20.6Other Physical Characteristics
Whatever good things we build end up building us.Jim Rohn, businessman, 1930–2009
Besides the vehicle length and propulsion system type, there are a range of other characteristics that will define the vehicle. The specifications set forth during the operational design will determine many other additional factors regarding the technical specification required for the vehicle, including the following:
- Body type (segregated from chassis, unified);
- Number of doorways and size of doorways;
- Type of system for opening and closing the doorways;
- Doorway location;
- Transmission type (automatic, manual, retarder);
- Type of propulsion system;
- Engine location (front, center, rear);
- Engine power rating;
- Acceleration capacity;
- Braking technology;
- Braking capacity;
- Suspension type (springs, hydraulic);
- Road turning radius (internal and external);
- Axle-load capacity.
If decisions on these parameters are made without reference to the operational design, serious design mistakes can occur. For example, in Jakarta, Indonesia, a vehicle with plenty of capacity was procured, but the vehicle had only one door. This single-door decision seriously delayed customer boarding and alighting speed, and the entire capacity of the corridor was severely compromised. Similarly, vehicles with axle loads above the weight-bearing capacity of the road surface treatment on the corridor led to rapid deterioration of the roadbed.
Table 20.8Specifications from the Mexico City Manual on Safety, Accessibility, Comfort, and Manufacturing of Buses.
* Recommended for medium and steep routes because of the engine type and location.
** Recommended for flat routes because of its engine type and location.
In most countries, there are regulations and conditions that public transportation vehicles must meet pertaining to bus import, assembly, and manufacturing. Identifying all conditions and restrictions thus becomes necessary, along with any required certification and standardization processes. Norms, standards, and regulations that cover the following fields are present in most countries:
- Environmental performance;
- Security standards;
- Physical conditions;
- Country of origin;
- Local manufacturing ratios;
- Import procedures and requirements;
- Tariffs and other import duties;
- Handicap accessibility.
In the absence of laws and regulations governing these issues, setting the vehicle technical specification should take these issues into consideration in any case, following international norms.
As a reference, Table 20.8 is a summary of the vehicle specifications put forward by the public company overseeing Phase I of the Bogotá TransMilenio system in 2000. The actual specifications for any given city will vary depending on local preferences and circumstances.
Table 20.9Bogotá Vehicle Specifications (Trunk Vehicles)
| Vehicle attribute | Specification |
|---|---|
| Load weights | |
| GAWR front axle load | 7,500 kg |
| GAWR middle axle load | 20,500 kg |
| GAWR rear axle load | 20,500 kg |
| GVWR total weight | 30,000 kg |
| External dimensions | |
| Maximum width | 2.60 meters |
| Maximum height | 4.10 meters |
| Overall minimum length | 17.50 meters |
| Overall maximum length | 18.50 meters |
| Maximum front overhang | 3000 mm |
| Maximum rear overhang | 3500 mm |
| Floor height from ground | |
| Minimum height | 870 mm |
| Maximum height | 930 mm |
| Turning radius | |
| Minimum between sidewalks | 7,400 mm |
| Maximum between sidewalks | 20,100 mm |
| Minimum between walls | 7,400 mm |
| Maximum between walls | 13,400 mm |
| Chassis and body | |
| Body type | Integral body or self-supporting body |
| Modification | Every modification of the chassis must be formally approved by the manufacturer |
| Certification of static load proof | Can be obtained by physical proof or computational model; Minimum certified roof resistance in 5 minutes: 50% of GMV; Maximum deformation in every point: 70 mm; |
| Customer space | |
| Total customer capacity | 160 customers |
| Seating capacity | 48 customers |
| Color of seats | Red |
| Number of preferential seats | 6 |
| Color of preferential seats | Blue |
| Standing customer area | 16 m2 |
| Standing design capacity | 7 customers per square meter |
| Wheelchair capacity | 1 space for wheelchair (90 centimeters x 140 centimeters); Located in the first body of the bus in front of the second door |
| Layout of seats | 2-2, 2-1, 1-1, 1-0; Perimeter or front-to-front |
| Internal dimensions | |
| Free internal height | 2100 mm minimum |
| Superior visibility height | 1850 mm minimum |
| Inferior visibility height | 600 mm minimum; 850 mm maximum |
| Corridor width | 600 mm minimum |
| Seating characteristics | |
| Characteristics | Individual seats; Closed in back; Direct anchorage to the vehicle floor; Without upholstery or cushioned; Without sharp edges or rivets; |
| Materials | Plastic; Washable; Self-extinguishing and flame retardant; No release of toxic gases during combustion; |
| Seat dimensions | |
| Distance between seats | 700 mm |
| Distance between seats front to front | 1300 mm |
| Seat depth | 350 mm minimum; 430 mm maximum |
| Seat height (measured from floor) | 350 mm minimum; 450 mm maximum |
| Back height | 500 mm minimum; 600 mm maximum |
| Seat width | 400 mm |
| Handles and handrails | |
| Characteristics | Surfaces without sharp edges; End finished in a curve; Continuous; Non-slip surface; |
| Dimensions | Diameter: Between 30 and 45 mm; Horizontal handrail height: 1750 mm minimum and 1800 mm maximum; Distance between vertical balusters: 1500 mm or every two seats; |
| Windows | |
| Front window type | Laminated |
| Type, all other windows | Tempered |
| Color of window | Green |
| Transparency level | 70% |
| Advertising | Windows without advertisement |
| Inferior module | Fixed to the body with adhesive |
| Superior module height | Minimum: 30% of total height of the window; Maximum: 50% of total height of the window; |
| Doorways | |
| Number of customer doorways | 4 |
| Position | Left side of vehicle |
| Minimum free width | 1100 mm |
| Free height | 1900 mm |
| Door opening time | 2 seconds |
| Emergency doors | Type: single door; Number of emergency doorways: 2; Minimum free width: 650 mm; Free height: 1800 mm; With stairs covered and with a pneumatic opening system; |
| Control and instrumentation | |
| Logic unit | Communication display in view of driver; GPS and communications antennas; Tachnograph (with register and storage of instant velocity, distance traveled, times of operation and non-operation over 24-hour period); |
| Control center communications | Voice communication equipment |
| Instrumentation | Odometer with pulse output connected to the logic unit |
| Complete instrumentation with alarms for low pressure of the air brake system and motor oil system | |
| Ventilation | |
| Air renewal requirement | Minimum 20 times per hour |
| Noise | |
| Maximum internal sound level | 90 dB(A) |
| Destination signs | |
| Number and size of signs | 1 in front: 1950 mm x 300 mm; 2 on left side: 450 mm x 250 mm; |
| Visibility | Visible from a distance of 100 meters |
| Technical standards | |
| Vehicle | NTC 4901-1 Mass Transport Passenger Vehicles |
| Test methods | NTC 4901-2 Mass Transport Passenger Vehicles |
| Local standards | ICONTEC (Colombian Technical and Standardization Institute) |
Source: TransMilenio SA