Vehicle having independently driven and controlled right and left drive wheels

A self-propelled vehicle comprising:

• a vehicle body;
• a maneuvering unit mounted on the vehicle body and operated by a driver aboard on the vehicle body;
• a control unit for generating a control amount for changing a travel speed and a travel direction of the vehicle, based on an operational amount of the maneuvering unit;
• a pair of left and right freely steerable caster wheels;
• a drive unit including a first drive section and a second drive section which are driven and controlled independently of each other by said control amount;
• a drive wheel unit including a left drive wheel driven for traveling by the first drive section and a right drive wheel driven for traveling by the second drive section, the travel direction being changed by a rotation difference between the left drive wheel and the right drive wheel;
• a bank detector for detecting a degree of bank of the vehicle and outputting it to said control unit;
• and
• a caster wheel drive section for driving the caster wheel for traveling;
• wherein said control unit includes:
• a drive torque calculation section for calculating drive torque required for said first drive section and said second drive section;
• a compensation torque calculation section for calculating a compensation torque for resolving a travel direction difference between a target travel direction and an actual travel direction in a bank travel, for said first drive section and said second drive section based on said bank degree;
• a correction section for correcting said control amount based on said required drive torque and said compensation torque;
• and
• a caster wheel control section, wherein said caster wheel control section generates a caster wheel rotation control command based on said degree of bank:
• θ (=roll angle) during the bank-traversing of the vehicle, and wherein said caster wheel drive section outputs a caster driving torque:
• Z=F(θ) based on said caster wheel rotation control command so as to cancel out an inclinedly downwardly turning tendency occurring on the caster wheel.

A self-propelled vehicle comprising:

• a vehicle body;
• a maneuvering unit mounted on the vehicle body and operated by a driver aboard on the vehicle body;
• a drive unit including a first drive section and a second drive section which are driven and controlled independently of each other by respective drive wheel control commands;
• a drive wheel unit including a left drive wheel driven for traveling by the first drive section and a right drive wheel driven for traveling by the second drive section;
• a pair of left and right caster wheels which is controlled in a steering angle thereof by a caster wheel control command;
• a bank detector for detecting a degree of bank of the vehicle;
• a caster wheel drive section for driving the caster wheel for traveling;
• and
• a control unit including a drive wheel control section for generating said drive wheel control commands based on an operational amount of the maneuvering unit, said control unit further including a caster wheel control section, wherein said caster wheel control section generates a caster wheel rotation control command based on said degree of bank:
• θ (=roll angle) during the bank-traversing of the vehicle, and wherein said caster wheel drive section outputs a caster driving torque:
• Z=F(θ) based on said caster wheel rotation control command so as to cancel out an inclinedly downwardly turning tendency occurring on the caster wheel.