project specification

HBS-1 Humanoid

The HBS-1 is a humanoid robot used as a platform for research in humanoid robotics, educational and biomedical studies. It is a child-sized robot with anatomically-correct dimensions that closely mimic human motion. The robot has the dimensions and features of a seven-year-old child and is made entirely of 3D printed ABS parts and off the shelf components. All of the structural components (thigh, torso, forearm, etc.) are modular. The DOF, range of motion and torque of each joint enables HBS-1 to sit, stand and perform articulated motion while stationary, as well as pick up and carry objects. All of the mechatronic components, including the microcontrollers, batteries, sensors and actuators, are commercially available products.

Specifications

Height120 cm
Width33 cm
Breadth14 cm
Weight5 kg
Degrees of freedom51
Legs4 DOF per leg
Waist2 DOF
Arms4 DOF per arm
Hands15 DOF per hand
Head3 DOF
Manufacturing method3D printing
MaterialABS

Overview

The HBS-1 is a humanoid robot used as a platform for research in humanoid robotics, educational and biomedical studies. It is a child-sized robot with anatomically-correct dimensions that closely mimic human motion. The robot has the dimensions and features of a seven-year-old child and is made entirely of 3D printed ABS parts and off the shelf components. 

All of the structural components (thigh, torso, forearm, etc.) are modular. The DOF, range of motion and torque of each joint enables HBS-1 to sit, stand and perform articulated motion while stationary, as well as pick up and carry objects. All of the mechatronic components, including the microcontrollers, batteries, sensors and actuators, are commercially available products.

Mechanical system

The robot is powered by a DC power supply connected through wires while tethered.

The head/neck mechanism has 3 DOF: one for neck tilting, one for neck nodding and another for jaw movement. The 3D model of the head was generated from a 3D scan of a doll head.

The arm length of the robot matches the arm length of a seven-year-old boy. Two servos are placed at the shoulder to mimic the human shoulder’s ball joint, another at the elbow and at the wrist. The hand has five fingers, with each with 3 DOF. The fingers are actuated by shape memory alloy (SMA) actuators, which are housed in the forearm. 

The torso is 3D printed, and houses the majority of the electronics. These have detachable sections for quick access to components mounted inside the torso. The 2 DOF waist consists of a roll and a pitch joint with the roll servo mounted at the bottom of the torso and the pitch servo mounted to the top of the pelvis. 

Mechatronic Systems

The robot has 14 Dynamixel servos, four Power HD servos and three Hitec Deluxe servos and shape memory alloy (SMA) actuators as its actuation system. Dynamixel servos have the ability to track the speed, temperature, shaft position and load in real time. They can be controlled by Transistor-transistor logic (TTL), Serial communication (RS485) and controller area network (CAN) communication.

The robot has Firewire stereo cameras in the head. The torso has an orientation sensor, which combines gyroscopes, accelerometers, magnetic sensors and an onboard 32-bit ARM Cortex processor to compute sensor orientation. 

Controllers 

Two servo controllers (Mini Maestro 24-Channel USB Servo and CM-700 Robotis) within the torso drive the 21 servomotors or the robot. The CM-700 Robotis Servo Controller, which communicates with the computer (Intel i7(R) Core (TM) i7-4820k CPU@3.7 GHz with 16 GB RAM and a 64-bit operating system) via the LN-101 USB Downloader, is responsible for the control of the Dynamixel servos. 

The Mini Maestro 24-Channel USB Servo Controller is used to control the Power HD servos and Hitec Deluxe servos. A custom-made controlling circuit is adapted to actuate the fingers using shape memory alloy actuators. The circuit is based on a PIC 8-bit microcontroller that provides a sequence to H-bridge amplifiers, whose outputs are connected to each SMA. The programing of the PIC microcontroller is done using the MPLAB IDE (Integrated Development Environment) board PICDEM™ 2 PLUS. The robot can be programmed through the microcontroller to perform a sequence of instructions to grasp an object in an open loop manner. 

Software

The servo controllers are programmed in Visual Studio using C++. For the implementation of the sequence of actuator movements, the controllers define the sequence using the robot motion controlling code. This enables the robot to have a uniform interface to communicate with two separate servo controllers.

References

Describes the robot, the general design approach of humanoid robots. Describes the design and fabrication of the HBS-1, its modelling and analysis. Goes into the experiments done with the robot, discussions & applications, and the conclusion.

Lianjun Wu, Miles Larkin, Akshay Potnuru, et al. 2015

Wevolver 2022