OpenSim Expert Needed (Long-Term) — Gait & Kicking Simulation Support (IK/ID/SO/CMC, Muscle/EMG/Power)
Budget: $30 – $250 USD
OpenSim Expert Needed (Long-Term) — Gait & Kicking Simulation Support (IK/ID/SO/CMC, Muscle/EMG/Power)
Project Type
Fixed-price • First task in a long-term collaboration (ongoing OpenSim simulation work)
Overview
We are looking for an experienced OpenSim specialist to support a lower-limb musculoskeletal simulation project. This is the first engagement; if collaboration goes well, we will assign recurring tasks of similar scope. Work includes a kicking study with a 2-segment leg model and gait analyses (normal walking & slow running) using a generic neuromusculoskeletal model, with full pipeline: Scale → IK → ID → Static Optimization (SO) → Muscle Analysis → CMC, plus plots and brief discussion.
opensim1-2
Data Provided (organized package)
Kicking: Kicking Problem/legModel2.osim + Kicking Problem/Kicking.mot; compute 4 muscles’ activations & forces (iliopsoas, rectus femoris, hamstrings, vasti) with SO and comment on sequencing & physiological plausibility.
opensim1-2
Gait (walk & slow run): Gait Problem/HW3_reference_model_unscaled.osim with .trc markers & .mot GRFs under Gait Problem/Data; run Scale → IK → ID → SO → Muscle Analysis → CMC. Report over 0–100% gait for key muscles: gluteus maximus/medius, hamstrings, iliopsoas, rectus femoris, vasti, soleus, gastrocnemius.
opensim1-2
Scope of Work
Kicking (SO):
Plot activation(t) & force(t) for the 4 muscles; summarize activation sequence & muscle roles; comment on physiological reasonableness.
opensim1-2
Gait (walk & slow run):
Execute Scale/IK/ID/SO/Muscle Analysis/CMC.
Plot per-muscle forces, moment arms, joint-moment contributions, muscle-tendon power over 0–100% gait.
Compute net joint moments (hip/knee/ankle) and compare vs sum of key muscles’ moments; discuss differences.
Plot neural excitations and make a qualitative EMG comparison; state primary function by phase; identify the most important muscle in stance and swing (walking & running).
Compare SO vs CMC (excitations & forces) and explain differences.
opensim1-2
Muscle grouping rules (must follow):
GMx=glut_max1+2+3; GMe=glut_med1+2+3; Hams=semimem+semiten+bifemlh; Vasti=vas_med+vas_int+vas_lat; Iliopsoas=iliacus+psoas; Gastroc=lat_gas+med_gas.
Do not sum moment arms; sum moments/forces where appropriate.
opensim1-2
Deliverables
Reproducible package: final scaled .osim, setup files for IK/ID/SO/CMC, and resulting .sto/.mot neatly organized by task (kicking/walk/run).
Figures (publication-ready):
Kicking: 4 muscles’ activation(t) & force(t).
Gait (walk & run): per-muscle force / moment arm / joint-moment contribution / muscle-tendon power over 0–100% gait.
Net joint moments vs sum of key muscles’ moments (hip/knee/ankle).
SO vs CMC comparisons (excitations & forces) for representative muscles.
opensim1-2
Short technical note (bullet points OK): activation sequencing & rationale; EMG-style qualitative comparison; net-moment findings; SO vs CMC differences.
Acceptance Criteria / Quality Checks
Pipelines run in OpenSim 4.x without errors; .trc & GRF .mot time axes aligned; filtering choices documented.
Reserve actuators not dominating; results physically plausible.
Clear labels/units/% gait; muscle grouping & “no summing moment arms” strictly followed.
opensim1-2
OpenSim, Biomechanics, Musculoskeletal Modeling, Gait Analysis, Motion Analysis, Static Optimization, Inverse Kinematics, Inverse Dynamics, Computational Modeling, Simulation
Please review the uploaded OpenSim files to understand the task requirements.
If you have experience in similar OpenSim gait or musculoskeletal simulations,
kindly let me know how long you would need to complete this task and how much you would charge,
and include examples or screenshots of your previous related work.
Project Type
Fixed-price • First task in a long-term collaboration (ongoing OpenSim simulation work)
Overview
We are looking for an experienced OpenSim specialist to support a lower-limb musculoskeletal simulation project. This is the first engagement; if collaboration goes well, we will assign recurring tasks of similar scope. Work includes a kicking study with a 2-segment leg model and gait analyses (normal walking & slow running) using a generic neuromusculoskeletal model, with full pipeline: Scale → IK → ID → Static Optimization (SO) → Muscle Analysis → CMC, plus plots and brief discussion.
opensim1-2
Data Provided (organized package)
Kicking: Kicking Problem/legModel2.osim + Kicking Problem/Kicking.mot; compute 4 muscles’ activations & forces (iliopsoas, rectus femoris, hamstrings, vasti) with SO and comment on sequencing & physiological plausibility.
opensim1-2
Gait (walk & slow run): Gait Problem/HW3_reference_model_unscaled.osim with .trc markers & .mot GRFs under Gait Problem/Data; run Scale → IK → ID → SO → Muscle Analysis → CMC. Report over 0–100% gait for key muscles: gluteus maximus/medius, hamstrings, iliopsoas, rectus femoris, vasti, soleus, gastrocnemius.
opensim1-2
Scope of Work
Kicking (SO):
Plot activation(t) & force(t) for the 4 muscles; summarize activation sequence & muscle roles; comment on physiological reasonableness.
opensim1-2
Gait (walk & slow run):
Execute Scale/IK/ID/SO/Muscle Analysis/CMC.
Plot per-muscle forces, moment arms, joint-moment contributions, muscle-tendon power over 0–100% gait.
Compute net joint moments (hip/knee/ankle) and compare vs sum of key muscles’ moments; discuss differences.
Plot neural excitations and make a qualitative EMG comparison; state primary function by phase; identify the most important muscle in stance and swing (walking & running).
Compare SO vs CMC (excitations & forces) and explain differences.
opensim1-2
Muscle grouping rules (must follow):
GMx=glut_max1+2+3; GMe=glut_med1+2+3; Hams=semimem+semiten+bifemlh; Vasti=vas_med+vas_int+vas_lat; Iliopsoas=iliacus+psoas; Gastroc=lat_gas+med_gas.
Do not sum moment arms; sum moments/forces where appropriate.
opensim1-2
Deliverables
Reproducible package: final scaled .osim, setup files for IK/ID/SO/CMC, and resulting .sto/.mot neatly organized by task (kicking/walk/run).
Figures (publication-ready):
Kicking: 4 muscles’ activation(t) & force(t).
Gait (walk & run): per-muscle force / moment arm / joint-moment contribution / muscle-tendon power over 0–100% gait.
Net joint moments vs sum of key muscles’ moments (hip/knee/ankle).
SO vs CMC comparisons (excitations & forces) for representative muscles.
opensim1-2
Short technical note (bullet points OK): activation sequencing & rationale; EMG-style qualitative comparison; net-moment findings; SO vs CMC differences.
Acceptance Criteria / Quality Checks
Pipelines run in OpenSim 4.x without errors; .trc & GRF .mot time axes aligned; filtering choices documented.
Reserve actuators not dominating; results physically plausible.
Clear labels/units/% gait; muscle grouping & “no summing moment arms” strictly followed.
opensim1-2
OpenSim, Biomechanics, Musculoskeletal Modeling, Gait Analysis, Motion Analysis, Static Optimization, Inverse Kinematics, Inverse Dynamics, Computational Modeling, Simulation
Please review the uploaded OpenSim files to understand the task requirements.
If you have experience in similar OpenSim gait or musculoskeletal simulations,
kindly let me know how long you would need to complete this task and how much you would charge,
and include examples or screenshots of your previous related work.