초록

A power-assist vehicle such as a wheelchair senses driving torque/force applied by a user through a transmission. The detected force/torque is utilized in a control system with a control map defining a desired dynamic of the vehicle and programmed with the desired mass and drag parameter.

대표청구항 ▼

1. A wheelchair comprising:first and second drive wheels each having an axis and a coaxial handrim for receiving a driving torque from a user;each drive wheel being coupled to a motor; anda control system programmed with at least one control map defining a desired dynamic of the wheelchair and progr

1. A wheelchair comprising:first and second drive wheels each having an axis and a coaxial handrim for receiving a driving torque from a user;each drive wheel being coupled to a motor; anda control system programmed with at least one control map defining a desired dynamic of the wheelchair and programmed with a desired mass parameter and a desired drag parameter, the control system utilizing said control map and measured values of said driving torque from said user and an actual velocity to determine a desired velocity and control the motor to reduce an error component between said actual velocity and said desired velocity. 2. The wheelchair of claim 1 wherein said drag parameter comprises a coulomb damping parameter. 3. The wheelchair of claim 1 wherein said drag parameter further includes a linear damping parameter. 4. The wheelchair of claim 1 wherein said desired velocity is produced in response to an iterative integration of:measured handrim torque multiplied by a first constant;the negative of the desired velocity multiplied by a second constant; andthe negative of the sign of the desired velocity multiplied by a third constant. 5. A power assist vehicle comprising:a drive wheel;input means for receiving a driving torque from a user;a motor; anda control system programmed with at least one control map defining a desired dynamic of the vehicle and programmed with a desired mass parameter and a desired drag parameter, the control system utilizing said control map and measured values of said driving torque from said user and an actual velocity to determine a desired velocity and employs a single-axis velocity servo loop to control the motor to reduce an error compound between said actual velocity and said desired velocity. 6. The wheelchair of claim 5 wherein said desired velocity is produced in response to an iterative integration of:measured user-applied torque multiplied by a first constant; andthe negative of the sign of the desired velocity multiplied by a second constant. 7. The wheelchair of claim 5 wherein said desired velocity is produced in response to an iterative integration of:measured user-applied torque multiplied by a fist constant; anda damping effect provided by a function of the desired velocity.