The research and study topics in this page are listed below. Click on the relevant subhead to go to the section

• MATERIALS USED IN THE FABRICATION OF THE COACH
• ANALYSIS OF DATA REGARDING THE SALE OF TICKETS
• PROBLEM IDENTIFICATION
• THE FOCUS FOR THE DESIGN
• METHODOLOGY FOR THE DESIGN.
• AREA & PASSENGER DENSITY ANALYSIS OF THE EXISTING COACH
• ERGONOMIC DATA^* TO BE USED IN THE DESIGN OF THE FURNITURE AND ITS JUSTIFICATION.
• BODY WEIGHT TRANSFERRED ON THE HEELS UNDER VARIOUS HEIGHTS OF SUPPORTS

The old coaches were made out of wood paneling and frames. With the advent of new technology and excessive loads the present coaches are made of steel fabrication. The frame is strengthened by partitions in the coach between the doors and the seat acting as bulk heads for stability and rigidity of the coach. The internal lining is done on the steel sections or Aluminum transport sections. Filler board or asbestos sheet is used for ceilings. Laminates are used in the side paneling.

The windows have two vertical sliding shutters with one in aluminum louvers and the other is glazed with aluminum frame. The doors are sliding type. It is either die cast in Aluminum or fabricated.The other accessories are Fluorescent lights, fans and air vents at the top. The seats are made of hot pressed wood laminate on a supporting structure of MS steel pipes. Shelves are provided at the side walls at 1.9m for keeping the luggage. For standee's hand grips are provide for support that are made of MS flats and/or wood handle.

ANALYSIS OF DATA REGARDING THE SALE OF TICKETS

Data regarding the sales of the ticket was provided by the railway from Mar 96 to April 97. The data include the sales of the following types of ticket: (Derived from Yogesh D. report)

1. Season tickets
2. One way tickets
3. The average daily sale of one way and two way tickets.

1. The maximum number of tickets sold from any station are for CST due to its location and land use pattern.
2. The stations which are second largest on this list doesn't require a travel of more than 1 to 1:30 hr.
3. Stations that are near Kalyan have maximum travel towards Dadar & Mulund, which is again within the range of an hour.
4. The passengers traveling from Mulund are drastically low which suggest that bus transport facilities also affect the rail travel.
5. The average time taken by people to travel is 45 min to an hour one way.
6. The table shows that the people traveling between Thane and CST are maximum.

PROBLEM IDENTIFICATION

The analysis can be concluded in terms of the following areas seeking immediate attention in order.

  1. Comfort level.

The comfort level (read discomfort level) can be divide into two basic parts viz. Muscular stress and Thermal stress.

a. Muscular stress-

• The muscular stress is more evident in the standees. Chiefly because, there are no means to support the body except the legs.
• The hand grips allow partial and insufficient respite in transferring the loads.
• Height of the grips causes strain in the neck and the shoulder.

• The number and the position of the fans are inadequate.
• Overcrowding leads to excessive sweating.
• Vents and the fans are placed closely defeating the purpose.
• Improper inlets and outlets for the air are not responsive to the Bombay climate.
• Absence of vents in the seat causes excessive sweating on the contact areas.

• Support system available for standees wherever available is insufficient or non existent. This leads to confusion and instability when people get in or get out of the train.
• The only support points being feet of an individual lead to high leverage when the push comes on the chest level.
• The pivots in the grips lead to excessive swaying of commuters in unison when the train is on the move.

• The density variation between the standing and the sitting leads to exceptionally high densities in the standee area (10-12 persons/m2) grossly violating the personal space.
• During the peak hours the personal space of the seated is violated due to intrusion of the standees in between the leg space of seated.

• The location of the luggage racks becomes excuse for the standees to intrude the seating area.
• Carrying luggage is a difficult task during the peak hours and the luggage area is not easily accessible from the door area, where the commuters are stuck.
• Holding the grip by one hand and carrying the luggage in the other ( & to protect personal space) prevents a passenger to change body and hand postures, which causes strain.

The low height of the windows does not even permit the third person (under normal posture) on the seat to view the Station name signage outside

• The problem is more for a person standing inside on the gangway.
• There is a lack of information on ‘what station’ and ‘which side of train' the station will come. This causes confusion amongst the infrequent passengers and also leads them to stand near the door.

• The interior details are not designed to be vandal proof. The materials used inside have an alternate usage and vandals can utilize them for some other purposes or can sell it as scrap.
• The treatment on the walls is susceptible to graffiti and defacing.

 

 
 
 
 
 

Physiological comfort, Stability, Personal space

• Semi standee area and semi standing seat
• Seating area and the seats
• Hand grips, stability aids
• Partitions

• Window
• Ventilation design
• Shutters

• Baggage holds & racks

• Signage
• Illumination
• Color Scheme
• Alarm Chains
• Switches
• Communication System

• Material
• Detailing

It is not denied that ventilation holds a great deal of importance in the whole comfort system. But ventilation design is a specialized field by itself (out of the purview of Industrial design) and work is already done by Aerospace Department, IIT Bombay. The change in the layout has been, as discussed earlier, is suggested by Yogesh Dandekar (see appendix 1 for details). It calls for an immediate attention to detail the furniture and fixtures to let all the work done work in synergy.

The list & scope boils down to "Design and detailing of the seating and the specially allocated standing area". Most of the problems faced by the seated commuters can be solved by simple solutions like elevating the seats, reducing the dimensions and providing vents. What need grave attention is the semi-standing area, which was never provided, designed or detailed. It seems thoroughly ironical as maximum commuters travel standing. A great need was felt to give the primary design attention to this area. This led to redefining the focus of the project to "Design and detailing of body support system in the specially allocated standing area".
 

METHODOLOGY FOR THE DESIGN.

The unique situation of the Bombay locals called for unconventional solution. There was a need to generate data to meet these extreme requirements. The factors considered unique to this problems were as follows
 
 

• Selection of suitable ergonomic dimensions to adapt to the varying percentile.
• Optimization of height of the support system for maximum comfort possible.
• Width and length of support to achieve required densities and maximum comfort.
• Configuration of supports to establish flexible postures.
• Densities to be achieved in the aforesaid area and maintain contextual standards of comfort and personal space.
• Personal space and its protection.
• How commuters will align themselves for maximum support and to protect their personal space in the peak hours and lean hours?

  This was extracted from

• Experimentation
• Simulation of these spaces and crowd
• Observing existing situations as to how people adjust for comfort and personal space in situations which are

1. Contextual, i.e. prolonged hours in crowded situation like locals, buses, rallies, etc.
2. Peripheral situations, i.e. Bus stops, railings, classes, cafeterias, etc.

The coach area of the existing II class compartment in the trailer coach:

11.062 x 3.506 = 38.78 m² (53% of trailer coach)
 

Seating Areas:

2 (columns)x 8 (rows) x {.5x 1.45} (seat area) + 2 x {0.5x3.506} (end seats) = 15.106 m²

Area between facing seats:

6 x (1.45 x .5675) (facing bays)+ 2 x (3.506x .5675) (end seats) =8.91m²

  Net area left for standees in the aisles and gangways:

  38.78 – 24.046 = 14.764 m²

As per Railway estimates a nine coach rake brings in 4000 – 5000 people in the peak hours, which when distributed uniformly gives a density of 450- 500 people / coach. This gives the number of persons and the densities in the II class area in a trailer coach is shown in the table below
 
 
 

Density	450/ coach	500/ coach	550/ coach	600/ coach
Passengers in the aforesaid area.	238	265		318
Seated #	100	100	100	100
Area	24.05	24.05	24.05	24.05
Density	4.16	4.16	4.16	4.16
Standees*	130	165	191	218
Area	14.68	14.68	14.68	14.68
Density	9.35	11.18	12.94	14.77

Densities in persons/m²
 

#The seated refers to the persons in the seating area i.e.

62 fully supported on the seats.

16 partially supported on the seats.

30 standing between the legs of the seated passengers.

Total = 62+0.5 x 16 + 30 =100

*The standees referred here in this table is exclusive of the people standing between the seats and the fourth person on the seat. Alternatively they are the persons with minimum comfort. The above data when cross checked with those on the train gives us a peak hour standee density of 10 – 12 persons/m²
 

The density clearly suggest the two extremes . The seated people enjoys a density of 4.48 people/m², while the standees have to suffer a density more than double of the former. The seating areas occupy 63 % of the floor space while the passenger they accommodates is only 40% to 45% during the peak hours. Contrary to that the circulation areas which is 37 % of the floor area accommodates 55% - 60% of the passengers during the peak hours.
 

The standee areas must be so designed that it gets a fair share of the total coach area. The target was kept to achieve a standing space 200% of the seating capacity area. That leads to a figure of 19 -20 passengers in the semi standing position in the same area as the facing seats occupy. The areas must be distributed accordingly to accommodate standees. Also the fixtures must flexible enough to accommodate a more comfortable posture on the same during lean hours.

ERGONOMIC DATA^* TO BE USED IN THE DESIGN OF THE FURNITURE AND ITS JUSTIFICATION.
 
 
 

Attribute	Percentile  to be used	Justification	Value
Weight	95	To bear maximum weight	80.0 kg
Stature	95	To accommodate tallest person	175.0 cm existing height is 250
Buttock height	5	As a taller person can lean comfortably at the same height.	78.2 cm
Crotch height	5	As 95%% can bend his knees while resting on such a support	70.3 cm
Overhead grasp	5	To enable shortest person to reach the racks or grip	187.7 cm , aim to provide flexible grip
Sitting Height (relaxed)	95	To enable head clearance for the 95%%	86.1 cm
Sitting height	95	To enable head clearance for the 95%%	90.0 cm
Mid shoulder sitting Height	95	To enable shoulder clearance for the 95%%	61.8 cm
Elbow rest height	95	To avoid strain on the shoulders by providing lesser height	26.0 cm
Thigh clearances	95	To accommodate thicker thighs	15.3 cm
Popleteal Height	50	To avoid numbness in the lower legs , footrests for 5%%	43.2 cm ( 40.0 for the 5%%)
Knee height	95	For knee & lower leg clearances	55.2 cm
Buttock Popleteal length (sitting)	5	As taller person can rest the thighs on 5%% dimension	40.9 cm
Buttock knee length	95	For clearances for taller persons	59.1 cm
Bidetoid breadth sitting	50	As in the context the 95%% can lean and adjust to the 50%%	45.4 cm
Hip Breadth (sitting)	95	To avoid numbness in the hip	35.3 cm

*Data Source is National Ergonomic Data Base for Indian Male population- a pilot study, draft report, Oct. 1992, IDC, IIT Bombay

BODY WEIGHT TRANSFERRED ON THE HEELS UNDER VARIOUS HEIGHTS OF SUPPORTS

In order to substantiate the logic of semi standing or leaning and also to arrive on suitable height of the support a small experiment was conducted.

The subject was allowed to lean against at varying level of supports in a posture of his own choice. The distance of the tips of the toes was fixed at 50 cm from the center of the support. A weighing scale was placed under the feet of the subject to observe the weight transferred on the legs.

It was observed that when the level of support reaches the 47%– 37% of the stature, there is a drastic difference in the fraction of the weight transferred on to the legs. Around 37 % it is the minimum for a subject. The sample data can be seen in the table below
 
 
 

Ht. of the support cm	Brief description of the posture	Weight. on legs	Remarks
W/o support	Standing vertically on both the legs	84	Normal wt.
150	Elbows & back resting on the support	70	14 kg on the elbows.
150	Forearms & head on the support	74	10 kg on the forearms
140	Elbows & back resting on the support	74	14 kg on the elbows.
140	Forearms & head on the support	70	10 kg on the forearms
130	Elbows & back resting on the support	74	14 kg on the elbows.
130	Forearms & head on the support	70	10 kg on the forearms
120	Elbows & back resting on the support	74	14 kg on the elbows.
120	Forearms & head on the support	65	19 kg on the forearms
110	Elbows & back resting on the support	75	09 kg on the elbows.
110	Forearms & head on the support	65	19 kg on the forearms
100	Elbows & back resting on the support	65	19 kg on the elbows.
100	Forearms & head on the support	50	24 kg on the forearms
90	Hips supported on the bar	65	19 kg on the hips
90	Hips & palms supported on the bar	50	34 kg on the palms & hips
80	Hips supported & leaning forward	35	49 kg on the hips
80	Hips supported & leaning backward	20	64 kg on the hips
70	Hips supported & leaning forward	22	62 kg on the hips
70	Hips supported & leaning backward	10	74 kg on the hips
At Crotch	Siting vert. with legs on either side	45	39 kg on the hips and crotch