Robots enter the chicken shed

Free-range egg production may soon be transformed by robots that collect eggs from the floor – if a Dutch biosystems engineer has his way.

Eldert van Henten, head of the Farm Technology Group at Wageningen University in the Netherlands, and his team have designed a prototype egg-picking robot. Dubbed the PoultryBot, it was presented at the world’s biggest industrial fair, Hannover Messe, in April.

Compared with many of the sleek robots and futuristic vehicles displayed at the fair, the bot looks clunky – and that is before it is covered in messy wood shavings in a chicken shed. But it contains technology that farmers are crying out for. Egg picking is “a tough job,” said van Henten, given that some free-range producers have 10,000 laying hens. 

The story affects us all as consumers of some 180 eggs per person per year. In Europe, battery cages for laying hens were banned in 1999 and replaced by free-range systems where, usually, the hens lay eggs in their nests. “But sometimes they don’t, and then they lay eggs in the litter on the floor,” said van Henten. These must be collected before they go off, and because they tend to encourage other chickens to lay their eggs on the floor too.

To develop the robot, the team used off-the-shelf hardware, including a laser scanner for localisation and to collect data points of the environment, a camera looking for eggs, and odometry that guides velocity, acceleration and directional changes.

The researchers were at first concerned that the machine might upset the hens. But they found that after a day or two the birds were instead intrigued, actively pecking at it, even lying on top of it. “We may have to produce a chicken-proof model,” quipped van Henten.

The team also had to make sure the robot could pick up the eggs without breaking them, which it does using a rotating basket. Production models will need to have storage bins that will be emptied automatically during recharging. “Eggs are quite fragile, and when this becomes a product, it should be easy to use with proper user interfaces and servicing built in,” said van Henten.

The PoultryBot’s navigation, localisation and collision avoidance system had to be simple to keep costs low. The software includes algorithms that guide the robot through the farm building as it sweeps the floor for eggs. These tell the robot to prioritise locations where the eggs are frequently laid, such as dark spaces. Known locations are 3D mapped and the software is automatically updated.

The bot can also carry sensors to monitor animal status and behaviour, as well as temperature, humidity and dust levels in the hen house.