Chocolate Confectionery Robot: ABB FlexPicker Pralines

A box of pralines holds a dozen or more different pieces, each in its own spot, and somebody has to put them there without a fingerprint or a crack. Packing those boxes was one of the first jobs a chocolate confectionery robot was built for. This post follows the work from hand dipping and packing rooms to enrobing lines, then to the delta robot that was invented with pralines in mind and ABB's FlexPicker that made it common. It ends with what this year's cocoa prices mean for automation, how home chocolatiers fit in, and what robots still cannot do well with chocolate.

A box of Lindt Pralines Classic, each piece in its own spot in the tray. Photo: Lg09 / Wikimedia Commons (public domain)

From hand dipping rooms to enrobing lines

For most of the 19th and early 20th centuries, filled chocolates were made almost entirely by hand. Rudolphe Lindt invented the conche in Bern in 1879, which made smooth chocolate possible, and factories such as Cadbury's Bournville, opened the same year, grew quickly. Centers were still dipped one at a time by skilled hand dippers, who lowered each piece into melted chocolate and lifted it out with a fork. Wrapping and boxing were done by rows of women at long tables, as photos from the 1920s show.

Workers in a chocolate wrapping room in Claremont, Tasmania, 1925. Photo: unknown photographer via Wikimedia Commons (public domain)

The first big machine in this part of the factory was the enrober. It was invented in France in 1903 and later brought to the United States, where it could do the work of about twenty dippers. Pieces ride on a wire mesh belt through a curtain of tempered chocolate, a blower removes the excess, and a cooling tunnel sets the coating. Moulding lines followed for bars and shells. Packing stayed manual for decades because every praline in an assortment is a different shape.

A chocolate enrobing machine coating bars at the Camille Bloch chocolate museum in Courtelary, Switzerland. Photo: Peter Potrowl / Wikimedia Commons (CC BY-SA 4.0)

The robot built for that job came out of a chocolate factory visit. In the early 1980s Reymond Clavel's team at EPFL in Lausanne designed the delta robot after watching pralines being packed by hand. It uses three light arms joined at one small platform, so it can move very fast. The design was patented in 1985, and the Swiss company Demaurex took a licence in 1987. ABB launched its own delta robot, the IRB 340 FlexPicker, in 1998 and listed packing mixed pralines into blisters as one of its typical jobs. The second-generation IRB 360 followed ten years later.

ABB's second generation FlexPicker delta robot picking small packs off a conveyor. Photo: ABB

Cocoa prices, pralines and FlexPicker lines today

Chocolate makers are under pressure this autumn. On 29 September Lindt & Sprüngli cut its 2026 sales growth forecast to between 0 and 2 percent, blaming summer heatwaves and the price increases it had to make after cocoa costs rose. Reuters reported cocoa prices up about 80 percent in six months, and Lindt said its premium gift boxes and praline assortments saw the sharpest drops in volume. When every broken praline costs more, careful handling and less waste matter more on the line. Heat matters too, since a warm packing hall softens chocolate before it reaches the box.

Cocoa farmers opening pods during the harvest, the start of a supply chain whose prices rose sharply this year. Photo: ICCFO / Wikimedia Commons (CC BY-SA 4.0)

Packing pralines is still the job where robots are most at home. In Sweden, the pastry maker Delicato installed four ABB IRB 360 FlexPicker robots at its bakery in Segeltorp, south of Stockholm, to pick its chocolate-covered Delicato balls off the conveyor and place them in blisters. The system, built by integrator Evomatic, uses ABB's PickMaster vision software to find each piece on the moving belt. ABB said the cell cut production costs and improved hygiene, and it freed workers for other tasks.

ABB IRB 360 FlexPicker robots picking chocolate balls at Delicato. Photo: ABB

The FlexPicker suits chocolate for a few reasons. It picks at high speed with light vacuum or soft grippers, it follows products on a moving belt with conveyor tracking, and wash-down versions can be cleaned with water and detergent between runs. A camera finds each piece, so pralines do not need to arrive lined up, which saves building a separate feeder to line them up first. Other confectionery lines are automating too: on 28 September Food Business News described gummy lines with automated mould handling that reach 1,000 kg per hour.

A wash-down FlexPicker being sprayed clean, as food lines require. Photo: ABB

Where chocolate robots go next

Over the next few years, flexibility matters more than raw speed. Chocolate makers sell many short seasonal ranges for Easter, Halloween and Christmas, and each needs its own tray layout and assortment. With vision and recipe-based software, a FlexPicker cell can change layouts in software instead of being rebuilt for each season. The same kind of robot can take on jobs further up the line too, such as placing nuts on top or handling moulds. ABB's packaging line robots show how the same arms finish the job with case packing and palletizing.

An operator watches the FlexPicker packing cell at Delicato's bakery. Photo: ABB

At home, robots are a long way off, but machines already help. Many hobby chocolatiers use a small tempering machine or a thermometer to hold chocolate at the right temperature, because untempered chocolate sets dull and soft. A cobot such as ABB's GoFa could, as a possibility, help a small chocolate shop dip, decorate or pack at busy times, and it would stop when it touched someone. Today that is rare, and small makers still do almost all of it by hand.

Tempering chocolate at home: letting it cool to about 29 degrees Celsius before use. Photo: Roozitaa / Wikimedia Commons (CC BY-SA 3.0)

Chocolate is a hard material for robots. It softens from the heat of a gripper or a warm room, glossy surfaces scuff easily, and fine hand decoration is hard to copy. A cell has to be cleaned well enough for food rules and kept dry around melted chocolate. Cost decides a lot: a delta robot cell pays off on high-volume lines but is hard to justify for a shop making a few hundred boxes a week. The people who programme and maintain these cells need training too, and ABB's PickMaster software is where many of them start.

PickMaster Lite runs on ABB's OmniCore controller and links to RobotStudio. Photo: ABB

Innovation

AI solutions for effortless ABB robot control.

Automation

Robotics

ceojohntran@chatwithrobot.net

+84905311611

© 2025. All rights reserved.

qtran1215@gmail.com