OPERATOR’S FATIGUE OF

HAND TRACTORS

GROUP NO :1

Hand Tractors Usually used in developing

countries For land preparation in dry &

wet conditions Suitable for small size fields Operator guide the machine by

walking along behind it

Operator’s fatigue

During field operations hand tractors impose a greater work load on the operator

Its results in fatigue Needs more human energy than a

conventional tractor

Important Short Comings in field Operation

Excessive vibration feel as the hand grip Uncomfortable postures Vibration cause diseases in hands

Vibration syndrome Finger disorder Causing pain Loss of ability to hold the controls

Work related fatigue Work related pain

Cont…..

Hand Tractor’s Human Energy Demand

The human energy demand in the operation of a hand tractor is influenced by

Forward speed The machine balance The type of task (wet land/dry land)

How to Reduce Operator’s Fatigue???

A hand tractor was modified to enable operation in a seated position

The seated posture of operation requires minimal muscular effort

Reduce the pressure

A Hand Tractor Operator Seat should be comfortable

to control; Steering Clutch Break Clutch High-low speed change lever Main speed change lever Blade speed change gear lever

Other Hints for a Comfortable Seat..

Back support & foot rests Ensure Stability Proper seat moments for different

operators

Design of a seatSeat pan Strong enough to support

the weight of an operator up to 80kg

Leaf spring Support the seat & acted as a shock absorber

backrest Small backrest of 200mm & depth of 360mm

footrest Care was taken to ensure comfort in the seated posture

Advantages of incorporating a Hand

Tractor seat… Reducing Human energy consumption. Reducing the operational time. Increase the efficiency for road transport Reducing Work related body pain. Reducing vibration intensity in

acceleration.

References

“Operator’s Fatigue in Field Operation of Hand Tractors” V.K.Tewari , K.N.Dewangan, published online on 24th July 2004

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