The axis must settle inside the placement tolerance before the next pick. Ask for structure stiffness and encoder resolution together.
3. Capture position on an event, not on a scan. Latch encoder position in hardware when a sensor fires.
4. Check dry-room and particle rules early. Lubricants, cable chain wear and exposed magnet tracks may all be restricted.

How to size an electric press-fit station: a worked example

Take a wheel bearing press needing 40 kN at the end of a 120 mm stroke, approaching at 100 mm/s and pressing the last 10 mm at 10 mm/s. Cycle time is 10 s.

1. Screw torque at peak force. With a 5 mm lead roller screw and an assumed efficiency of 0.8, torque = F × lead ÷ (2π × η) = 40,000 × 0.005 ÷ (2π × 0.8) ≈ 40 Nm at the screw.
2. Reduction. A 2:1 belt reduction gives about 20 Nm at the motor, before belt losses.
3. Speed. 100 mm/s ÷ 5 mm = 20 rev/s = 1,200 rpm at the screw, so 2,400 rpm at the motor.
4. RMS torque. Say 1 s ramping to peak (average 10 Nm), 0.5 s holding 20 Nm, 3 s of approach and return at 2 Nm and 5.5 s idle. RMS = √((10² × 1 + 20² × 0.5 + 2² × 3) ÷ 10) ≈ 5.6 Nm.
5. Choice. A servo motor with about 6–8 Nm continuous and at least 20 Nm peak covers it, leaving margin for belt losses and a hotter cabinet. A roller-screw actuator in the class of the RSA-HT (published to 58 kN) suits the force.
6. Life. Calculate screw L10 life at the equivalent load over the real cycle, not at peak force alone.

Treat these figures as an illustration; use the manufacturer’s efficiency and life data for the actual screw.

Things that catch engineers out

1. Sizing the press for peak force but not hold time. Holding 40 kN for several seconds heats the motor as much as moving does.
2. Trusting motor current as the quality record. Fit a load cell where each joint must be proven.
3. Fieldbus through a rotary table on ordinary rings. EtherCAT and PROFINET need Ethernet-rated slip rings; read Ethernet through slip rings.
4. Weld spatter and coolant on actuator rods. Specify wipers, boots or a higher IP rating.
5. Forgetting STO and brake tests on vertical axes. Lift stations and press rams need a holding brake and a tested safe stop.
6. Assuming the 2027 machinery rules are far off. Regulation (EU) 2023/1230 applies from 20 January 2027 for machines placed on the EU market.

What to send an engineer

• Station type and process: welding, pressing, clinching, stacking, dispensing or handling.
• Force or torque at each step of the cycle, stroke, approach and working speeds, cycle time and shifts per day.
• Moving mass, orientation (vertical axes need a brake) and the space available.
• Environment: weld spatter, coolant, adhesive, washdown, dry room or clean zone.
• Fieldbus, controller platform and encoder interface the line standardises on.
• Safety functions and target PL or SIL from the risk assessment.
• Process data to record per part, such as force-displacement curves.
• For conversions, the bore, rod size and pressure of the existing pneumatic or hydraulic cylinder.

Send the station’s force, stroke, cycle and safety requirements and our specialist engineering and supply partners can propose a matched actuator, motor, drive and feedback set. You can start in the spec builder.

Standards to have in view

• Regulation (EU) 2023/1230 (machinery; applies from 20 January 2027, replacing Directive 2006/42/EC)
• ISO 13849-1 (safety-related parts of control systems, performance levels)
• IEC 62061 (functional safety of machinery control systems, SIL)
• IEC 61800-5-2 (adjustable speed drives: functional safety, STO, SS1, SLS)
• EN 60204-1 (electrical equipment of machines)
• ISO 10218-2:2025 (robot applications and robot cells)
• IEC 62135-1 (resistance welding equipment: safety requirements)

Which standards apply depends on the end product and its market. Your engineer will confirm what the component itself needs to meet.