Post by Admin on Jan 3, 2016 5:15:59 GMT
Matthieu Lapeyre of Flowers Lab embarked on The Poppy Project in 2012. An open-source (s/w & h/w), 3d printable humanoid, standing at 84cm tall Poppy is around twice the height a typical humanoid.
With a little investigation into The Poppy Project it becomes apparent that Poppy is still unable to walk without the aid of a person leading it by the hands. Although it is easy in such cases to think "failed to walk after 3 years?.. Closed-case. NEXT!!!', that would be an altogether shortsighted view to take.
After reading Matthieu Lapeyre's thesis (here: www.matthieu-lapeyre.com/thesis.pdf) it quickly becomes clear that every aspect of Poppy was given extensive consideration from the beginning.
Some of the interesting design choices used in Poppy include;
•An articulated trunk/spine incorporating 5x servo's.
•A Semi-Passive spring loaded knee.
•Each foot utilising 2x passive joints (torsion sprung). One for the toes permitting a humanlike toe-heel gait, and the other on the ankle roll plane allowing the foot to naturally & passively adjust to uneven terrain.
One thing that does become readily apparent when reviewing case-studies such as these, are any major disparities between numbers in comparison to other reviewed case-studies, especially where unaided bipedalism had been successfully achieved.
'Case-in-point', in this instance the figures would suggest that with total servo weight accounting for over half the total weight, its perhaps overladen (& arguably over-powered) with heavy actuators.
There is undoubtably a wealth of information & detail to be obtained from reading Matthieu's Poppy thesis and a worthwhile read for anyone with a keen interest in bipedal kinematics.
Overall Height: 840mm
Overall Width (arms ext): 933mm
Leg Length: 413mm
Foot Width: 50mm
Total Weight: 3.5kg
Dynamixal Servo's used;
MX-28/Weight-72g/qty-21
MX-64/Weight-126g/qty-4
Hips- MX-64/qty-2 & MX-28/qty-4
Knees- MX-28/qty-2
Ankles- MX-28/qty-2
Trunk-MX-64/qty-2 & MX-28/qty-3
Shoulders- MX-28/qty-4
Arms- MX-28/qty-4
Neck/Head- MX-28/qty-2
TOTAL MX-28's: 21 (£3112.62p)
TOTAL MX-64's: 4 (£809.46p)
Total Servo Cost: £3922.08p
MX-28 Stall Torque (each): 3.1Nm (@14.8V) [Weight (each): 72g]
No Load Speed (RPM): 67
MX-64 Stall Torque (each): 7.3Nm (@14.8V) [Weight (each): 126g]
No Load Speed (RPM): 78
Leg Servo's: Dynamixel MX-28 (RS485 Asynchronous Serial)
1% (0.031Nm) leg servo torque per 1% (35g) overall body weight
MX-28 Dims: W35.6xH50.5xD35.5
Leg Servo Weight (each): 72g
Number of Leg Servo's: 10
Leg Servo (x10) Weight: 0.72kg
Arms/Shoulders Servo (x8) Weight: 0.576kg (3.1Nm each)
Neck/Head Servo (x2) Weight: 0.144kg (3.1Nm each)
Trunk/Torso Servo (x2/x3) Weight: 0.252kg/0.216kg (7.3Nm/3.1Nm)
Total Servo Quantity: 25
Total Servo Weight: 1.91kg
Servo's accountable weight: 54.5%
Leg Servo Rpm: 67 (@14.8V)
Lower body weight: Unknown
With a little investigation into The Poppy Project it becomes apparent that Poppy is still unable to walk without the aid of a person leading it by the hands. Although it is easy in such cases to think "failed to walk after 3 years?.. Closed-case. NEXT!!!', that would be an altogether shortsighted view to take.
After reading Matthieu Lapeyre's thesis (here: www.matthieu-lapeyre.com/thesis.pdf) it quickly becomes clear that every aspect of Poppy was given extensive consideration from the beginning.
Some of the interesting design choices used in Poppy include;
•An articulated trunk/spine incorporating 5x servo's.
•A Semi-Passive spring loaded knee.
•Each foot utilising 2x passive joints (torsion sprung). One for the toes permitting a humanlike toe-heel gait, and the other on the ankle roll plane allowing the foot to naturally & passively adjust to uneven terrain.
One thing that does become readily apparent when reviewing case-studies such as these, are any major disparities between numbers in comparison to other reviewed case-studies, especially where unaided bipedalism had been successfully achieved.
'Case-in-point', in this instance the figures would suggest that with total servo weight accounting for over half the total weight, its perhaps overladen (& arguably over-powered) with heavy actuators.
There is undoubtably a wealth of information & detail to be obtained from reading Matthieu's Poppy thesis and a worthwhile read for anyone with a keen interest in bipedal kinematics.
Overall Height: 840mm
Overall Width (arms ext): 933mm
Leg Length: 413mm
Foot Width: 50mm
Total Weight: 3.5kg
Dynamixal Servo's used;
MX-28/Weight-72g/qty-21
MX-64/Weight-126g/qty-4
Hips- MX-64/qty-2 & MX-28/qty-4
Knees- MX-28/qty-2
Ankles- MX-28/qty-2
Trunk-MX-64/qty-2 & MX-28/qty-3
Shoulders- MX-28/qty-4
Arms- MX-28/qty-4
Neck/Head- MX-28/qty-2
TOTAL MX-28's: 21 (£3112.62p)
TOTAL MX-64's: 4 (£809.46p)
Total Servo Cost: £3922.08p
MX-28 Stall Torque (each): 3.1Nm (@14.8V) [Weight (each): 72g]
No Load Speed (RPM): 67
MX-64 Stall Torque (each): 7.3Nm (@14.8V) [Weight (each): 126g]
No Load Speed (RPM): 78
Leg Servo's: Dynamixel MX-28 (RS485 Asynchronous Serial)
1% (0.031Nm) leg servo torque per 1% (35g) overall body weight
MX-28 Dims: W35.6xH50.5xD35.5
Leg Servo Weight (each): 72g
Number of Leg Servo's: 10
Leg Servo (x10) Weight: 0.72kg
Arms/Shoulders Servo (x8) Weight: 0.576kg (3.1Nm each)
Neck/Head Servo (x2) Weight: 0.144kg (3.1Nm each)
Trunk/Torso Servo (x2/x3) Weight: 0.252kg/0.216kg (7.3Nm/3.1Nm)
Total Servo Quantity: 25
Total Servo Weight: 1.91kg
Servo's accountable weight: 54.5%
Leg Servo Rpm: 67 (@14.8V)
Lower body weight: Unknown