1. Tóm tắt
1.1. backdriveable modular actuators enable high-bandwidth force control, high force density, robustness to impacts
1.2. high-bandwidth force control (cho phép kiểm soát lực băng thông cao)
1.3. high force density (mật dộ lực cao)
1.4. 0.3 m tall and weighing 9 kg (cao 0.3 nặng 9kg)
1.5. dynamic trot, trot-run, bounding, and pronking gaits on the robot to speeds of up to 2.45 meters per second (các dáng đi ... tốc độ 2.45 m/s) robot to execute 360◦ backflips (ngoài ra còn có thể nhào lọn 360 độ)
2. III. BỘ TRUYỀN ĐỘNG MÔ-ĐUN
2.1. using a high torque density electric motor coupled to a low-ratio transmission to achieve high torque density
2.2. back drive ablility, and high bandwidth force control: [8] "Design principles for energy-efficient legged locomotion and implementation on the MIT cheetah robot”
2.3. "Proprioceptive Actuator Design in the MIT Cheetah: Impact Mitigation and High-Bandwidth Physical Interaction for Dynamic Legged Robots"
2.3.1. Three different EM actuator concepts
2.3.1.1. High-ratio geared motor with torque sensor
2.3.1.1.1. geared motor with force/ torque sensor
2.3.1.1.2. High gear Ratio Transmission
2.3.1.1.3. stiff sensor
2.3.1.1.4. leg
2.3.1.2. SEA
2.3.1.2.1. Series Elastic Actuator
2.3.1.2.2. High gear Ratio Transmission
2.3.1.2.3. Spring, Encoder
2.3.1.2.4. Leg
2.3.1.3. proprioceptive force control actuator (bộ truyền động điều khiển lực độc quyền)
2.3.1.3.1. High torque density motor
2.3.1.3.2. Low Gear Ratio Transmission
2.3.1.3.3. Low inertia leg
2.4. A. Thiết kế
2.4.1. integrated with a 6:1 single-stage planetary gear reduction
2.4.2. built-in position sensor
2.4.3. iFlight ex-8
2.4.3.1. large airgap radius 40.5 mm
2.4.3.2. stack length of 8.2 mm
2.4.3.3. a large number of pole-pairs
2.4.4. To minimize the axial length of the actuator (cơ cấu chấp hành)
2.4.4.1. the planetary gear set is placed inside the center of the stator
2.4.4.2. roughly 0.3◦ of backlash at the output.
2.4.5. 24V, 30A and 40A peak
2.4.6. receives torque, position, velocity and gain commands
2.4.7. returns position, velocity, and estimated torque
2.5. B. Thiết kế cho Tác động
2.5.1. Học tăng cường điều khiển momen xoắn
2.6. C. Hiệu suất
2.6.1. Mass 440g Dimensions 96 mm O.D., 40 mm axial length Maximum Torque 17 N m Continuous Torque 6.9 N m Maximum Output Speed 40 rad/s@24 volts Maximum Output Power +250/ − 680watts Current Control Bandwidth 4.5kHz@4.5N m, 1.5kHz@17N m Output Inertia 0.0023 kg m2
3. IV. THÍ NGHIỆM
3.1. the quadratic program (QP) based balance control
3.2. the convex Model Predictive Controller (cMPC)
3.3. A. Vận động
3.3.1. Convex Model Predictive Control (cMPC)
3.3.1.1. trotting at up to 2.45 m s−
3.3.1.2. strafing sideways at 1.0 m s−
3.3.1.3. yawing at a rate of 4.6 rad s−1
3.3.1.4. linear accelerations of up to 5 m s−2
3.3.2. 5 ms
3.3.3. No filtering or further smoothing is applied to the resulting torques
3.4. B. Lộn ngược
3.4.1. 1) Backflip Trajectory Optimization
3.4.2. 2) Backflip Control
4. I. GIỚI THIỆU
4.1. Super Mini Cheetah
4.2. Minitaur
4.3. Cheetah Cub
4.4. Little Dog from Boston Dynamics
4.5. MIT Cheetah 3
4.6. ANYmal
5. II. THIẾT KẾ
5.1. 0.21 m upper, 0.19 m lower and 0.38 m between the front and back legs.
5.2. A. Bộ truyền động mô-đun
5.2.1. uses identical modular actuators (sử dụng các bộ truyền động modun giống hệt nhau)
5.3. B. Thiết kế cơ khí
5.3.1. abduction/adduction (ab/ad) joint can rotate ± 120◦
5.3.2. the hip joint ± 270◦ (limited by wire length)
5.3.3. the knee joint ± 155◦
5.3.4. each leg is producing peak 150 N (1.7 bodyweights)
5.3.5. continuous vertical force over 60 N (0.7 bodyweights)
5.3.6. The legs have an angular acceleration capability of 1700 rad s−2 at the hip and ab/ad joints, and 5000 rad s−2 at the knee joint.
5.3.7. This corresponds to a linear acceleration of 875 m s−2, or 89 G’s, at the foot using only the knee motor.
5.4. C. Điện tử và Máy tính
5.4.1. quad-core Intel Atom CPU and 4 GB RAM
5.4.2. communicates with the 12 actuators through a CAN bus
5.4.3. actuator communication loops run at 1 kHz
5.4.4. powered by an off-the-shelf 24 V, 120W h Li-Ion battery
5.4.5. DC-DC converter down the battery voltage and provide electrical isolation between the power electronics and computer