Based on the different fields of application Multidirectional CLAAS Drive, in short MC-Drive, has been developed. This highly flexible vehicle- and aerial work platform system is used for transporting aeroplane parts, for loading and unloading of machine tools or for assembling different aeroplane components such as engines.
The units shown in figures 1 to 3 are part of the MC-Drive pro-duct portfolio.
MC-Drive TP 200 (figure 1) is at the Airbus plant in Finken-werker in Hamburg and is used for in-plant transport of different components like component carriers and transport cradles or, as shown in the picture, fuselage section transporters.
MC-Drive TP 60 (figure2) is used for in-plant transport of engine tools in Riverside, USA (near Los Angeles), e.g. for loading and unloading of a milling machine with 6 axles.
MC-drive PT 200-WHT (figure 3) is used in the Airbus plant in Broughton, Great Britain, for the transport of wings. Due to the limited space the free movability of the MC-Drive offers enormous productivity benefits and makes moving of the big components much easier.

Figure 2: MC-Drive TP 60

Figure 3: MC- Drive TP200-WHT

MECANUM-Drive
Basis for vertical movability of the MC-Drive vehicles is the MECANUM-wheel (figure 4). The MECANUM-wheel, developed in 1973 by Swedish engineer Bengt Ilon, consists of a rim onto which freely rotating, barrel-shaped rolls are mounted at an angle of 45°. These rolls form an optimal full circle around the wheel circumference.
As every individual wheel is actuated separately in regards to rotational direction and speed with the help of separate electric motors, two force vectors result per wheel. Opposite force vectors of two wheels counterbalance each other while force vectors acting in the same direction are added to form the resulting driving power (figure 5).
The result is mobility in the complete plane. Movement in lengthwise and transverse direction can be combined with circular motion around different points. All movements like straight-ahead driving, sideways driving, cornering or turns are actuated with a 3-axle joystick. Position of the pivot point can be freely selected, depending on the respective requirement. So switching over to a new pivot point is possible even when several vehicles are coupled.
For operation of the MECANUM-wheel fitting of a left-hand wheel and a right-hand wheel on each ›vehicle axle‹ is required.
To ensure constant ground contact of all four wheels even if the ground is uneven, different running carriage may be used. With a passive running carriage the wheels on one side of the vehicle are connected with a coupling rod. With this three-point bearing the system is supported in a mechanically fixed way.
With an active running carriage the same ground forces are generated at the individual wheel suspensions. These running carriages are either driven hydraulically or with spindles. Additionally, lifting functions or spring suspension can be realized with active running carriage.
Aside from the manually controlled drive mode with joystick, automatic operation is optionally possible as well. For driving or positioning, the different navigation systems like laser scanner, inductive or optical track guiding, positioning scanner etc. are applicable.

Figure 4: MECANUM–wheel

Figure 5: Force distribution in MECANUM wheels depending of the drive direction

Project X-Lift 10ex
A special project of the CFT in the Aerospace field has been achieved for a Russian aircraft builder. The previous production program of this aircraft manufacturer mostly concentrated on the development and production of fighter jets. It has currently been supplemented by a civil aeroplane. The aeroplane is approximately 30 meters long with a wingspan of 28 meters and a capacity of up to 100 seats, depending on the configuration. Due to the considerably larger dimensions the painting plant had to be adjusted accordingly. Since September 2009 the manufacturer has used the explosion-protected aerial work platform X-Lift 10ex, which has been developed by Claas (CFT). With a completely extended platform height of 9 meters even the tail unit of the plane (ca. 10.3 meters) can be easily reached. With the transverse and lengthwise extension of the platform the wings and the upper fuselage segments can be reached as well (figure 6).
Furthermore, this aerial work platform has compulsory safety devices according to EN 280, like monitoring of tilting, speed, temperature of the individual components, lowering stop, etc. 
If the platform is retracted and loaded to the maximum limit of 1,000 kg, speed of up to 1 m/s is infinitely adjustable. With an extended shank lifting capacity amounts to 350 kg, which is approximately 2 people plus 200 kg of additional load. Because of the required tilt resistance the maximum movement speed is significantly lower when the shank is extended.
Furthermore, the aerial work platform is equipped with circumferential safety bumpers to prevent damaging of the surface of the aeroplane with the X-Lift 10ex. In case of collision these padded elements block further movement with an integrated switching contact and the operator can activate the work platform only by pressing an additional ›affirmation button‹.

Explosion protection
The aerial work platform for use in Zone 1 is explosion protected in category II 2G (equal to EPL b), explosion group II A, and temperature class T4 as vapours may be generated during painting which may cause a potentially explosive atmosphere. Here company R. STAHL Schaltgeräte GmbH made important contributions towards this, to realize the concept for the drive mechanism, for operation and safety according to the requirements explosion protection. For control of the different axles DC drive controls are used which generate quite a lot of heat lost during operation. That is why these components have been fit into two enclosures series CUBEx and been coupled via a terminal box. This distributed arrangement makes sure that the necessary heat dissipation occurs via the enclosure walls (figure 7). The indication elements of the battery electronics can be checked any time through the window in the front door.
Design and connection of the joystick and the safety bumpers had to be adjusted to use in explosive atmosphere as well. Thus the circuits have been designed in type of protection intrinsic safety ›i‹. All electrical components are connected in the CUBEx enclosures. The main circuit components are connected to the outer supplies via direct entries. For connection of the control circuits the terminal box positioned in the middle is used.

Figure 6: Explosion protected aerial work platform MC-Drive X-Lift 10 ex

Figure 7: Aerial work platform Mc-Drive X-Lift-10 ex with two flameproof enclosures series CUBEX with built in control system coupled via a terminal box