26 October 2001

NEAT SOLUTIONS TO PLANTING PROBLEMS

Last year, Norfolk farm

worker Philip Boyce took

second prize in the complex

category of the farmers

weekly/Barclays Farm

Inventions Competition.

Andrew Pearce catches up

on whats happened since

IF YOUVE ever planted peat-blocked lettuce from a manual machine, youll know exactly what Philip Boyce means when he says its dirty, back-breaking work. And when rain comes and handwork takes over, the job gets nastier still.

Part of the answer lies in trailed semi-automatic kit, which although still hand-fed does the actual planting mechanically. The Italian-built Ferrari machine (red, but no relation to the slightly faster Maranello product) is common in the UK, but is designed for drier, hotter climes. Wet conditions soon force a shift to handwork, doubling establishment cost, halving progress and bringing general workforce gloom.

Hundreds of hours on old-style machines gave Mr Boyce plenty of time to work out a way forward.

He reckoned several areas needed sorting out: The Ferrari uses individual planting heads to put four rows of lettuce into a pre-formed bed. Each head is hand-fed with peat-blocked lettuce in clumps of ten (see 4-6). Oil and air power lets the heads tease off a single block and drop it into a slot opened by a coulter shoe.

Spacing information comes from a sensor carried on a bed-firming cage roller ahead of the planting section. Working through electronic controllers, the sensors signal triggers the planting sequence. When wet land bungs up the cage wheel and surrounding area, the roller slides and spacing goes to pot. His solution? Relocate the cage roller to the front of the machine, making it lift out of work, and take spacing cues from a wheel.

Semi-automatic machines need pto power for their air compressor, so the tractor driver has to work at fixed revs. In poor conditions this limits the outfits speed flexibility; hydrostatic drive would get round it.

&#42 Snug and warm

On trailed machines the driver might be snug and warm, but cant easily see or hear whats going on behind. A self-propelled planter can give the driver a birds eye view.

Trays of lettuce blocks arrive on site palletted. Existing planters struggle to carry enough trays for round-trip operation, and have to be backed up to a trailer for hand loading and emptying. Switching to a pallet handler would cut turn-round time, while a physically bigger planter could carry many more trays.

A re-design could improve operator safety in several ways, as well as giving the control electronics a weatherproof home.

Little Gem lettuces are still planted by hand, as no current machine can cope with their small size and five-row growing system. An interchangeable planting section could let one machine handle all varieties.

A new machine could plant any vegetable raised in peat blocks, opening up a wide market.

&#42 Back of the mind

All this stewed in the back of the Boyce mind until 1999, when a mate rang to say he had an old Matrot six-row beet harvester. Eighteen months and a great deal of effort later the prototype Plantmaster rolled from Mr Boyces Pudding Norton, Fakenham workshop straight into the field, and after a couple of weeks he knew he was on the right track.

But there was a snag. Development costs money, and apart from a very welcome SMART micro-project award everything therefore had come from his own pocket. To move the now-patented design along he needed a backer. Enter Ashley Wright, MD of local company Dolphin Utilities Ltd and an old friend.

His input will allow vegetable machinery specialist Nicholsons to modify the protoype to include features originally planned (see Box: All change), then take it into production. Well keep you updated on that, but until then heres a look at the prize-winning original.

The prototype Plantmaster featured here proved the concept. The revised model will still use Ferrari units, evolving as follows:

&#8226 Currently the whole planting unit subframe lifts out of work. To minimise disturbance to trays and operators, only the units themselves will lift.

&#8226 The cage roller will disappear. Planting sequence will be triggered by front tyre rotation.

&#8226 Wider rear rims will help flotation while keeping within bed wheelings.

ll The rear tray lift will be replaced by fold-down carriers on each side. Loading full pallets and unloading empty trays can then be done mechanically at the headland.

&#8226 The meshed-in tray holding area will disappear.

&#8226 To maximise planter unit stability, the chassis pivot will move from the rear to behind the front axle.

&#8226 Electronic control units will move into an improved cab.

Also in the pipeline are systems to deliver spray and slug pellets to each planting unit. For more details, contact Philip Boyce (01328-851398).

All change

1. The first Plantmaster carries its modified Ferrari planting unit in a subframe, lifted out of work by rams. To minimise wet-weather blocking the original full-width cage roller (front) was cut down, but retained to drive the standard plant spacing sensor.

Philip Boyces Plantmaster on its first day out. Note the relocated cage roller.

2. Four operators stand with their backs to the direction of travel. To give the centre pair headroom, the Matrots chassis gained an up-and-over section. Empty trays are stacked either side on the blue carriers, which fold up for transport. The revised prototype will have hydraulic lifts, able to take complete pallets.

3. Lettuce plants (raised in peat blocks, usually by an external supplier) arrive at the field in trays. Where the Matrots cleaner system once whirled, a lift platform takes trays to a roller conveyor. This wont be needed in the revised model.

4. Filled trays are slid on to a meshed-in holding area over the planter. Philip Boyce wields the stainless steel scoop used to slide sets of ten blocks on to a belt…

5. …which takes the blocks down to the planting head (right).

6. The planting head, seen from an arriving blocks standpoint. Air-operated grippers (A) hold a set of ten blocks. Plants can be spaced every 6-12in along the row, with delivery triggered by a signal from a distance sensor. When the signal arrives, a pair of oil-driven wheels (B) spin briefly and tease out

a plant, which drops into

a soil slot.

7. Matching the Matrots track to 80in beds caused some problems. While simple spacers sorted out the front axle, the rear needed new, different-offset rims.

8. Misses happen with any mechanical planting system. Standard practice is to have two people walking behind to fill any gaps, so in work this rack holds a supply of plants.